SLCP Research Digest
(August & September 2014)
The SLCP Research Digest is a bi-monthly publication aimed at compiling the top research in fields related to short-lived
climate pollutants. While the Digest draws from a wide list of scientific research publications it is not meant to be a fully
exhaustive compilation of the relevant published research. Suggestions for published research to be included in future
Digests should be emailed to ccac_secretariat@unep.org, with the subject line 'For SLCP Research Digest' we particularly
welcome published research from non-English sources.
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Note - To jump directly to a particular article or section, simply hold ctrl and left click on the title of the article or section
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Table of Contents
Short-Lived Climate Pollutants .................................................................................................................................. 5
Indicators linking health and sustainability in the post-2015 development agenda ................................................................................ 5
Methane .................................................................................................................................................................. 5
Russian policy on methane emissions in the oil and gas sector: A case study in opportunities and challenges in reducing shortlived forcers .............................................................................................................................................................................................. 5
Black Carbon ........................................................................................................................................................... 5
Global and regional climate impacts of black carbon and co-emitted species from the on-road diesel sector ...................................... 6
An approach to a black carbon emission inventory for Mexico by two methods .................................................................................. 6
Atmospheric black carbon deposition and characterization of biomass burning tracers in a northern temperate forest ...................... 6
A size-segregation method for monitoring the diurnal characteristics of atmospheric black carbon size distribution at urban
traffic sites ................................................................................................................................................................................................ 7
Characterization of black carbon at roadside sites and along vehicle roadways in the Bangkok Metropolitan Region ......................... 7
Diesel vehicle and urban burning contributions to black carbon concentrations and size distributions in Tijuana, Mexico,
during the Cal-Mex 2010 campaign ......................................................................................................................................................... 8
Geolocating Russian sources for Arctic black carbon ............................................................................................................................. 8
Black carbon aerosol characterization in a remote area of Qinghai–Tibetan Plateau, western China .................................................... 8
Concentrations, seasonal and diurnal variations of black carbon in PM2.5 in Shanghai, China ............................................................. 9
How shorter black carbon lifetime alters its climate effect ..................................................................................................................... 9
Hydrofluorocarbons & Alternatives ............................................................................................................................ 9
Emissions of halocarbons from mobile vehicle air conditioning system in Hong Kong ....................................................................... 9
Measurements of HFC-134a and HCFC-22 in groundwater and unsaturated-zone air: Implications for HFCs and HCFCs as
dating tracers .......................................................................................................................................................................................... 10
Low GWP alternatives to HFC-245fa in Organic Rankine Cycles for low temperature heat recovery: HCFO-1233zd-E and
HFO-1336mzz-Z ................................................................................................................................................................................... 10
Theoretical comparison of low GWP alternatives for different refrigeration configurations taking R404A as baseline ..................... 11
Assessment of R-438A as a retrofit refrigerant for R-22 in direct expansion water chiller .................................................................. 11
Tropospheric Ozone ................................................................................................................................................ 11
Reductions in India's crop yield due to ozone ....................................................................................................................................... 11
Exhaust emissions of volatile organic compounds of powered two-wheelers: Effect of cold start and vehicle speed.
Contribution to greenhouse effect and tropospheric ozone formation ................................................................................................ 11
Impacts of rising tropospheric ozone on photosynthesis and metabolite levels on field grown soybean ............................................ 12
Current ozone levels threaten gross primary production and yield of Mediterranean annual pastures and nitrogen modulates the
response .................................................................................................................................................................................................. 12
Estimating North American background ozone in U.S. surface air with two independent global models: Variability,
uncertainties, and recommendations ...................................................................................................................................................... 12
Ozone levels in European and USA cities are increasing more than at rural sites, while peak values are decreasing .......................... 13
A study of aerosol optical properties during ozone pollution episodes in 2013 over Shanghai, China ................................................ 13
Ozone — the persistent menace: interactions with the N cycle and climate change ............................................................................ 14
Particulate Matter Air Pollution ................................................................................................................................ 14
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Reassessment of satellite-based estimate of aerosol climate forcing ..................................................................................................... 14
Nature of air pollution, emission sources, and management in the Indian cities .................................................................................. 14
Characteristics of indoor air pollution in rural mountainous and rural coastal communities in Indonesia .......................................... 15
Measuring ambient particulate matter in three cities in Cameroon, Africa ........................................................................................... 15
Assessment of fine and sub-micrometer aerosols at an urban environment of Argentina ................................................................... 15
Indoor air quality in Latino homes in Boulder, Colorado ..................................................................................................................... 16
Air Pollution & Health ............................................................................................................................................. 16
Respiratory risks from household air pollution in low and middle income countries .......................................................................... 16
WHO indoor air quality guidelines on household fuel combustion: Strategy implications of new evidence on interventions and
exposure–risk functions ......................................................................................................................................................................... 17
Cardiovascular and lung function in relation to outdoor and indoor exposure to fine and ultrafine particulate matter in middleaged subjects ........................................................................................................................................................................................... 17
Sources and contents of air pollution affecting term low birth weight in Los Angeles County, California, 2001–2008 ...................... 18
Acute Effects of Particulate Matter and Black Carbon from Seasonal Fires on Peak Expiratory Flow of Schoolchildren in the
Brazilian Amazon ................................................................................................................................................................................... 18
Perinatal and Early Childhood Environmental Factors Influencing Allergic Asthma Immunopathogenesis ...................................... 19
Exposure to Fine Particulate Matter during Pregnancy and Risk of Preterm Birth among Women in New Jersey, Ohio, and
Pennsylvania, 2000–2005 ....................................................................................................................................................................... 19
Particulate Matter Air Pollution Exposure, Distance to Road, and Incident Lung Cancer in the Nurses’ Health Study Cohort ........ 19
Outdoor Particulate Matter Exposure and Lung Cancer: A Systematic Review and Meta-Analysis .................................................... 20
Air Pollution and Respiratory Ailments among Children in Urban India: Exploring Causality ........................................................... 20
Agriculture .............................................................................................................................................................. 21
Organic matter and water management strategies to reduce methane and nitrous oxide emissions from rice paddies in Vietnam .... 21
Measuring methane emissions from two dairy farms: Seasonal and manure-management effects....................................................... 21
Effects of long-term straw incorporation on the net global warming potential and the net economic benefit in a rice–wheat
cropping system in China ....................................................................................................................................................................... 22
Methane and nitrous oxide emissions from flooded rice fields as affected by water and straw management between rice crops ...... 22
Biomass Burning & Cooking and Heating ................................................................................................................ 22
Contrasting long-term records of biomass burning in wet and dry savannas of equatorial East Africa ............................................... 23
Trace gas and particle emissions from open burning of three cereal crop residues: Increase in residue moistness enhances
emissions of carbon monoxide, methane, and particulate organic carbon ............................................................................................ 23
Additional cooking fuel supply and reduced global warming potential from recycling charcoal dust into charcoal briquette in
Kenya...................................................................................................................................................................................................... 23
Indoor–outdoor levels of size segregated particulate matter and mono/polycyclic aromatic hydrocarbons among urban areas
using solid fuels for heating ................................................................................................................................................................... 24
‘Oorja’ in India: Assessing a large-scale commercial distribution of advanced biomass stoves to households .................................... 24
The history, genotoxicity, and carcinogenicity of carbon-based fuels and their emissions. Part 2: Solid fuels..................................... 25
Waste...................................................................................................................................................................... 25
Development of correction factors for landfill gas emission model suiting Indian condition to predict methane emission from
landfills ................................................................................................................................................................................................... 25
Methane production in simulated hybrid bioreactor landfill ................................................................................................................. 25
Extraction of soluble substances from organic solid municipal waste to increase methane production .............................................. 26
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Transport & Industry ............................................................................................................................................... 26
Air pollutant emissions from on-road vehicles in China, 1999–2011 ................................................................................................... 26
Fossil Fuels ............................................................................................................................................................. 26
Methane emissions from natural gas production and use: reconciling bottom-up and top-down measurements ............................... 26
Cross Cutting & Other SLCP Source Sectors.............................................................................................................. 27
Review on greenhouse gas emissions from pig houses: Production of carbon dioxide, methane and nitrous oxide by animals
and manure ............................................................................................................................................................................................. 27
Fuel stacking in India: Changes in the cooking and lighting mix, 1987–2010....................................................................................... 27
Energy poverty reduction by fuel switching. Impact evaluation of the LPG conversion program in Indonesia ................................. 28
Source apportionment of PM2.5 in the harbour–industrial area of Brindisi (Italy): Identification and estimation of the
contribution of in-port ship emissions................................................................................................................................................... 28
Impact of inland shipping emissions on elemental carbon concentrations near waterways in The Netherlands ................................. 28
Aircraft engine exhaust emissions and other airport-related contributions to ambient air pollution: A review ................................... 29
Relating urban airborne particle concentrations to shipping using carbon based elemental emission ratios ....................................... 29
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SHORT-LIVED CLIMATE POLLUTANTS
Indicators linking health and sustainability in the post-2015 development agenda
Abstract - The UN-led discussion about the post-2015 sustainable development agenda provides an opportunity to develop
indicators and targets that show the importance of health as a precondition for and an outcome of policies to promote
sustainable development. Health as a precondition for development has received considerable attention in terms of
achievement of health-related Millennium Development Goals (MDGs), addressing growing challenges of noncommunicable diseases, and ensuring universal health coverage. Much less attention has been devoted to health as an
outcome of sustainable development and to indicators that show both changes in exposure to health-related risks and
progress towards environmental sustainability. We present a rationale and methods for the selection of health-related
indicators to measure progress of post-2015 development goals in non-health sectors. The proposed indicators show the
ancillary benefits to health and health equity (co-benefits) of sustainable development policies, particularly those to reduce
greenhouse gas emissions and increase resilience to environmental change. We use illustrative examples from four thematic
areas: cities, food and agriculture, energy, and water and sanitation. Embedding of a range of health-related indicators in the
post-2015 goals can help to raise awareness of the probable health gains from sustainable development policies, thus making
them more attractive to decision makers and more likely to be implemented than before.
Dora, C., A. Haines, J. Balbus, E. Fletcher, H. Adair-Rohani, G. Alabaster, R. Hossain, M. de Onis, F. Branca, & M. Neira
(2014) Indicators linking health and sustainability in the post-2015 development agenda, The Lancet (early edition).
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METHANE
Russian policy on methane emissions in the oil and gas sector: A case study in opportunities and challenges in
reducing short-lived forcers
Abstract - Methane is a potent greenhouse gas, 21 times as powerful as carbon dioxide in contributing to climate change on
a ton-for-ton basis. Methane, along with other short-lived forcers such as black carbon and tropospheric ozone, could play
an important role in addressing global climate change. This stems both from their overall effect on climate systems, and from
their concentrated impact in the short term. Because reducing emissions of such short-lived pollutants may have a large nearterm impact in slowing climate change, the United States and other countries have come together to cooperate under the
Climate and Clean Air Coalition to Reduce Short-Lived Climate Pollutants, and other partnerships such as the Global
Methane Initiative. For global impact, the success of such partnerships depends on their ability to scale up project-specific
emission reductions.
This paper assesses options and challenges for scaling based on a case study of Russia's oil and gas sector. We examine the
challenges to achieving far-reaching emission reductions, successes of companies to date, how Russia has sought to influence
methane emissions through its environmental fine system, and options for helping companies achieve large-scale emission
reductions in the future through simpler and clearer incentives.
Evans, M., & V. Roshchanka (2014) Russian policy on methane emissions in the oil and gas sector: A case study in opportunities and
challenges in reducing short-lived forcers, ATMOSPHERIC ENVIRONMENT 92:199-20.
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BLACK CARBON
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Global and regional climate impacts of black carbon and co-emitted species from the on-road diesel sector
Abstract - Diesel vehicles are a significant source of black carbon (BC) and ozone precursors, which are important
contributors to climate warming, degrade air quality and harm human health. Reducing diesel emissions could mitigate nearterm climate change with significant co-benefits. This study quantifies the global and regional climate impacts of BC and coemitted short-lived climate forcers (SLCFs) from present-day on-road diesel vehicles, as well as future impacts following a
current legislation emission scenario. Atmospheric concentrations are calculated by the chemical transport model
OsloCTM2. The following radiative forcing (RF) and equilibrium surface temperature responses are estimated. For year 2010
on-road diesel emissions we estimate a global-mean direct RF from BC of 44 m W/m2 and an equilibrium surface
temperature response of 59 mK, including the impact of BC deposition on snow. Accounting for cooling and warming
impacts of co-emitted SLCFs results in a net global-mean RF and warming of 28 mW/m2 and 48 mK, respectively. Using the
concept of Regional Temperature change Potential (RTP), we find significant geographical differences in the responses to
regional emissions. Accounting for the vertical sensitivities of the forcing/response relation amplifies these differences. In
terms of individual source regions, emissions in Europe give the largest regional contribution to equilibrium warming caused
by year 2010 on-road diesel BC, while Russia is most important for Arctic warming per unit emission. The largest
contribution to warming caused by the year 2050 on-road diesel sector is from emissions in South Asia, followed by East
Asia and the Middle East. Hence, in regions where current legislation is not sufficient to outweigh the expected growth in
activity, accelerated policy implementation is important for further future mitigation.
Lund, M. T., T. K. Berntsen, C. Heyes, Z. Klimont, & B. H. Samset (2014) Global and regional climate impacts of black carbon and
co-emitted species from the on-road diesel sector, ATMOSPHERIC ENVIRONMENT 98:50-58.
An approach to a black carbon emission inventory for Mexico by two methods
Abstract - A black carbon (BC) emission inventory for Mexico is presented. Estimate was performed by using two
approaches, based on fuel consumption and emission factors in a top-down scheme, and the second from PM25 emission
data and its correlation with black carbon by source category, assuming that black carbon= elemental carbon. Results show
that black carbon emissions are in interval 53–473 Gg using the fuel consumption approach and between 62 and 89 using
the sector method. Black carbon key sources come from biomass burning in the rural sector, with 47 percent share to the
National total. Mobile sources emissions account to 16% to the total. An opportunity to reduce, in the short-term, carbon
dioxide equivalent (CO2-eq) emissions by reducing black carbon emissions would be obtained in reducing emissions mainly
from biomass burning in rural housing sector and diesel emissions in the transport sector with important co-benefits in
direct radiative forcing, public health and air quality.
Cruz-Nunez, X. (2014) An approach to a black carbon emission inventory for Mexico by two methods, SCIENCE OF THE TOTAL
ENVIRONMENT 479:181-188.
Atmospheric black carbon deposition and characterization of biomass burning tracers in a northern
temperate forest
Abstract - Aerosol black carbon (BC) is considered the second largest contributor to global warming after CO2, and is
known to increase the atmosphere's temperature, decrease the albedo in snow/ice, and influence the properties and
distribution of clouds. BC is thought to have a long mean residence time in soils, and its apparent stability may represent a
significant stable sink for atmospheric CO2. Despite recent efforts to quantify BC in the environment, the quantification of
BC deposition rates from the atmosphere to terrestrial ecosystems remains scarse. To better understand the contribution of
atmospheric BC inputs to soils via dry deposition and its dominant emission sources, atmospheric fine particle (PM 2.5) were
collected at the University of Michigan Biological Station from July to September in 2010 and 2011. PM 2.5 samples were
analyzed for organic C, BC, and molecular markers including particulate sugars, carboxylic acids, n-alkanes, polycyclic
aromatic hydrocarbons, and cholestane. Average atmospheric BC concentrations in northern Michigan were
0.048 ± 0.06 μg m−3 in summer 2010, and 0.049 ± 0.064 μg m−3 in summer 2011. Based on atmospheric concentrations,
particulate deposition calculations, and documented soil BC, we conclude that atmospheric deposition is unlikely to
comprise a significant input pathway for BC in northern forest ecosystem. The major organic tracers identified in fine
particulates (e.g. levoglucosan and docosanoic acid) suggest that ambient PM2.5 concentrations were mainly influenced by
biomass burning and epicuticular plant waxes. These results provide baseline data needed for future assessments of
atmospheric BC in rural temperate forests.
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Santos, F., M. P. Fraser, & J. A. Bird (2014) Atmospheric black carbon deposition and characterization of biomass burning tracers in a
northern temperate forest, ATMOSPHERIC ENVIRONMENT 95:383-390.
A size-segregation method for monitoring the diurnal characteristics of atmospheric black carbon size distribution
at urban traffic sites
Abstract - Understanding the characteristics of the size distribution of ambient black carbon (BC) in distinct environments
is critical because the influence of BC aerosols on climate, visibility, and human health depends strongly on the distribution
of BC aerosols over the particle size spectrum. In this study, a novel method for determining the mass size distribution of
BC in atmospheric aerosols was developed. This size-segregation method relies on measuring BC in parallel using two
aethalometers, one of which is used to measure the total BC (BCT) mass concentration as a reference level and the other is
used to measure the BC (BCi) mass concentration for BC sizes below specific particle sizes that are selected using a size cutoff inlet. In this study, this method was applied to measure BC in atmospheric samples at an urban traffic site. The
aethalometers were operated continually from December 15, 2012 to January 31, 2013, and from February 15, 2013 to
March 31, 2013. The measurement results presented in this paper are for the diurnal variation patterns, average
concentrations, mass fractions, and size distributions of BC aerosols. The results indicate that BC Tmass concentration is
approximately 2.8 μg m−3 in the Taipei urban area. The levels of BC at this sampling site were affected markedly by traffic
emission levels and local wind speed. At the sampling site, the average BC2.5/BCT, BC1.0/BCT, BC0.5/BCT, BC0.25/BCT, and
BC0.1/BCT were 0.96 ± 0.04, 0.92 ± 0.07, 0.89 ± 0.04, 0.73 ± 0.10, and 0.18 ± 0.08, respectively. The results indicate that
approximately 90% of the BC aerosols were smaller than 0.5 μm, that most of the BC aerosols (55%) were in the size range
of 0.1–0.25 μm, and that approximately 18% of the BC aerosols were ultrafine. Moreover, the daily average mass size
distribution of BC exhibited a single accumulation mode at 0.16 μm at this sampling site. The mode of the BC mass size
distribution at rush hour (9 AM) was only 0.14 μm, which is smaller than the daily average. Moreover, the mode of the BC
mass size distribution at an early morning hour (3 AM) was 0.18 μm, and a minor coarse mode was also observed during this
period. The results further revealed that the geometric diameter (Dpg) of the BC aerosols varied between 0.14 and 0.22 μm
and the geometric standard deviation (σg) of these BC aerosols ranged between 1.4 and 2.3 during the sampling period.
Because BC exhibits extremely low chemical reactivity; the size distribution of BC in the atmosphere does not change
substantially except through coagulation.
Cheng, Y.-H., C.-W. Liao, Z.-S. Liu, C.-J. Tsai, & H.-C. His (2014) A size-segregation method for monitoring the diurnal characteristics
of atmospheric black carbon size distribution at urban traffic sites, ATMOSPHERIC ENVIRONMENT 90:78-86.
Characterization of black carbon at roadside sites and along vehicle roadways in the Bangkok Metropolitan
Region
Abstract - To understand the seasonality of concentrations of traffic-related black carbon (BC) in a megacity, BC
concentrations in fine particles were monitored at the roadside and on roads during both the wet and dry seasons of 2010 in
the city center of Bangkok, Thailand. The BC concentration measured every 2 min by an aethalometer at the Dingdaeng
roadside in the dry season was 17.9 ± 6.6 μg m−3, which was 1.6-fold higher than the value (11.5 ± 2.7 μg m−3) during the
wet season. This seasonal difference could not be explained by washout by rain but was instead due to more frequent
upwind conditions caused by a prevailing wind direction from the monitoring site toward the road in the wet season. When
the prevailing wind direction was from the road, the average BC concentration at the roadside increased up to 30 μg m−
3 during both seasons. In contrast, when the wind direction was from the site to the road, the BC concentration was reduced
to the level of urban background concentrations measured inside Lumphini Park and the Dusit Zoo of Bangkok. Roadside
BC concentrations were strongly correlated with NOx concentrations and elemental carbon (EC) concentrations measured in
24-h PM2.5 filter samples. Both relationships exhibited linear determination coefficients of more than 0.80, implying that
NOx can be used as an indicator and an alternative for traffic-related BC at this roadside site when real-time BC monitors are
not available.
The average on-road BC concentration (25.5 μg m−3) was similar to the average at the roadside under downwind conditions
(25.5 μg m−3) from morning to evening only. In contrast, the latter value was 1.7-fold higher than the daily average at the
roadside (14.7 μg m−3) and 7.3-fold higher than the urban background level during the daytime (3.5 μg m−3). The results of
this study suggest that residents who live next to major roads, pedestrians at the roadside, and drivers on the roads
experience a high risk of exposure to severe levels of traffic-related air pollutants.
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Hung, N. T. Q., S. –B. Lee, N. T. Hang, J. Kongpran, N. T. K. Oanh, S.-G. Shim, & G.-N. Bae (2014) Characterization of black
carbon at roadside sites and along vehicle roadways in the Bangkok Metropolitan Region, ATMOSPHERIC ENVIRONMENT 92:231-239.
Diesel vehicle and urban burning contributions to black carbon concentrations and size distributions in Tijuana,
Mexico, during the Cal-Mex 2010 campaign
Abstract - Black carbon (BC) was characterized by three complementary techniques – incandescence (single particle soot
photometer, SP2, at Parque Morelos), light absorption (cavity ringdown spectrometer with integrating nephelometer, CRDSNeph, at Parque Morelos and Aethalometers at seven locations), and volatility (volatility tandem differential mobility
analyzer, V-TDMA) during the Cal-Mex 2010 campaign. SP2, CRDS-Neph, and Aethalometer measurements characterized
the BC mass, and SP2 and V-TDMA measurements also quantified BC-containing particle number, from which mass-mean
BC diameters were calculated. On average, the mass concentrations measured in Tijuana (1.8 ± 2.6 μg m−3 at Parque
Morelos and 2.6 μg m−3 in other regions of Tijuana) were higher than in San Diego or the international border crossing
(0.5 ± 0.6 μg m−3). The observed BC mass concentrations were attributable to nighttime urban burning activities and diesel
vehicles, both from the local (Baja California) and transported (Southern California) diesel vehicle fleets. Comparisons of the
SP2 and co-located Aethalometers indicated that the two methods measured similar variations in BC mass concentrations
(correlation coefficients greater than 0.85), and the mass concentrations were similar for the BC particles identified from
nighttime urban burning sources. When the BC source changed to diesel vehicle emissions, the SP2 mass concentrations
were lower than the Aethalometer mass concentrations by about 50%, likely indicating a change in the mass absorption
efficiency and quantification by the Aethalometers. At Parque Morelos there were up to three different-sized modes of BC
mass in particles: one mode below 100 nm, one near 100 nm, and another between 200 and 300 nm. The mode between 200
and 300 nm was associated with urban burning activities that influenced the site during evening hours. When backtrajectories
indicated that airmasses came from the south to the Parque Morelos site, BC mass in particles was also larger (mass median
diameter of 170 nm rather than 155 nm), consistent with the higher fraction of older diesel vehicles in the Tijuana fleet
compared to the vehicles found in southern California.
Takahama, S., L.M. Russell, C.A. Shores, L.C. Marr, J. Zheng, M. Levy, R. Zhang, E. Castillo, J.G. Rodriguez-Ventura, P.J.E.
Quintana, R. Subramanian, M. Zavala, & L.T. Molina (2014) Diesel vehicle and urban burning contributions to black carbon
concentrations and size distributions in Tijuana, Mexico, during the Cal-Mex 2010 campaign, ATMOSPHERIC ENVIRONMENT 88:341352.
Geolocating Russian sources for Arctic black carbon
Abstract- To design and implement an effective emission control strategy for black carbon (BC), the locations and strength
of BC sources must be identified. Lack of accurate source information from the Russian Federation has created difficulty for
a range of research and policy activities in the Arctic because Russia occupies the largest landmass in the Arctic Circle. A
project was initiated to resolve emission sources of BC in the Russian Federation by using the Potential Source Contribution
Function (PSCF). It used atmospheric BC data from two Arctic sampling stations at Alert Nunavut, Canada, and Tiksi Bay,
Russia. The geographical regions of BC emission sources in Russia were identified and summarized as follows: (1) a region
surrounding Moscow, (2) regions in Eurasia stretching along the Ural Mountains from the White Sea to the Black Sea, and
(3) a number of scattered areas from western Siberia to the Russian Far East. Particulate potassium ions, non-marine sulfate,
and vanadium were used to assist in resolving the source types: forest fire/biomass burning, coal-fired power plant, and oil
combustion. Correlating these maps with the BC map helped to resolve source regions of BC emissions and connect them to
their corresponding source types. The results imply that a region south of Moscow and another north of the Ural Mountains
could be significant BC sources, but none of the grid cells in these regions could be linked to forest fires, oil combustion, or
coal-fired power plants based on these three markers.
Cheng M.-D. (2014) Geolocating Russian sources for Arctic black carbon, ATMOSPHERIC ENVIRONMENT 92:398-410.
Black carbon aerosol characterization in a remote area of Qinghai–Tibetan Plateau, western China
Abstract - The concentrations, size distributions, and mixing states of refractory black carbon (rBC) aerosols were measured
with a ground-based Single Particle Soot Photometer (SP2), and aerosol absorption was measured with an Aethalometer at
Qinghai Lake (QHL), a rural area in the Northeastern Tibetan Plateau of China in October 2011. The area was not pristine,
with an average rBC mass concentration of 0.36 μg STP-m− 3 during the two-week campaign period. The rBC concentration
peaked at night and reached the minimal in the afternoon. This diurnal cycle of concentration is negatively correlated with
the mixed layer depth and ventilation. When air masses from the west of QHL were sampled in late afternoon to early
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evening, the average rBC concentration of 0.21 μg STP-m− 3 was observed, representing the rBC level in a larger Tibetan
Plateau region because of the highest mixed layer depth. A lognormal primary mode with mass median diameter (MMD) of
~ 175 nm, and a small secondary lognormal mode with MMD of 470–500 nm of rBC were observed. Relative reduction in
the secondary mode during a snow event supports recent work that suggested size dependent removal of rBC by
precipitation. About 50% of the observed rBC cores were identified as thickly coated by non-BC material. A comparison of
the Aethalometer and SP2 measurements suggests that non-BC species significantly affect the Aethalometer measurements
in this region. A scaling factor for the Aethalometer data at a wavelength of 880 nm is therefore calculated based on the
measurements, which may be used to correct other Aethalometer datasets collected in this region for a more accurate
estimate of the rBC loading. The results present here significantly improve our understanding of the characteristics of rBC
aerosol in the less studied Tibetan Plateau region and further highlight the size dependent removal of BC via precipitation.
Wang, Q., J.P. Schwarz, J. Cao, R. Gao, D.W. Fahey, T. Hu, R.-J. Huang, Y. Han, & Z. Shen (2014) Black carbon aerosol
characterization in a remote area of Qinghai–Tibetan Plateau, western China, SCIENCE OF THE TOTAL ENVIRONMENT 479–480:151158.
Concentrations, seasonal and diurnal variations of black carbon in PM2.5 in Shanghai, China
Abstract - Concentration of black carbon (BC) in PM2.5 was measured continuously with an aethalometer during January
2010 and December 2011 at an urban site in Shanghai, China. The impact of the emission control measures for the 2010
World Expo and the World Expo event itself on the concentration and temporal variation of BC in Shanghai was discussed.
The annually averaged BC concentrations in 2010 and 2011 in Shanghai were 3.8 ± 2.3 μg m− 3 and 3.3 ± 2.1 μg m− 3
respectively. Higher BC concentrations were found in winter and the lowest monthly concentration occurred in September.
Comparing with the BC concentration in 2011, lower BC concentration was found in spring of 2010 due to the emission
control measures for the Shanghai World Expo and higher BC concentration in summer due to the huge increase of visitors
to the World Expo. Distinct bi-modal diurnal variation of BC was found with the highest evening peak concentration in
Friday and the lowest in Monday. The diurnal variation of BC matched well with the living style of people in Shanghai and
indicated that traffic emission was the main source of BC in urban Shanghai.
Feng, J., M. Zhong, B. Xu, Y. Du, M. Wu, H. Wang, & C. Chen (2014) Concentrations, seasonal and diurnal variations of black
carbon in PM2.5 in Shanghai, China, ATMOSPHERIC RESEARCH 147–148:1-9.
How shorter black carbon lifetime alters its climate effect
Abstract - Black carbon (BC), unlike most aerosol types, absorbs solar radiation. However, the quantification of its climate
impact is uncertain and presently under debate. Recently, attention has been drawn both to a likely underestimation of global
BC emissions in climate models, and an overestimation of BC at high altitudes. Here we show that doubling present day BC
emissions in a model simulation, while reducing BC lifetime based on observational evidence, leaves the direct aerosol effect
of BC virtually unchanged. Increased emissions, together with increased wet removal that reduces the lifetime, yields
modelled BC vertical profiles that are in strongly improved agreement with recent aircraft observations. Furthermore, we
explore the consequences of an altered BC profile in a global circulation model, and show that both the vertical profile of BC
and rapid climate adjustments need to be taken into account in order to assess the total climate impact of BC.
Hodnebrog, O., G. Myhre, & B. H. Samset (2014) How shorter black carbon lifetime alters its climate effect, NATURE
COMMUNICATIONS 5:5065.
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HYDROFLUOROCARBONS & ALTERNATIVES
Emissions of halocarbons from mobile vehicle air conditioning system in Hong Kong
Abstract - During the implementation of Montreal Protocol, emission inventories of halocarbons in different sectors at
regional scale are fundamental to the formulation of relevant management strategy and inspection of the implementation
efficiency. This study investigated the emission profile of halocarbons used in the mobile vehicle air conditioning system, the
leading sector of refrigeration industry in terms of the refrigerant bank, market and emission, in the Hong Kong Special
Administrative Region, using a bottom-up approach developed by 2006 IPCC Good Practice Guidance. The results showed
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that emissions of CFC-12 peaked at 53 tons ODP (Ozone Depletion Potential) in 1992 and then gradually diminished,
whereas HFC-134a presented an increasing emission trend since 1990s and the emissions of HFC-134a reached 65,000 tons
CO2-equivelant (CO2-eq) by the end of 2011. Uncertainty analysis revealed relatively high levels of uncertainties for specialpurpose vehicles and government vehicles. Moreover, greenhouse gas (GHG) abatements under different scenarios indicated
that potential emission reduction of HFC-134a ranged from 4.1 to 8.4 × 105 tons CO2-eq. The findings in this study
advance our knowledge of halocarbon emissions from mobile vehicle air conditioning system in Hong Kong.
Yan, H. H., H. Guo, & J.M. Ou (2014) Emissions of halocarbons from mobile vehicle air conditioning system in Hong Kong, JOURNAL OF
HAZARDOUS MATERIALS 278:401-408.
Measurements of HFC-134a and HCFC-22 in groundwater and unsaturated-zone air: Implications for
HFCs and HCFCs as dating tracers
Abstract - A new analytical method using gas chromatography with an atomic emission detector (GC–AED) was developed
for measurement of ambient concentrations of hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs) in soil,
air, and groundwater, with the goal of determining their utility as groundwater age tracers. The analytical detection limits of
HCFC-22 (difluorochloromethane, CHClF2) and HFC-134a (1,2,2,2-tetrafluoroethane, C2H2F4) in 1 L groundwater
samples are 4.3 × 10− 1 and 2.1 × 10− 1 pmol kg− 1, respectively, corresponding to equilibrium gas-phase mixing ratios of
approximately 5–6 parts per trillion by volume (pptv). Under optimal conditions, post-1960 (HCFC-22) and post-1995
(HFC-134a) recharge could be identified using these tracers in stable, unmixed groundwater samples. Ambient
concentrations of HCFC-22 and HFC-134a were measured in 50 groundwater samples from 27 locations in northern and
western parts of Virginia, Tennessee, and North Carolina (USA), and 3 unsaturated-zone profiles were collected in northern
Virginia. Mixing ratios of both HCFC-22 and HFC-134a decrease with depth in unsaturated-zone gas profiles with an
accompanying increase in CO2 and loss of O2. Apparently, ambient concentrations of HCFC-22 and HFC-134a are readily
consumed by methanotrophic bacteria under aerobic conditions in the unsaturated zone. The results of this study indicate
that soils are a sink for these two greenhouse gases. These observations contradict the previously reported results from
microcosm experiments that found that degradation was limited above-ambient HFC-134a. The groundwater HFC and
HCFC concentrations were compared with concentrations of chlorofluorocarbons (CFCs, CFC-11, CFC-12, CFC-113) and
sulfur hexafluoride (SF6). Nearly all samples had measured HCFC-22 or HFC-134a that were below concentrations
predicted by the CFCs and SF6, with many samples showing a complete loss of HCFC-22 and HFC-134a. This study
indicates that HCFC-22 and HFC-134a are not conservative as environmental tracers and leaves in question the usefulness
of other HCFCs and HFCs as candidate age tracers.
Haase, K. B., E. Busenberg, L. N. Plummer, G. Casile, & W. E. Sanford (2014) Measurements of HFC-134a and HCFC-22 in
groundwater and unsaturated-zone air: Implications for HFCs and HCFCs as dating tracers, CHEMICAL GEOLOGY 385:117-128.
Low GWP alternatives to HFC-245fa in Organic Rankine Cycles for low temperature heat recovery:
HCFO-1233zd-E and HFO-1336mzz-Z
Abstract - HFC-245fa is a common working fluid used in Organic Rankine Cycles generating mechanical power from low
temperature heat. This paper compares the predicted ORC performance of two novel low GWP working fluids, HCFO1233zd-E and HFO-1336mzz-Z, to HFC-245fa over a wide range of evaporating temperatures, condensing temperatures
and vapour superheat values. Expander power output, required pump power input, net cycle efficiencies, mass flow rates and
turbine size parameters with HCFO-1233zd-E, HFO-1336mzz-Z and HFC-245fa were compared for a given thermal power
input. HCFO-1233zd-E and HFO-1336mzz-Z are predicted to have attractive thermodynamic Rankine power cycle
performance. HCFO-1233zd-E would require 10.3%–17.3% lower pump power and would enable up to 10.6% higher net
cycle efficiencies than HFC-245fa over the range of cycle conditions examined in this paper. The turbine size required with
HCFO-1233zd-E would be up to about 7.5%–10.2% larger than with HFC-245fa. HFO-1336mzz-Z would require 36.5%–
41% lower pump power and would enable up to 17% higher net cycle efficiencies than HFC-245fa over the range of cycle
conditions examined in this paper. The turbine size required with HFO-1336mzz-Z would be up to about 30.9%–41.5%
larger than with HFC-245fa. HFO-1336mzz-Z cycle efficiency is benefitted substantially by a recuperator. The net cycle
efficiency increases and the required turbine size decreases relative to HFC-245fa for HCFO-1233zd-E and for HFO1336mzz-Z at higher evaporating and condensing temperatures.
Molés, F., J. Navarro-Esbrí, B. Peris, A. Mota-Babiloni, Á. Barragán-Cervera, & K. Kontomaris (2014) Low GWP alternatives
to HFC-245fa in Organic Rankine Cycles for low temperature heat recovery: HCFO-1233zd-E and HFO-1336mzz-Z, APPLIED
THERMAL ENGINEERING 71(1):204-212.
10
Theoretical comparison of low GWP alternatives for different refrigeration configurations taking R404A as
baseline
Abstract - Six refrigerants are evaluated as low GWP replacements for R404A using different configurations, including twostage system architectures. These refrigerants are selected according to similar characteristics to R404A, and they are the midterm alternatives R407A and R407F, and the long-term alternatives: L40 and DR-7 (with very low GWP and low
flammability), N40 and DR-33 (with low GWP and no flammability). In order to have a complete comparison range, various
operating conditions are considered, covering low and medium evaporator temperatures and two levels of condensation
temperatures. Configurations selected are presented and the equations used to simulate the expected performance are shown.
From a given cooling capacity, volumetric flow rate and COP are compared, taking R404A as baseline. The most efficient
alternatives are the low-flammable refrigerants, L40 and DR-7, and when no flammability is acceptable, N40 and DR-33 are
also very good options.
Mota-Babiloni, A., J. Navarro-Esbrí, Á. Barragán, F. Molés, & B. Peris (2014) Theoretical comparison of low GWP alternatives for
different refrigeration configurations taking R404A as baseline, INTERNATIONAL JOURNAL OF REFRIGERATION 44:81-90.
Assessment of R-438A as a retrofit refrigerant for R-22 in direct expansion water chiller
Abstract - The present work aims to evaluate the performance characteristics of a vapor compression refrigeration system
using R-438A as a retrofit refrigerant for R-22. In order to achieve this objective, a test facility is developed and experiments
are performed over a wide range of chilled water inlet temperature (11:20 °C), condenser water inlet temperature (25:35 °C)
and condenser water mass flow rate (363:543 kg/h). Results showed that as the chilled water inlet temperature changes from
11.5 to 20.5 °C, system COP increases from 1.78 to 2.07 at constant condenser water inlet temperature of 25. 5 °C. Cooling
capacity and COP of the system using R-438A are lower than R-22 by 11% and 12.5%, respectively. However, compressor
discharge temperature using R-438A is slightly lower than R-22 which confirms that R-438A can be used as a retrofit
refrigerant for R-22 to complete the remaining life time of the existing plants.
Elgendy, E., M. Hassanain, & M. Fatouh (2014) Assessment of R-438A as a retrofit refrigerant for R-22 in direct expansion water
chiller, INTERNATIONAL JOURNAL OF REFRIGERATION (In Press).
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TROPOSPHERIC OZONE
Reductions in India's crop yield due to ozone
Abstract - This bottom-up modeling study, supported by emission inventories and crop production, simulates ozone on
local to regional scales. It quantifies, for the first time, potential impact of ozone on district-wise cotton, soybeans, rice, and
wheat crops in India for the first decade of the 21st century. Wheat is the most impacted crop with losses of 3.5 ± 0.8 million
tons (Mt), followed by rice at 2.1 ± 0.8 Mt, with the losses concentrated in central and north India. On the national scale, this
loss is about 9.2% of the cereals required every year (61.2 Mt) under the provision of the recently implemented National
Food Security Bill (in 2013) by the Government of India. The nationally aggregated yield loss is sufficient to feed about 94
million people living below poverty line in India.
Ghude, S. D., C. Jena, D. M. Chate, G. Beig, G. G. Pfister, R. Kumar, & V. Ramanathan (2014) Reductions in India's crop yield
due to ozone, GEOPHYSICAL RESEARCH LETTERS 41(15):5685-5691.
Exhaust emissions of volatile organic compounds of powered two-wheelers: Effect of cold start and
vehicle speed. Contribution to greenhouse effect and tropospheric ozone formation
Abstract - Powered two-wheeler (PTW) vehicles complying with recent European type approval standards (stages Euro 2
and Euro 3) were tested on chassis dynamometer in order to measure exhaust emissions of about 25 volatile organic
compounds (VOCs) in the range C1–C7, including carcinogenic compounds as benzene and 1,3-butadiene. The fleet
consists of a moped (engine capacity ≤ 50 cm3) and three fuel injection motorcycles of different engine capacities (150, 300
and 400 cm3). Different driving conditions were tested (US FPT cycle, constant speed). Due to the poor control of the
combustion and catalyst efficiency, moped is the highest pollutant emitter. In fact, fuel injection strategy and three way
catalyst with lambda sensor are able to reduce VOC motorcycles' emission of about one order of magnitude with respect to
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moped. Cold start effect, that is crucial for the assessment of actual emission of PTWs in urban areas, was significant: 30–
51% of extra emission for methane. In the investigated speed range, moped showed a significant maximum of VOC
emission factor at minimum speed (10 km/h) and a slightly decreasing trend from 20 to 60 km/h; motorcycles showed on
the average a less significant peak at 10 km/h, a minimum at 30–40 km/h and then an increasing trend with a maximum
emission factor at 90 km/h. Carcinogenic VOCs show the same pattern of total VOCs. Ozone Formation Potential (OFP)
was estimated by using Maximum Incremental Reactivity scale. The greatest contribution to tropospheric ozone formation
comes from alkenes group which account for 50–80% to the total OFP. VOC contribution effect on greenhouse effect is
negligible with respect to CO2 emitted.
Costagliola, M. A., F. Murena, & M. V. Prati (2014) Exhaust emissions of volatile organic compounds of powered two-wheelers: Effect of
cold start and vehicle speed. Contribution to greenhouse effect and tropospheric ozone formation, SCIENCE OF THE TOTAL ENVIRONMENT
468–469:1043-1049.
Impacts of rising tropospheric ozone on photosynthesis and metabolite levels on field grown soybean
Abstract - The response of leaf photosynthesis and metabolite profiles to ozone (O3) exposure ranging from 37 to 116 ppb
was investigated in two soybean cultivars Dwight and IA3010 in the field under fully open-air conditions. Leaf
photosynthesis, total non-structural carbohydrates (TNC) and total free amino acids (TAA) decreased linearly with increasing
O3 levels in both cultivars with average decrease of 7% for an increase in O3 levels by 10 ppb. Ozone interacted with
developmental stages and leaf ages, and caused higher damage at later reproductive stages and in older leaves. Ozone
affected yield mainly via reduction of maximum rate of Rubisco carboxylation (Vcmax) and maximum rates of electron
transport (Jmax) as well as a shorter growing season due to earlier onset of canopy senescence. For all parameters
investigated the critical O3 levels (∼50 ppb) for detectable damage fell within O3 levels that occur routinely in soybean fields
across the US and elsewhere in the world. Strong correlations were observed in O3-induced changes among yield,
photosynthesis, TNC, TAA and many metabolites. The broad range of metabolites that showed O3 dose dependent effect is
consistent with multiple interaction loci and thus multiple targets for improving the tolerance of soybean to O3.
Sun, J., Z. Feng, & D. R. Ort (2014) Impacts of rising tropospheric ozone on photosynthesis and metabolite levels on field grown soybean,
PLANT SCIENCE 226:147-161.
Current ozone levels threaten gross primary production and yield of Mediterranean annual pastures and
nitrogen modulates the response
Abstract - Pastures are among the most important ecosystems in Europe considering their biodiversity and distribution area.
However, their response to increasing tropospheric ozone (O3) and nitrogen (N) deposition, two of the main drivers of
global change, is still uncertain. A new Open-Top Chamber (OTC) experiment was performed in central Spain, aiming to
study annual pasture response to O3 and N in close to natural growing conditions. A mixture of six species of three
representative families was sowed in the field. Plants were exposed for 40 days to four O3 treatments: filtered air, nonfiltered air (NFA) reproducing ambient levels and NFA supplemented with 20 and 40 nl l−1 O3. Three N treatments were
considered to reach the N integrated doses of “background”, +20 or +40 kg N ha−1. Ozone significantly reduced green and
total aboveground biomass (maximum reduction 25%) and increased the senescent biomass (maximum increase 40%).
Accordingly, O3 decreased community Gross Primary Production due to both a global reduction of ecosystem CO2
exchange and an increase of ecosystem respiration. Nitrogen could partially counterbalance O3 effects on aboveground
biomass when the levels of O3 were moderate, but at the same time O3 exposure reduced the fertilization effect of higher N
availability. Therefore, O3 must be considered as a stress factor for annual pastures in the Mediterranean areas.
Calvete-Sogo, H., S. Elvira, J. Sanz, I. González-Fernández, H. García-Gómez, L. Sánchez-Martín, R. Alonso, & V. BermejoBermejo (2014) Current ozone levels threaten gross primary production and yield of Mediterranean annual pastures and nitrogen modulates the
response, ATMOSPHERIC ENVIRONMENT 95:197-206.
Estimating North American background ozone in U.S. surface air with two independent global models:
Variability, uncertainties, and recommendations
Abstract - Accurate estimates for North American background (NAB) ozone (O3) in surface air over the United States are
needed for setting and implementing an attainable national O3 standard. These estimates rely on simulations with
atmospheric chemistry-transport models that set North American anthropogenic emissions to zero, and to date have relied
heavily on one global model. We examine NAB estimates for spring and summer 2006 with two independent global models
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(GEOS-Chem and GFDL AM3). We evaluate the base simulations, which include North American anthropogenic
emissions, with mid-tropospheric O3 retrieved from space and ground-level O3 measurements. The models often bracket
the observed values, implying value in developing a multi-model approach to estimate NAB O3. Consistent with earlier
studies, the models robustly simulate the largest nation-wide NAB levels at high-altitude western U.S. sites (seasonal average
maximum daily 8-h values of ∼40–50 ppb in spring and ∼25–40 ppb in summer) where it correlates with observed O3. At
these sites, a 27-year GFDL AM3 simulation simulates observed O3 events above 60 ppb and indicates that year-to-year
variations in NAB O3 influence their annual frequency (with NAB contributing 50–60 ppb or more during individual
events). During summer over the eastern United States (EUS), when photochemical production from regional anthropogenic
emissions peaks, NAB is largely uncorrelated with observed values and it is lower than at high-altitude sites (average values
of ∼20–30 ppb). Four processes contribute substantially to model differences in specific regions and seasons: lightning NOx,
biogenic isoprene emissions and chemistry, wildfires, and stratosphere-to-troposphere transport. Differences in the
representations of these processes within the GFDL AM3 and GEOS-Chem models contribute more to uncertainty in NAB
estimates, particularly in spring when NAB is highest, than the choice of horizontal resolution within a single model (GEOSChem). We propose that future efforts seek to constrain these processes with targeted analysis of multi-model simulations
evaluated with observations of O3 and related species from multiple platforms, and thereby reduce the error on NAB
estimates needed for air quality planning.
Fiore, A.M., J.T. Oberman, M.Y. Lin, L. Zhang, O.E. Clifton, D.J. Jacob, V. Naik, L.W. Horowitz, J.P. Pinto, & G.P. Milly
(2014) Estimating North American background ozone in U.S. surface air with two independent global models: Variability, uncertainties, and
recommendations, ATMOSPHERIC ENVIRONMENT 96:284-300.
Ozone levels in European and USA cities are increasing more than at rural sites, while peak values are
decreasing
Abstract - Ground-level ozone (O3) levels are usually lower in urban centers than nearby rural sites. To compare trends in
O3 levels during the period 1990–2010, we obtained monitoring data from paired urban and rural sites from the European
Environment Agency and the US Environmental Protection Agency. Ozone peaks decreased at both station types, with no
significant differences between urban and rural stations. Ozone annual averages increased at both urban and rural sites, with
a faster rate of increase for urban centers. The overall trend was for convergence between urban and rural O3 data. Ozone
levels exceeded the criteria established for the protection of human and vegetation health at both urban and rural sites.
Paoletti, E., A. De Marco, D.C.S. Beddows, R. M. Harrison, & W. J. Manning (2014) Ozone levels in European and USA cities are
increasing more than at rural sites, while peak values are decreasing, ENVIRONMENTAL POLLUTION 192:295-299.
A study of aerosol optical properties during ozone pollution episodes in 2013 over Shanghai, China
Abstract - Aerosol optical property is essential to the tropospheric ozone formation mechanism while it was rarely measured
in ozone-rich environment for a specific study. With the retrieved products of the sun-photometer, a comparative
investigation was conducted on aerosol optical depth (AOD), single scattering albedo (SSA) and size distribution during
ozone-polluted episodes and clean background. Contrary to expectations, aerosol loading was found positive-correlated with
ozone concentration: daily averaged AOD at 500 nm in ozone episodes (~ 0.78) displayed 2.4 times higher than that in clean
days (~ 0.32). Large Ångström exponent (~ 1.51) along with heavy aerosol loading indicated a considerable impact of fine
particles on optical extinction. The dynamic diurnal fluctuation of these parameters also implied a complex interaction
between aerosols and photo-chemical reactions. The bimodal lognormal distribution pattern for aerosol size spectra
exhibited in both ozone-polluted and clean days. The occurrence of maximum volume concentration (~ 0.28) in fine mode
(radius < 0.6 μm) was observed at 3 p.m. (local time), when ozone was substantially generated. Pronounced scattering feature
of aerosol was reproduced in high-concentration ozone environment. SSA tended to increase continuously from morning (~
0.91 at 440 nm) to afternoon (~ 0.99), which may be associated with secondary aerosol formation. The scattering aerosol
(with moderately high aerosol loading) may favor the ozone formation through increasing solar flux in boundary layer.
Utilizing the micro-pulse lidar (MPL), a more developed planet boundary layer (PBL, top height ~ 1.96 km) was discovered
during ozone-polluted days than clean condition (~ 1.4 km). In episodes, the maximum extinction ratio (~ 0.5 km− 1) was
presented at height of 1.2 km in the late afternoon. The humidity profile by sounding also showed the extreme value at this
altitude. It suggested that optical extinction was mainly attributed to the aerosol in middle PBL, where the intense
photochemical reactions and hydroscopic growth may occur.
Shi, C., S. Wang, R. Liu, R. Zhou, D. Li, W. Wang, Z. Li, T. Cheng, & B. Zhou (2014) A study of aerosol optical properties during
ozone pollution episodes in 2013 over Shanghai, China, ATMOSPHERIC RESEARCH (In Press).
13
Ozone — the persistent menace: interactions with the N cycle and climate change
Abstract - Tropospheric ozone is involved in a complex web of interactions with other atmospheric gases and particles, and
through ecosystem interactions with the N-cycle and climate change. Ozone itself is a greenhouse gas, causing warming, and
reductions in biomass and carbon sequestration caused by ozone provide a further indirect warming effect. Ozone also has
cooling effects, however, for example, through impacts on aerosols and diffuse radiation.
Ecosystems are both a source of ozone precursors (especially of hydrocarbons, but also nitrogen oxides), and a sink through
deposition processes. The interactions with vegetation, atmospheric chemistry and aerosols are complex, and only partially
understood. Levels and patterns of global exposure to ozone may change dramatically over the next 50 years, impacting
global warming, air quality, global food production and ecosystem function.
Simpson, D., A. Arneth, G. Mills, S. Solberg, & J. Uddling (2014) Ozone — the persistent menace: interactions with the N cycle and
climate change, CURRENT OPINION IN ENVIRONMENTAL SUSTAINABILITY 9–10:9-19.
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PARTICULATE MATTER AIR POLLUTION
Reassessment of satellite-based estimate of aerosol climate forcing
Abstract - Large uncertainties exist in estimations of aerosol direct radiative forcing and indirect radiative forcing, and the
values derived from global modeling differ substantially with satellite-based calculations. Following the approach of Quaas et
al. (2008; hereafter named Quaas2008), we reassess satellite-based clear- and cloudy-sky radiative forcings and their seasonal
variations by employing updated satellite products from 2004 to 2011 in combination with the anthropogenic aerosol optical
depth (AOD) fraction obtained from model simulations using the Goddard Earth Observing System-Chemistry-Advanced
Particle Microphysics (GEOS-Chem-APM). Our derived annual mean aerosol clear-sky forcing (−0.59 W m−2) is lower,
while the cloudy-sky forcing (−0.34 W m−2) is higher than the corresponding results (−0.9 W m−2 and −0.2 W m−2,
respectively) reported in Quaas2008. Our study indicates that the derived forcings are sensitive to the anthropogenic AOD
fraction and its spatial distribution but insensitive to the temporal resolution used to obtain the regression coefficients, i.e.,
monthly or seasonal based. The forcing efficiency (i.e., the magnitude per anthropogenic AOD) for the clear-sky forcing
based on this study is 19.9 W m−2, which is about 5% smaller than Quaas2008's value of 21.1 W m−2. In contrast, the
efficiency for the cloudy-sky forcing of this study (11 W m−2) is more than a factor of 2 larger than Quaas2008's value of 4.7
W m−2. Uncertainties tests indicate that anthropogenic fraction of AOD strongly affects the computed forcings while using
aerosol index instead of AOD from satellite data as aerosol proxy does not appear to cause any significant differences in
regression slopes and derived forcings.
Ma, X., F. Yu, & J. Quaas (2014) Reassessment of satellite-based estimate of aerosol climate forcing, JOURNAL OF GEOPHYSICAL
RESEARCH: ATMOSPHERES (early view).
Nature of air pollution, emission sources, and management in the Indian cities
Abstract - The global burden of disease study estimated 695,000 premature deaths in 2010 due to continued exposure to
outdoor particulate matter and ozone pollution for India. By 2030, the expected growth in many of the sectors (industries,
residential, transportation, power generation, and construction) will result in an increase in pollution related health impacts
for most cities. The available information on urban air pollution, their sources, and the potential of various interventions to
control pollution, should help us propose a cleaner path to 2030. In this paper, we present an overview of the emission
sources and control options for better air quality in Indian cities, with a particular focus on interventions like urban public
transportation facilities; travel demand management; emission regulations for power plants; clean technology for brick kilns;
management of road dust; and waste management to control open waste burning. Also included is a broader discussion on
key institutional measures, like public awareness and scientific studies, necessary for building an effective air quality
management plan in Indian cities.
Guttikunda, S. K., R. Goel, P. Pant (2014) Nature of air pollution, emission sources, and management in the Indian cities,
ATMOSPHERIC ENVIRONMENT 95:501-510.
14
Characteristics of indoor air pollution in rural mountainous and rural coastal communities in Indonesia
Abstract - The increased use of biomass fuel use among rural Indonesian households for years despite national program on
subsidized LPG fuel distribution pose threat of indoor air pollution for the householders. Indoor air pollution levels of
PM2.5 and CO in the kitchen of 40 households using the fuelwood as the main cooking fuel were measured in the same
season in mountainous and coastal areas in Indonesia. The temporal variations of PM2.5 and its size distributions were
simultaneously measured using photoelectric UCB monitor and personal cascade impactor, respectively. While carbon
monoxide (CO) concentrations were measured using USB-CO monitors. Household indoor air pollution in the mountainous
area was generally higher than that in the coastal area. This is because the households in coastal area have higher kitchen
volume (about three times), smaller ventilation area (about 1.7 times) and shorter cooking duration with wood fuel (0.6
times) than those in mountainous area. Yet, during cooking with fuelwood, the indoor PM2.5 concentrations at the cook site
showed almost comparable results for both sites. The wood stove burning in coastal area tended to be in flaming
combustion than in mountainous area. This can be indicated by a higher fraction of finest particles in PM2.5, a higher
fraction of EC in PM2.5 and a higher fraction of K+ and Cl− ions in PM2.5 mass concentrations. The time-averaged CO
concentrations for 22-h measurements at the mountainous area were higher than those in coastal area. The mountainous area
showed higher positive correlation relationship between the measured concentrations of CO and PM2.5 than those in the
coastal area. The use of cleaner fuel, e.g., subsidized LPG fuel in rural area should be promoted and managed intensively in
mountainous area than in coastal area to avoid people exposure of health damaging indoor air pollutants.
Huboyo, H. S., S. Tohno, P. Lestari, A. Mizohata, & M. Okumura (2014) Characteristics of indoor air pollution in rural
mountainous and rural coastal communities in Indonesia, ATMOSPHERIC ENVIRONMENT 82:343-350.
Measuring ambient particulate matter in three cities in Cameroon, Africa
Abstract - This is the first study of particulate matter (PM) air pollution in Cameroon. In this study, mass concentration and
PM size fractions as well as carbonaceous contribution to PM are measured in Bafoussam, Bamenda, and Yaoundé,
Cameroon. Average concentrations in Bafoussam, Bamenda, and Yaoundé of PM2.5 are 67 ± 14, 132 ± 64, and 49 ± 12
μg/m3 and PM10 are 105 ± 29, 141 ± 107, and 65 ± 21 μg/m3, respectively. Daytime levels of PM2.5 and PM10 are seen to
be higher than nighttime levels in all cities except Bamenda where nighttime levels are higher for both PM sizes. In
Bafoussam, the average PM1.0 particle number concentration during the day is 19,800 pt/cc and during the evening is
15,200 pt/cc. PM2.5/PM10 mass ratios are 0.65 ± 0.05, 0.75 ± 0.05, and 0.78 ± 0.09 for Bafoussam, Bamenda, and
Yaounde, respectively. Elemental carbon (EC) and organic carbon (OC) contribution to PM2.5 in Bafoussam, Bamenda, and
Yaoundé are 3.9%, 2.9% and 12% for EC and 17.7%, 23.6%, and 34.2% for OC, respectively. After conducting spatial
variability of PM mass concentration and size fractionation sampling at various locations within each of the three cities, we
find that PM2.5 averages are highest during commercial meal preparation in Bafoussam (684 ± 546 μg/m3), and on the road
in Bamenda (417 ± 113 μg/m3) and Yaoundé (110 ± 57 μg/m3). Additional air quality research in Central and West Africa
is necessary to begin implementing policy steps that influence change and to advocate for improved health conditions in this
rapidly expanding region of the world.
Antonel, J., Z. Chowdhury (2014) Measuring ambient particulate matter in three cities in Cameroon, Africa, ATMOSPHERIC
ENVIRONMENT 95:344-354.
Assessment of fine and sub-micrometer aerosols at an urban environment of Argentina
Abstract - Bulk aerosol samples collected during 2010 and 2011 at one receptor site in Córdoba City, Argentina, have been
quantitatively analyzed to determine aerosol elemental composition by using SR-XRF. A receptor model analysis has been
applied to ambient PM2.5 measurements. Four sources have been identified being their contributions: traffic: (13 ± 2) μg
m−3, image/combustion processes, including biomass burning: (15 ± 1) μg m−3, mineral dust: (7 ± 2) μg m−3 and
industry: (8 ± 1) μg m−3. Source identification was carried out by inspection of key species in source profiles, seasonality of
source contributions, comparison with literature data and the knowledge of the city; for the biomass burning contribution
the MODIS burned area daily product was used to confirm wildfire events along the year. In addition, from May to August
2011, aerosols were collected in two additional size fractions (PM0.25–0.5, PM0.5–1) to investigate the toxic metal
contributions to the finer fractions. An important result of this work is that toxic metals make an important contribution to
the finest (PM0.25–0.5) size fraction. The results of the present analysis can help to demonstrate to local and national
authorities the urgent need to carry out emission inventories, to implement air quality monitoring systems and to set
regulations for PM2.5.
15
Achad, M., M. L. López, S. Ceppi, G. G. Palancar, G. Tirao, & B. M. Toselli (2014) Assessment of fine and sub-micrometer aerosols
at an urban environment of Argentina, ATMOSPHERIC ENVIRONMENT 92:522-532.
Indoor air quality in Latino homes in Boulder, Colorado
Abstract - Indoor concentrations of airborne pollutants can be several times higher than those found outdoors, often due to
poor ventilation, overcrowding, and the contribution of indoor sources within a home. Americans spend most of their time
indoors where exposure to poor indoor air quality (IAQ) can result in diminished respiratory and cardiovascular health. This
study measured the indoor air quality in 30 homes of a low-income Latino community in Boulder, Colorado during the
summer of 2012. Participants were administered a survey, which included questions on their health conditions and indoor air
pollution sources like cigarette smoke, heating fuel, and building materials. Twenty-four hour samples of fine particulate
matter (PM2.5) from the indoor air were collected in each home; ambient PM2.5 samples were collected each day as well.
Concurrent air samples were collected onto 47 mm Teflo and Tissuquartz filter at each location. Teflo filters were analyzed
gravimetrically to measure PM2.5 and their extracts were used to determine levels of proteins and endotoxins in the fine
fraction. The Tissuquartz filters were analyzed for elemental and organic carbon content (EC/OC). Results indicated that the
indoor air contained higher concentrations of PM2.5 than the ambient air, and that the levels of OC were much higher than
EC in both indoor and outdoor samples. This community showed no smoking in their homes and kept furry pets indoors at
very low rates; therefore, cooking is likely the primary source of indoor PM. For responders with significant exposure to PM,
it appeared to be primarily from occupational environments or childhood exposure abroad. Our findings indicate that for
immigrant communities such as this, it is important to consider not only their housing conditions but also the relevant prior
exposures when conducting health assessments.
Escobedo, L. E., W. M. Champion, N. Li, & L. D. Montoya (2014) Indoor air quality in Latino homes in Boulder, Colorado,
ATMOSPHERIC ENVIRONMENT 92:69-75.
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AIR POLLUTION & HEALTH
Respiratory risks from household air pollution in low and middle income countries
Abstract - A third of the world's population uses solid fuel derived from plant material (biomass) or coal for cooking,
heating, or lighting. These fuels are smoky, often used in an open fire or simple stove with incomplete combustion, and
result in a large amount of household air pollution when smoke is poorly vented. Air pollution is the biggest environmental
cause of death worldwide, with household air pollution accounting for about 3·5–4 million deaths every year. Women and
children living in severe poverty have the greatest exposures to household air pollution. In this Commission, we review
evidence for the association between household air pollution and respiratory infections, respiratory tract cancers, and chronic
lung diseases. Respiratory infections (comprising both upper and lower respiratory tract infections with viruses, bacteria, and
mycobacteria) have all been associated with exposure to household air pollution. Respiratory tract cancers, including both
nasopharyngeal cancer and lung cancer, are strongly associated with pollution from coal burning and further data are needed
about other solid fuels. Chronic lung diseases, including chronic obstructive pulmonary disease and bronchiectasis in
women, are associated with solid fuel use for cooking, and the damaging effects of exposure to household air pollution in
early life on lung development are yet to be fully described. We also review appropriate ways to measure exposure to
household air pollution, as well as study design issues and potential effective interventions to prevent these disease burdens.
Measurement of household air pollution needs individual, rather than fixed in place, monitoring because exposure varies by
age, gender, location, and household role. Women and children are particularly susceptible to the toxic effects of pollution
and are exposed to the highest concentrations. Interventions should target these high-risk groups and be of sufficient quality
to make the air clean. To make clean energy available to all people is the long-term goal, with an intermediate solution being
to make available energy that is clean enough to have a health impact.
Gordon, S. B., N. G Bruce, J. Grigg, P. L Hibberd, O. P. Kurmi, K. H. Lam, K. Mortimer, K. P. Asante, K. Balakrishnan, J.
Balmes, N. Bar-Zeev, M. N. Bates, P. N. Breysse, S. Buist, Z. Chen, D. Havens, D. Jack, S. Jindal, H. Kan, S. Mehta, P.
Moschovis (2014) Respiratory risks from household air pollution in low and middle income countries, THE LANCET RESPIRATORY
MEDICINE (In Press).
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WHO indoor air quality guidelines on household fuel combustion: Strategy implications of new evidence
on interventions and exposure–risk functions
Abstract - Background: 2.8 billion people use solid fuels as their primary cooking fuel; the resulting high levels of household
air pollution (HAP) were estimated to cause more than 4 million premature deaths in 2012. The people most affected are
among the world's poorest, and past experience has shown that securing adoption and sustained use of effective, lowemission stove technologies and fuels in such populations is not easy. Among the questions raised by these challenges are (i)
to what levels does HAP exposure need to be reduced in order to ensure that substantial health benefits are achieved, and (ii)
what intervention technologies and fuels can achieve the required levels of HAP in practice? New WHO air quality
guidelines are being developed to address these issues. Aims: To address the above questions drawing on evidence from new
evidence reviews conducted for the WHO guidelines. Methods: Discussion of key findings from reviews covering (i)
systematic reviews of health risks from HAP exposure, (ii) newly developed exposure–response functions which combine
combustion pollution risk evidence from ambient air pollution, second-hand smoke, HAP and active smoking, and (iii) a
systematic review of the impacts of solid fuel and clean fuel interventions on kitchen levels of, and personal exposure to,
PM2.5 and carbon monoxide (CO). Findings: Evidence on health risks from HAP suggest that controlling this exposure
could reduce the risk of multiple child and adult health outcomes by 20–50%. The new integrated exposure–response
functions (IERs) indicate that in order to secure these benefits, HAP levels require to be reduced to the WHO IT-1 annual
average level (35 μg/m3 PM2.5), or below. The second review found that, in practice, solid fuel ‘improved stoves’ led to
large percentage and absolute reductions, but post-intervention kitchen levels were still very high, at several hundreds of
μg/m3 of PM2.5, although most solid fuel stove types met the WHO 24-hr average guideline for CO of 7 mg/m3. Clean
fuel user studies were few, but also did not meet IT-1 for PM2.5, likely due to a combination of continuing multiple stove
and fuel use, other sources in the home (e.g. kerosene lamps), and pollution from neighbours and other outdoor sources.
Conclusions: Together, this evidence implies there needs to be a strategic shift towards more rapid and widespread
promotion of clean fuels, along with efforts to encourage more exclusive use and control other sources in and around the
home. For households continuing to rely on solid fuels, the best possible low-emission solid fuel stoves should be promoted,
backed up by testing and in-field evaluation.
Bruce, N., D. Pope, E. Rehfuess, K. Balakrishnan, H. Adair-Rohani, & C. Dora (2014) WHO indoor air quality guidelines on
household fuel combustion: Strategy implications of new evidence on interventions and exposure–risk functions, ATMOSPHERIC
ENVIRONMENT (In Press).
Cardiovascular and lung function in relation to outdoor and indoor exposure to fine and ultrafine
particulate matter in middle-aged subjects
Abstract - This cross-sectional study investigated the relationship between exposure to airborne indoor and outdoor
particulate matter (PM) and cardiovascular and respiratory health in a population-based sample of 58 residences in
Copenhagen, Denmark. Over a 2-day period indoor particle number concentrations (PNC, 10–300 nm) and PM2.5
(aerodynamic diameter < 2.5 μm) were monitored for each of the residences in the living room, and outdoor PNC (10–280
nm), PM2.5 and PM10 (aerodynamic diameter < 10 μm) were monitored at an urban background station in Copenhagen. In
the morning, after the 2-day monitoring period, we measured microvascular function (MVF) and lung function and collected
blood samples for biomarkers related to inflammation, in 78 middle-aged residents. Bacteria, endotoxin and fungi were
analyzed in material from electrostatic dust fall collectors placed in the residences for 4 weeks. Data were analyzed using
linear regression with the generalized estimating equation approach. Statistically significant associations were found between
indoor PNC, dominated by indoor use of candles, and lower lung function, the prediabetic marker HbA1c and systemic
inflammatory markers observed as changes in leukocyte differential count and expression of adhesion markers on
monocytes, whereas C-reactive protein was significantly associated with indoor PM2.5. The presence of indoor endotoxin
was associated with lower lung function and expression of adhesion markers on monocytes. An inverse association between
outdoor PNC and MVF was also statistically significant. The study suggests that PNC in the outdoor environment may be
associated with decreased MVF, while PNC, mainly driven by candle burning, and bioaerosols in the indoor environment
may have a negative effect on lung function and markers of systemic inflammation and diabetes.
Karottki, D. G., G. Bekö, G. Clausen, A. M. Madsen, Z. J. Andersen, A. Massling, M. Ketzel, T. Ellermann, R. Lund, T.
Sigsgaard, P. Møller, & S. Loft (2014) Cardiovascular and lung function in relation to outdoor and indoor exposure to fine and ultrafine
particulate matter in middle-aged subjects, Environment International, Volume 73, December 2014, Pages 372-381.
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Sources and contents of air pollution affecting term low birth weight in Los Angeles County, California,
2001–2008
Background - Low birth weight (LBW, <2500 g) has been associated with exposure to air pollution, but it is still unclear
which sources or components of air pollution might be in play. The association between ultrafine particles and LBW has
never been studied.
Objectives - To study the relationships between LBW in term born infants and exposure to particles by size fraction, source
and chemical composition, and complementary components of air pollution in Los Angeles County (California, USA) over
the period 2001–2008.
Methods - Birth certificates (n=960,945) were geocoded to maternal residence. Primary particulate matter (PM)
concentrations by source and composition were modeled. Measured fine PM, nitrogen dioxide and ozone concentrations
were interpolated using empirical Bayesian kriging. Traffic indices were estimated. Associations between LBW and air
pollution metrics were examined using generalized additive models, adjusting for maternal age, parity, race/ethnicity,
education, neighborhood income, gestational age and infant sex.
Results - Increased LBW risks were associated with the mass of primary fine and ultrafine PM, with several major sources
(especially gasoline, wood burning and commercial meat cooking) of primary PM, and chemical species in primary PM
(elemental and organic carbon, potassium, iron, chromium, nickel, and titanium but not lead or arsenic). Increased LBW
risks were also associated with total fine PM mass, nitrogen dioxide and local traffic indices (especially within 50 m from
home), but not with ozone. Stronger associations were observed in infants born to women with low socioeconomic status,
chronic hypertension, diabetes and a high body mass index.
Conclusions - This study supports previously reported associations between traffic-related pollutants and LBW and suggests
other pollution sources and components, including ultrafine particles, as possible risk factors.
Laurent, O., J. Hu, L. Li, M. Cockburn, L. Escobedo, M. J. Kleeman, & J. Wu (2014) Sources and contents of air pollution affecting
term low birth weight in Los Angeles County, California, 2001–2008, ENVIRONMENTAL RESEARCH (In Press).
Acute Effects of Particulate Matter and Black Carbon from Seasonal Fires on Peak Expiratory Flow of
Schoolchildren in the Brazilian Amazon
Background: Panel studies have shown adverse effects of air pollution from biomass burning on children’s health. This
study estimated the effect of current levels of outdoor air pollution in the Amazonian dry season on peak expiratory flow
(PEF).
Methods: A panel study with 234 schoolchildren from 6 to 15 years old living in the municipality of Tangara´ da Serra, Brazil
was conducted. PEF was measured daily in the dry season in 2008. Mixed-effects models and unified modelling repeated for
every child were applied. Time trends, temperature, humidity, and subject characteristics were regarded. Inhalable particulate
matter (PM10), fine particulate matter (PM2.5), and black carbon (BC) effects were evaluated based on 24-hour exposure
lagged by 1 to 5 days and the averages of 2 or 3 days. Polynomial distributed lag models (PDLM) were also applied.
Results: The analyses revealed reductions in PEF for PM10 and PM2.5 increases of 10 mg/m3 and 1 mg/m3 for BC. For
PM10, the reductions varied from 0.15 (confidence interval (CI)95%: 20.29; 20.01) to 0.25 l/min (CI95%: 20.40; 20.10). For
PM2.5, they ranged from 0.46 (CI95%: 20.86 to 20.06) to 0.54 l/min (CI95%:20.95; 20.14). As for BC, the reduction was
approximately 1.40 l/min. In relation to PDLM, adverse effects were noticed in models based on the exposure on the
current day through the previous 3 days (PDLM 0–3) and on the current day through the previous 5 days (PDLM 0–5),
specially for PM10. For all children, for PDLM 0–5 the global effect was important for PM10, with PEF reduction of 0.31
l/min (CI95%: 20.56; 20.05). Also, reductions in lags 3 and 4 were observed. These associations were stronger for children
between 6 and 8 years old.
Conclusion: Reductions in PEF were associated with air pollution, mainly for lagged exposures of 3 to 5 days and for
younger children.
Jacobson, L. S. V., S. S. Hacon, H. A. de Castro, E. Ignotti, P. Artaxo, P. H. N. Saldiva, & A. C. M. Ponce de Leon (2014)
Acute Effects of Particulate Matter and Black Carbon from Seasonal Fires on Peak Expiratory Flow of Schoolchildren in the Brazilian
Amazon, PLOS ONE 9(8).
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Perinatal and Early Childhood Environmental Factors Influencing Allergic Asthma Immunopathogenesis
Background - The prevalence of asthma has increased dramatically over the past several decades. While hereditary factors
are highly important, the rapid rise outstrips the pace of genomic variation. Great emphasis has been placed on potential
modifiable early life exposures leading to childhood asthma.
Methods - We reviewed the recent medical literature for important studies discussing the role of the perinatal and early
childhood exposures and the inception of childhood asthma.
Results and Discussion - Early life exposure to allergens (House dust mite (HDM), furred pets, cockroach, rodent and
mold)air pollution (nitrogen dioxide (NO2), ozone (O3), volatile organic compounds (VOCs), and particulate matter (PM))
and viral respiratory tract infections (Respiratory syncytial virus (RSV) and human rhinovirus (hRV)) have been implicated in
the development of asthma in high risk children. Conversely, exposure to microbial diversity in the perinatal period may
diminish the development of atopy and asthma symptoms.
Gaffin, J. M., W. Kanchongkittiphon, & Wanda Phipatanakul (2014) Perinatal and Early Childhood Environmental Factors
Influencing Allergic Asthma Immunopathogenesis, INT IMMUNOPHARMACOL. 22(1):21-30.
Exposure to Fine Particulate Matter during Pregnancy and Risk of Preterm Birth among Women in New
Jersey, Ohio, and Pennsylvania, 2000–2005
Background: Particulate matter ≤ 2.5 μm in aerodynamic diameter (PM2.5) has been variably associated with preterm birth
(PTB).
Objective: We classified PTB into four categories (20–27, 28–31, 32–34, and 35–36 weeks completed gestation) and
estimated risk differences (RDs) for each category in association with a 1-μg/m3 increase in PM2.5 exposure during each
week of gestation.
Methods: We assembled a cohort of singleton pregnancies that completed ≥ 20 weeks of gestation during 2000–2005 using
live birth certificate data from three states (Pennsylvania, Ohio, and New Jersey) (n = 1,940,213; 8% PTB). We estimated
mean PM2.5 exposures for each week of gestation from monitor-corrected Community Multi-Scale Air Quality modeling
data. RDs were estimated using modified Poisson linear regression and adjusted for maternal race/ethnicity, marital status,
education, age, and ozone.
Results: RD estimates varied by exposure window and outcome period. Average PM2.5 exposure during the fourth week of
gestation was positively associated with all PTB outcomes, although magnitude varied by PTB category [e.g., for a 1-μg/m3
increase, RD = 11.8 (95% CI: –6, 29.2); RD = 46 (95% CI: 23.2, 68.9); RD = 61.1 (95% CI: 22.6, 99.7); and RD = 28.5 (95%
CI: –39, 95.7) for preterm births during 20–27, 28–31, 32–34, and 35–36 weeks, respectively]. Exposures during the week of
birth and the 2 weeks before birth also were positively associated with all PTB categories.
Conclusions: Exposures beginning around the time of implantation and near birth appeared to be more strongly associated
with PTB than exposures during other time periods. Because particulate matter exposure is ubiquitous, evidence of effects of
PM2.5 exposure on PTB, even if small in magnitude, is cause for concern.
Rappazzo, K. M., J. L. Daniels, L. C. Messer, C. Poole, & D. T. Lobdell (2014) Exposure to Fine Particulate Matter during
Pregnancy and Risk of Preterm Birth among Women in New Jersey, Ohio, and Pennsylvania, 2000–2005, ENVIRON HEALTH PERSPECT.
122(9):992-997.
Particulate Matter Air Pollution Exposure, Distance to Road, and Incident Lung Cancer in the Nurses’
Health Study Cohort
Background: A body of literature has suggested an elevated risk of lung cancer associated with particulate matter and
traffic-related pollutants.
Objective: We examined the relation of lung cancer incidence with long-term residential exposures to ambient particulate
matter and residential distance to roadway, as a proxy for traffic-related exposures.
Methods: For participants in the Nurses’ Health Study, a nationwide prospective cohort of women, we estimated 72-month
average exposures to PM2.5, PM2.5–10, and PM10 and residential distance to road. Follow-up for incident cases of lung
19
cancer occurred from 1994 through 2010. Cox proportional hazards models were adjusted for potential confounders. Effect
modification by smoking status was examined.
Results: During 1,510,027 person-years, 2,155 incident cases of lung cancer were observed among 103,650 participants. In
fully adjusted models, a 10-μg/m3 increase in 72-month average PM10 [hazard ratio (HR) = 1.04; 95% CI: 0.95, 1.14],
PM2.5 (HR = 1.06; 95% CI: 0.91, 1.25), or PM2.5–10 (HR = 1.05; 95% CI: 0.92, 1.20) was positively associated with lung
cancer. When the cohort was restricted to never-smokers and to former smokers who had quit at least 10 years before, the
associations appeared to increase and were strongest for PM2.5 (PM10: HR = 1.15; 95% CI: 1.00, 1.32; PM2.5: HR = 1.37;
95% CI: 1.06, 1.77; PM2.5–10: HR = 1.11; 95% CI: 0.90, 1.37). Results were most elevated when restricted to the most
prevalent subtype, adenocarcinomas. Risks with roadway proximity were less consistent.
Conclusions: Our findings support those from other studies indicating increased risk of incident lung cancer associated with
ambient PM exposures, especially among never- and long-term former smokers.
Puett, R. C., J. E. Hart, J. D. Yanosky, D. Spiegelman, M. Wang, J. A. Fisher, B. Hong, & F. Laden (2014) Particulate Matter
Air Pollution Exposure, Distance to Road, and Incident Lung Cancer in the Nurses’ Health Study Cohort, ENVIRON HEALTH PERSPECT.
122(9):926–932.
Outdoor Particulate Matter Exposure and Lung Cancer: A Systematic Review and Meta-Analysis
Background: Particulate matter (PM) in outdoor air pollution was recently designated a Group I carcinogen by the
International Agency for Research on Cancer (IARC). This determination was based on the evidence regarding the
relationship of PM2.5 and PM10 to lung cancer risk; however, the IARC evaluation did not include a quantitative summary
of the evidence.
Objective: Our goal was to provide a systematic review and quantitative summary of the evidence regarding the relationship
between PM and lung cancer.
Methods: We conducted meta-analyses of studies examining the relationship of exposure to PM2.5 and PM10 with lung
cancer incidence and mortality. In total, 18 studies met our inclusion criteria and provided the information necessary to
estimate the change in lung cancer risk per 10-μg/m3 increase in exposure to PM. We used random-effects analyses to allow
between-study variability to contribute to meta-estimates.
Results: The meta-relative risk for lung cancer associated with PM2.5 was 1.09 (95% CI: 1.04, 1.14). The meta-relative risk of
lung cancer associated with PM10 was similar, but less precise: 1.08 (95% CI: 1.00, 1.17). Estimates were robust to restriction
to studies that considered potential confounders, as well as subanalyses by exposure assessment method. Analyses by
smoking status showed that lung cancer risk associated with PM2.5 was greatest for former smokers [1.44 (95% CI: 1.04,
1.22)], followed by never-smokers [1.18 (95% CI: 1.00, 1.39)], and then current smokers [1.06 (95% CI: 0.97, 1.15)]. In
addition, meta-estimates for adenocarcinoma associated with PM2.5 and PM10 were 1.40 (95% CI: 1.07, 1.83) and 1.29 (95%
CI: 1.02, 1.63), respectively.
Conclusion: The results of these analyses, and the decision of the IARC Working Group to classify PM and outdoor air
pollution as carcinogenic (Group 1), further justify efforts to reduce exposures to air pollutants that can arise from many
sources.
Hamra, G. B., N. Guha, A. Cohen, F. Laden, O. Raaschou-Nielsen, J. M. Samet, P. Vineis, F. Forastiere, P. Saldiva, T.
Yorifuji, & D. Loomis (2014) Outdoor Particulate Matter Exposure and Lung Cancer: A Systematic Review and Meta-Analysis,
ENVIRON HEALTH PERSPECT. 122(9):906–911.
Air Pollution and Respiratory Ailments among Children in Urban India: Exploring Causality
Abstract - Economic growth and increasing urbanization of emerging economies such as India’s have been accompanied by
a rise in ambient air pollution levels, especially in urban areas.1 However, the causal relationship between ambient air
pollution and child health, although important in the context of such economywide changes, has remained relatively
understudied. Examining the effects of air quality on health in developing countries has proved to be especially challenging
due to the high cost of directly measuring pollution and the limited infrastructure for undertaking such measurements on a
continuous and comprehensive basis. Among the few studies that are available, several have been constrained to look at
specific regions or cities and rely on small sample sizes ðLahiri et al. 2000; Jayaraman and Nidhi 2008; Atkinson et al. 2012Þ.
With rising levels of urban air pollution, studies focusing on the relationship between ambient air quality and health are now
increasingly relevant for developing countries.
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Ghosh, A., & A. Mukherji (2014) Air Pollution and Respiratory Ailments among Children in Urban India: Exploring Causality,
ECONOMIC DEVELOPMENT AND CULTURAL CHANGE 63(1):191-222.
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AGRICULTURE
Organic matter and water management strategies to reduce methane and nitrous oxide emissions from
rice paddies in Vietnam
Abstract - The reduction of CH4 and N2O emissions from rice paddies is of utmost importance in minimizing the impact of
rice production on global warming. A field experiment was therefore conducted in farmers' field in Hanoi, Vietnam to
examine whether the use of straw compost or straw biochar, in combination with the safe alternate wetting and drying
(AWD) has the potential to suppress both CH4 and N2O emissions from rice paddies while maintaining the rice yield. The
study compared the proposed strategies with local farmers' practice of permanent flooding (PF) and farmyard manure (FYM)
incorporation, respectively. A control treatment without organic matter incorporation in both AWD and PF water regimes
was also included in the study; all treatments received equal amounts of mineral fertilizer. Gas emissions were monitored
using the closed chamber method at seven-day intervals during the first 50 days and at 15-day intervals thereafter. Addition
of FYM, straw compost and biochar increased CH4 emissions by 230%, 150% and 38%, respectively, when compared with
the control treatments in both the AWD and PF water regimes. Within AWD, FYM increased N2O emissions by 30%, straw
compost and biochar displayed similar amount of N2O emissions as the control treatment. Within PF, N2O emissions under
FYM and straw compost were 40% and 35% higher than the control treatment, respectively, and biochar once again
displayed similar amount of N2O emissions as the control treatment. Yield difference was not significant (p > 0.05) between
any of the treatments. These results indicated that the straw compost incorporation might not reduce the global warming
potential (GWP) and yield-scaled GWP of rice production, whereas biochar in combination with AWD has the potential to
maintain the GWP and yield-scaled GWP of rice production at lower level than the farmers' practice.
Pandey, A., V. T. Mai, D. Q. Vu, T. P. L. Bui, T. L. A. Mai, L. S. Jensen, & A. de Neergaard (2014) Organic matter and water
management strategies to reduce methane and nitrous oxide emissions from rice paddies in Vietnam, AGRICULTURE, ECOSYSTEMS &
ENVIRONMENT 196:137-146.
Measuring methane emissions from two dairy farms: Seasonal and manure-management effects
Abstract - There is a need to improve the understanding of methane (CH4) emissions on multiple spatial and temporal
scales, and on a sector basis. Livestock are significant contributors to the CH4 budget, with emissions coming from enteric
fermentation by ruminants and management of liquid manure. Inventory estimates for methane emissions are based on
methodology that needs to be verified with actual on-farm measurements. Responding to these needs, the objectives of this
study were to apply the backward Lagrangian Stochastic (bLS) technique on small dairy farms (50-100 lactating cows) and to
examine its suitability to determine CH4 emissions from whole farms and partition emissions from cattle and manure.
Measurement campaigns were selected to characterize the emission response to farm management activities and seasonal
changes. At both farms the whole-farm emission rate was measured when the liquid manure storages were either full or
emptied. Emissions from manure were substantial, and in the fall when the manure storage was full, 60% of the whole farm
emissions came from the manure storage. Substantial seasonal differences in whole-farm emissions were observed, with fall
season emissions being ∼40% higher than in the spring due to much higher manure emissions in the fall (673 g lactatingcow−1 d−1) than the spring (249 g lactating-cow−1 d−1). Peak emissions from stored manure were 47 kg CH4 h−1, (730 g
lactating-cow−1 h−1) during agitation. The enteric emission rate from the animals (after subtracting estimated barn floor
emissions) showed clear diurnal variation and on a daily basis was similar for both seasons, ranging between 270 and 380 g
lactating cow−1 d−1. Implied Ym values were lower than the IPCC default value. Methane emissions from manure
exhibited pronounced temporal variation on multiple time-frames and as a result, more research is needed to fully describe
annual CH4 emissions from liquid manure management.
VanderZaag, A.C., T.K. Flesch, R.L. Desjardins, H. Baldé, & T. Wright (2014) Measuring methane emissions from two dairy farms:
Seasonal and manure-management effects, AGRICULTURAL AND FOREST METEOROLOGY 194:259-267.
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Effects of long-term straw incorporation on the net global warming potential and the net economic benefit
in a rice–wheat cropping system in China
Abstract - Straw incorporation has multiple effects on greenhouse gas emissions and soil productivity. However, few studies
have comprehensively evaluated the effects of long-term straw incorporation. An ongoing long-term straw incorporation
experiment in a rice–wheat cropping system in China was established in 1990 and was used in the present study to evaluate
the net global warming potential (NGWP) and the net economic benefit (NEB) of the straw return. The following four field
treatments were included: a control (CK); N, P and K fertilization (NPK); fertilization plus a moderate rate of straw
application (NPKS1); and fertilization plus a high rate of straw application (NPKS2). We calculated the increase in the soil
organic carbon (SOC) and the straw-induced emissions of CH4 and N2O, which were expressed as the global warming
potential (GWP) in units of CO2-equivalent (CO2-eq) at the 100-year scale. The straw-induced NEB was defined as the
difference between the economic income, which was calculated by multiplying the increase in straw-induced crop grain yield
by the grain price, and the economic loss was computed by multiplying the increase in straw-induced CO2-eq emissions by
the carbon price. The results showed that long-term straw incorporation significantly increased the CH4 emissions and the
topsoil SOC density. The GWP of the straw-induced CH4 emissions was 3.21–3.92 times that of the straw-induced SOC
sequestration rate, suggesting that long-term direct straw incorporation in the rice–wheat systems worsens rather than
mitigates the climate change. Additionally, continuous straw incorporation slightly enhanced the rice and wheat grain yields,
contributing to the production of the NEB. We determined that under the current carbon price, ranging from 2.55 to 31.71
EUR per ton CO2-eq, the direct straw incorporation will produce a positive NEB, ranging from 156 to 658 RMB ha−1
year−1, if the grain yield prices do not fluctuate, which does not provide a significant incentive for farmers to change from
their traditional direct straw incorporation pattern. Considering the other benefits that the straw application produced, such
as improving soil fertility and the water retention capacity, we recommend that the government should establish an incentive
for ecological compensation to encourage farmers to implement proper straw incorporation, such as composting straw
under aerobic conditions before application.
Xia, L., S. Wang, & X. Yan (2014) Effects of long-term straw incorporation on the net global warming potential and the net economic benefit in
a rice–wheat cropping system in China, AGRICULTURE, ECOSYSTEMS & ENVIRONMENT 197:118-127.
Methane and nitrous oxide emissions from flooded rice fields as affected by water and straw management
between rice crops
Abstract - Rice fields in the tropics can vary in water regime before production of rice on flooded soil, but relatively little is
known about the effects of soil water regime and crop residue management between rice crops (i.e., fallow period) on
methane (CH4) and nitrous oxide (N2O) emissions during a subsequent rice crop. We measured CH4 and N2O emissions
during two cropping seasons in the Philippines from field plots exposed to contrasting treatments during the fallow before
land preparation for rice cultivation. The fallow treatments were continuous soil flooding (flooded), soil drying with
exclusion of rainfall (dry), soil drying with dry tillage (dry + tillage), and a control with soil drying and wetting from rainfall
(dry and wet). All plots were subdivided into removal of all aboveground rice residues from the previous crop (without
residue) and retention of standing biomass after harvest of the previous rice crop (with residue). Emitted gas was collected
weekly using chambers. Fallow treatments greatly influenced greenhouse gas (GHG) emissions during rice growth. Methane
emissions and global warming potential (GWP) in both cropping seasons were highest following the flooded fallow,
intermediate following the dry and wet fallow, and lowest following dry and dry + tillage fallows. The GWP was higher with
than without residue across all fallow treatments. Nitrous oxide emissions were small during the season, and CH4 emissions
contributed more than 90% of the cumulative GWP during the rice crop regardless of fallow and residue management. Soil
drying between rice crops in the tropics can reduce CH4 emissions and GWP during the subsequent rice crop.
Sander, B. O., M. Samson, & R. J. Buresh (2014) Methane and nitrous oxide emissions from flooded rice fields as affected by water and
straw management between rice crops, GEODERMA 235–236:355-362.
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BIOMASS BURNING & COOKING AND HEATING
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Contrasting long-term records of biomass burning in wet and dry savannas of equatorial East Africa
Abstract - Rainfall controls fire in tropical savanna ecosystems through impacting both the amount and flammability of
plant biomass, and consequently, predicted changes in tropical precipitation over the next century are likely to have
contrasting effects on the fire regimes of wet and dry savannas. We reconstructed the long-term dynamics of biomass
burning in equatorial East Africa, using fossil charcoal particles from two well-dated lake-sediment records in western
Uganda and central Kenya. We compared these high-resolution (5 years/sample) time series of biomass burning, spanning
the last 3800 and 1200 years, with independent data on past hydroclimatic variability and vegetation dynamics. In western
Uganda, a rapid (<100 years) and permanent increase in burning occurred around 2170 years ago, when climatic drying
replaced semideciduous forest by wooded grassland. At the century time scale, biomass burning was inversely related to
moisture balance for much of the next two millennia until ca. 1750 AD, when burning increased strongly despite regional
climate becoming wetter. A sustained decrease in burning since the mid20th century reflects the intensified modern-day
landscape conversion into cropland and plantations. In contrast, in semiarid central Kenya, biomass burning peaked at
intermediate moisture-balance levels, whereas it was lower both during the wettest and driest multidecadal periods of the last
1200 years. Here, burning steadily increased since the mid20th century, presumably due to more frequent deliberate ignitions
for bush clearing and cattle ranching. Both the observed historical trends and regional contrasts in biomass burning are
consistent with spatial variability in fire regimes across the African savanna biome today. They demonstrate the strong
dependence of East African fire regimes on both climatic moisture balance and vegetation, and the extent to which this
dependence is now being overridden by anthropogenic activity.
Colombaroli, D., I. Ssemmanda, Vanessa Gelorini, & D. Verschuren (2014) Contrasting long-term records of biomass burning in wet
and dry savannas of equatorial East Africa, GLOBAL CHANGE BIOLOGY 20(9):2903-2914.
Trace gas and particle emissions from open burning of three cereal crop residues: Increase in residue moistness
enhances emissions of carbon monoxide, methane, and particulate organic carbon
Abstract - We determined emission factors for open burning of straw of rice, wheat, and barley, as well as rice husks, and
we incorporated the effects of moisture content on the emission factors for the straw. A closed system that simulated on-site
backfiring of residues on the soil surface under moderate wind conditions was used to measure the gas and particle emissions
from open burning of the residues on an upland field. Two moisture content conditions were evaluated: a dry condition (airdried residues, 11–13% by weight) and a moist condition (20%). When a linear regression model with the initial moisture
content of the residue as the explanatory variable showed good correlation between the primary emission data of a substance
and the moisture content, the regression model was adopted as a function to give the emission factors. Otherwise, the
unmodified primary data were used as the emission factors. The magnitudes of the gas and particle emissions differed among
the residue types. For example, carbon monoxide (CO) emissions from straw of rice, wheat, and barley and rice husks
burned under the dry condition were 27.2 ± 1.7, 41.8 ± 24.2, 46.9 ± 2.1, and 66.1 g kg−1 dry matter, and emissions of
methane (CH4) were 0.75 ± 0.01, 2.01 ± 0.93, 1.47 ± 0.06, and 5.81 g kg−1 dry matter, respectively (n = 2 for straw with
the standard deviation;n = 1 for husks). Emissions of carbon-containing gases and particles (e.g., CO, CH4, and particulate
organic carbon) were higher under the moist condition than under the dry condition, which suggests that emission factors
for open burning should incorporate the effects of moisture content except open burning performed in the dry season or
arid zones.
Hayashi, K., K. Ono, M. Kajiura, S. Sudo, S. Yonemura, A. Fushimi, K. Saitoh, Y. Fujitani, & K. Tanabe (2014) Trace gas and
particle emissions from open burning of three cereal crop residues: Increase in residue moistness enhances emissions of carbon monoxide, methane,
and particulate organic carbon, ATMOSPHERIC ENVIRONMENT 95:36-44.
Additional cooking fuel supply and reduced global warming potential from recycling charcoal dust into
charcoal briquette in Kenya
Abstract - Rising demand for energy is one of the major challenges facing the world today and charcoal is a principal fuel in
Kenya. Faced with energy poverty many poor households turn to briquette making. This study assessed the additional
cooking fuel obtained from recycling charcoal dust into charcoal briquettes. It applied Life Cycle Assessment (LCA) to assess
the global warming potential (GWP) from use of charcoal and production of briquettes from charcoal dust and cooking a
traditional meal for a standard household of five people. Native vegetation of Acacia drepanolobium and a low efficiency
kiln were considered the common practice, while an Acacia mearnsii plantation and a high efficiency kiln was used as an
alternative scenario. Charcoal and kerosene were considered as reference fuels. Recovering charcoal dust for charcoal
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briquettes supplied an additional 16% cooking fuel. Wood carbonization and cooking caused the highest GWP, so there is a
need for technologies to improve the efficiency at these two stages of charcoal briquettes and charcoal supply chain.
Supplying energy and cooking a traditional meal in a combined system using charcoal and recovering charcoal dust for
charcoal briquettes and charcoal alone accounted for 5.3–4.12 and 6.4–4.94 kg CO2 eq. per meal, respectively, assuming
trees were not replanted. These amounts declined three times when the carbon dioxide from the carbonization and cooking
stages was assumed to be taken up by growing biomass. This requires replanting of trees cut down for charcoal if the neutral
impact of biomass energy on GWP is to be maintained.
Njenga, M., N. Karanja, H. Karlsson, R. Jamnadass, M. Iiyama, J. Kithinji, & C. Sundberg (2014) Additional cooking fuel supply
and reduced global warming potential from recycling charcoal dust into charcoal briquette in Kenya, JOURNAL OF CLEANER PRODUCTION
81:81-88.
Indoor–outdoor levels of size segregated particulate matter and mono/polycyclic aromatic hydrocarbons
among urban areas using solid fuels for heating
Abstract - Emissions from the fuel combustion in the energy production are causes of concern due to associated health
risks, but little information is available on the impact of residential fuel burning on indoor air quality, where most of the
human exposure occurs. In this complex study, concentrations of size-segregated particulate matter (PM), monocyclic and
polycyclic aromatic compounds (MAHs and PAHs) at indoor and outdoor sites in six urban homes in the city of Kaunas,
Lithuania, were determined over winter and summer sampling campaigns, specifically targeting the impact of the local fuel
burning to the indoor air quality. PM levels observed in Kaunas during winter measurement campaign were higher compared
to those in many other European settlements utilizing biomass for energy production. The particle size distribution analysis
revealed that the major part of the PM mass in winter period consisted of fine particles (PM2.5). Both MAH and PAH levels
were higher in winter. The indoor to outdoor ratios (I/O) of MAHs and PAHs revealed specific patterns depending on the
presence of emissions sources indoors. Irrespectively of the season, I/O values were <1, suggesting that in case of the
absence of an indoor pollution, the dominant source of organic compounds was from the outdoor environment. In homes
with no PAH source inside, the I/O ratio equalled ranged from 0.05 to 0.36, suggesting the penetrated portion of outdoor
combustion particles to the indoor air.
Kliucininkas, L., E. Krugly, I. Stasiulaitiene, I. Radziuniene, T. Prasauskas, A. Jonusas, V. Kauneliene, & D. Martuzevicius
(2014) Indoor–outdoor levels of size segregated particulate matter and mono/polycyclic aromatic hydrocarbons among urban areas using solid fuels
for heating, ATMOSPHERIC ENVIRONMENT 97:83-93.
‘Oorja’ in India: Assessing a large-scale commercial distribution of advanced biomass stoves to
households
Abstract - Replacing traditional stoves with advanced alternatives that burn more cleanly has the potential to ameliorate
major health problems associated with indoor air pollution in developing countries. With a few exceptions, large government
and charitable programs to distribute advanced stoves have not had the desired impact. Commercially-based distributions
that seek cost recovery and even profits might plausibly do better, both because they encourage distributors to supply and
promote products that people want and because they are based around properly-incentivized supply chains that could more
be scalable, sustainable, and replicable.
The sale in India of over 400,000 “Oorja” stoves to households from 2006 onwards represents the largest commerciallybased distribution of a gasification-type advanced biomass stove. BP's Emerging Consumer Markets (ECM) division and
then successor company First Energy sold this stove and the pelletized biomass fuel on which it operates. We assess the
success of this effort and the role its commercial aspect played in outcomes using a survey of 998 households in areas of
Maharashtra and Karnataka where the stove was sold as well as detailed interviews with BP and First Energy staff. Statistical
models based on this data indicate that Oorja purchase rates were significantly influenced by the intensity of Oorja marketing
in a region as well as by pre-existing stove mix among households. The highest rate of adoption came from LPG-using
households for which Oorja's pelletized biomass fuel reduced costs. Smoke- and health-related messages from Oorja
marketing did not significantly influence the purchase decision, although they did appear to affect household perceptions
about smoke. By the time of our survey, only 9% of households that purchased Oorja were still using the stove, the result in
large part of difficulties First Energy encountered in developing a viable supply chain around low-cost procurement of
“agricultural waste” to make pellets. The business orientation of First Energy allowed the company to pivot rapidly to
commercial customers when the household market encountered difficulties. The business background of managers also
facilitated the initial marketing and distribution efforts that allowed the stove distribution to reach scale.
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Thurber, M. C., H. Phadke, S. Nagavarapu, G. Shrimali, & H. Zerriffi (2014) ‘Oorja’ in India: Assessing a large-scale commercial
distribution of advanced biomass stoves to households, ENERGY FOR SUSTAINABLE DEVELOPMENT 19:138-150.
The history, genotoxicity, and carcinogenicity of carbon-based fuels and their emissions. Part 2: Solid
fuels
Abstract - The combustion of solid fuels (like wood, animal dung, and coal) usually involves elevated temperatures and
altered pressures and genotoxicants (e.g., PAHs) are likely to form. These substances are carcinogenic in experimental
animals, and epidemiological studies implicate these fuels (especially their emissions) as carcinogens in man. Globally, ∼50%
of all households and ∼90% of all rural households use solid fuels for cooking or heating and these fuels often are burnt in
simple stoves with very incomplete combustion. Exposed women and children often exhibit low birth weight, increased
infant and perinatal mortality, head and neck cancer, and lung cancer although few studies have measured exposure directly.
Today, households that cannot meet the expense of fuels like kerosene, liquefied petroleum gas, and electricity resort to
collecting wood, agricultural residue, and animal dung to use as household fuels. In the more developed countries, solid fuels
are often used for electric power generation providing more than half of the electricity generated in the United States. The
world's coal reserves, which equal approximately one exagram, equal ∼1 trillion barrels of crude oil (comparable to all the
world's known oil reserves) and could last for 600 years. Studies show that the PAHs that are identified in solid fuel
emissions react with NO2 to form direct-acting mutagens. In summary, many of the measured genotoxicants found in both
the indoor and electricity-generating combustors are the same; therefore, the severity of the health effects vary with exposure
and with the health status of the exposed population.
Claxton, L. D. (2014) The history, genotoxicity, and carcinogenicity of carbon-based fuels and their emissions. Part 2: Solid fuels, MUTATION
RESEARCH/REVIEWS IN MUTATION RESEARCH (In Press).
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WASTE
Development of correction factors for landfill gas emission model suiting Indian condition to predict methane
emission from landfills
Abstract - Methane emission from landfill gas emission (LandGEM) model was validated through the results of laboratory
scale biochemical methane potential assay. Results showed that LandGEM model over estimates methane (CH4) emissions;
and the true CH4 potential of waste depends on the level of segregation. Based on these findings, correction factors were
developed to estimate CH4 emission using LandGEM model especially where the level of segregation is negligible or does
not exist. The correction factors obtained from the study were 0.94, 0.13 and 0.74 for food waste, mixed un-segregated
municipal solid waste (MSW) and vegetable wastes, respectively.
Sil, A., S. Kumar, & J. W.C. Wong (2014) Development of correction factors for landfill gas emission model suiting Indian condition to predict
methane emission from landfills, BIORESOURCE TECHNOLOGY 168:97-99.
Methane production in simulated hybrid bioreactor landfill
Abstract - The aim of this work was to study a hybrid bioreactor landfill technology for landfill methane production from
municipal solid waste. Two laboratory-scale columns were operated for about ten months to simulate an anaerobic and a
hybrid landfill bioreactor, respectively. Leachate was recirculated into each column but aeration was conducted in the hybrid
bioreactor during the first stage. Results showed that leachate pH in the anaerobic bioreactor maintained below 6.5, while in
the hybrid bioreactor quickly increased from 5.6 to 7.0 due to the aeration. The temporary aeration resulted in lowering
COD and BOD5 in the leachate. The volume of methane collected from the hybrid bioreactor was 400 times greater than
that of the anaerobic bioreactor. Also, the methane production rate of the hybrid bioreactor was improved within a short
period of time. After about 10 months’ operation, the total methane production in the hybrid bioreactor was 212 L
(16 L/kgwaste).
Xu, Q., X. Jin, Z. Ma, H. Tao, & J. H. Ko (2014) Methane production in simulated hybrid bioreactor landfill, BIORESOURCE
TECHNOLOGY 168:92-96.
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Extraction of soluble substances from organic solid municipal waste to increase methane production
Abstract - This work deals with the analysis of the methane production from Mexico City’s urban organic wastes after
separating soluble from suspended substances. Water was used to extract soluble substances under three different water to
waste ratios and after three extraction procedures. Methane production was measured at 35 °C during 21 days using a
commercial methane potential testing device. Results indicate that volatile solids extraction increases with dilution rate to a
maximum of 40% at 20 °C and to 43% at 93 °C. The extracts methane production increases with the dilution rate as a result
of enhanced dissolved solids extraction. The combined (extract and bagasse) methane production reached, in 6 days, 66% of
the total methane produced in 21 days. The highest methane production rates were measured during the first six days.
Campuzano, R., & S. González-Martínez (2014) Extraction of soluble substances from organic solid municipal waste to increase methane
production, BIORESOURCE TECHNOLOGY (In Press).
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TRANSPORT & INDUSTRY
Air pollutant emissions from on-road vehicles in China, 1999–2011
Abstract - The on-road vehicular emission in China from 1999 to 2011 was estimated, based on the emission factors of
vehicles with different emission standards calculated by the COPERT model. The CO, NMVOC, NOX, BC and OC
emissions changed from 19.7 Tg, 4.4 Tg, 2.3 Tg, 47.1 Gg and 74.4 Gg in 1999 to 32.7 Tg, 4.1 Tg, 7.6 Tg, 177.6 Gg and 101.5
Gg in 2011, respectively. The general trend for CO, NOX and BC was increasing, while the tendency for NMVOC and OC
was firstly increase before 2002 and then decrease from 2003. The spatial analysis results showed that high emissions
occurred in developed provinces (Guangdong, Shandong, Hebei, Jiangsu and Henan). The correlation between vehicular
emissions and GDP were further investigated and good linear correlation was found. The not-obvious change of the interannual (1999–2011) fitted straight line slope and the sustained increasing emissions for NOX and BC suggested that the
challenge of mitigating vehicular NOX and BC emissions is severe in China. The contribution from different vehicle types
was also analyzed. Passenger car (PC) and motorcycle (MC) was the main contributor to the CO and NMVOC emissions.
However, the contribution ratio of MC was decreasing from 36.6% and 68.8% in 1999 to 15.7% and 25.7% in 2011. Heavy
duty truck (HDT) was the dominant contributor to NOX, BC and OC, with proportions of 58.9%, 57.6% and 52.8% in
2011, respectively. In addition, the uncertainty of the estimated emissions was also assessed based on the Monte Carlo
simulation.
Lang, J., S. Cheng, Y. Zhou, Y. Zhang, & G. Wang (2014) Air pollutant emissions from on-road vehicles in China, 1999–2011,
SCIENCE OF THE TOTAL ENVIRONMENT 496:1-10.
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FOSSIL FUELS
Methane emissions from natural gas production and use: reconciling bottom-up and top-down
measurements
Abstract - Methane emissions from the natural gas supply chain are a key factor in determining the greenhouse gas footprint
of natural gas production and use. Recent estimates of these emissions have varied widely, because of the large population of
sources, because of different measurement and estimation approaches, and because of extreme values of emission rates from
individual sources that are much larger than population average values of emission rates from sources in the same category (a
‘fat-tail’ distribution). Reconciling differences between ambient methane concentration measurements (top-down methods)
and direct measurement of emissions from individual sources (bottom-up methods) is critical to understanding methane
emissions from the natural gas supply chain. A combination of top-down and bottom-up approaches is recommended.
Allen, D. T. (2014) Methane emissions from natural gas production and use: reconciling bottom-up and top-down
measurements, CURRENT OPINION IN CHEMICAL ENGINEERING 5:78-83.
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CROSS CUTTING & OTHER SLCP SOURCE SECTORS
Review on greenhouse gas emissions from pig houses: Production of carbon dioxide, methane and nitrous
oxide by animals and manure
Abstract - The environmental impacts of livestock production are attracting increasing attention, especially the emission of
greenhouse gases (GHGs). Currently, pork is the most widely consumed meat product in the world, and its production is
expected to grow in the next few decades. This paper deals with the production of carbon dioxide (CO2), methane (CH4) and
nitrous oxide (N2O) by animals and by manure from pig buildings, with a focus on the influence of rearing techniques and
nutrition. GHG emissions in piggeries originate from animals through CO2exhalation and CH4 enteric fermentation, and
from manure through the release of CO2, CH4 and N2O. The level of the CO2 exhalation (E-CO2, pig) depends on the
physiological stage, the body weight (BW), the production level and the feed intake of the animals concerned. Enteric
CH4 (E-CH4, pig) is principally related to dietary fibre intake and the fermentative capacity of the pig’s hindgut. Based on a
review of the literature, the following equations are proposed in order to estimate E-CO2, pig (in kg day−1) and E-CH4,pig (in g
day−1) for fattening pigs: E-CO2, pig = 0.136 × BW0.573; E-CH4,pig = 0.012 × dRes; with BW (in kg) and dRes for digestible
residues (in g day−1). Numerous pathways are responsible for GHG production in manure. In addition, the microbial,
physical and chemical properties of manure interact and modulate the level of emissions. Influencing factors for removal
systems for both liquid and solid fractions of manure have been investigated. A large range of parameters showing an impact
on the level of GHG production from pig houses has been reported. However, few of these can be considered
unquestionably as GHG mitigation techniques because some strategies have shown contradictory effects depending on the
gas, the circumstances and the study. Nevertheless, frequent manure removal seems to be an efficient means to reduce
concurrently CO2-, CH4- and N2O-emissions from pig buildings for both slatted and bedded floor systems. Manure removal
operations may be associated with specific storage conditions and efficient treatment in order to further reduce emissions.
Several feeding strategies have been tested to decrease GHG emissions but they seem to be ineffective in reducing emissions
both significantly and durably. In general, good management practices that enhance zootechnical performance will have
beneficial consequences on GHG emission intensity. Taking into account the results described in the literature regarding
CO2-, CH4- and N2O-production from animals and manure in pig houses, we estimate total GHG emissions to 448.3 kg
CO2equiv. per slaughter pig produced or 4.87 kg CO2equiv. per kg carcass. The fattening period accounts for more than
70% of total emissions, while the gestation, lactation and weaning periods each contribute to about 10% of total emissions.
Emissions of CO2, CH4and N2O contribute to 81, 17 and 2% of total emissions from pig buildings, representing 3.87, 0.83
and 0.11 kg CO2equiv. per kg carcass, respectively.
Philippe, F.-X., & B. Nicks (2014) Review on greenhouse gas emissions from pig houses: Production of carbon dioxide, methane and nitrous
oxide by animals and manure, AGRICULTURE, ECOSYSTEMS & ENVIRONMENT 199:10-25.
Fuel stacking in India: Changes in the cooking and lighting mix, 1987–2010
Abstract - In the developing world, households often stack multiple fuels. In the case of India, they use both kerosene and
electricity for lighting while cooking with both LPG (liquefied petroleum gas) and traditional biomass. Existing scholarship
on fuel stacking largely relies on small surveys and does not investigate change over time. We leverage the nationally
representative NSS (National Sample Survey) of India in 1987 and 2010, finding that fuel stacking is decreasing in lighting, as
people substitute electricity for kerosene, but increasing in cooking, as LPG does not replace traditional biomass. We also
exploit a two-stage statistical model to analyze individual household's decision of fuel stacking. The most important finding
is that, while a high household income reduces fuel stacking for lighting, it no longer does so in 2010 for cooking. The main
policy implication of the study is that much more aggressive efforts are needed to deal with problems associated with
biofuels, such as indoor air pollution, than to induce the switch from kerosene to electricity. The statistical model offers a
considerable improvement over existing alternatives in the literature on household energy access.
Cheng, C., & J. Urpelainen (2014) Fuel stacking in India: Changes in the cooking and lighting mix, 1987–2010, ENERGY (In Press).
27
Energy poverty reduction by fuel switching. Impact evaluation of the LPG conversion program in
Indonesia
Abstract - In low- and middle-income countries, Liquefied Petroleum Gas (LPG) can be an attractive alternative to the
widespread use of traditional kerosene. Not only is LPG a relatively clean, safe and cost-effective fuel for households, its
large-scale adoption also reduces the heavy burden of kerosene consumption subsidies on government budgets. Against this
background, we evaluate the impact of a large government program to substitute LPG for kerosene in Indonesia. Using a
household survey across urban, suburban and rural regions we find that this program was very effective in causing a large
scale shift from kerosene to LPG. This shift was positively influenced by level of education, household size and household
income. Contradicting the energy-ladder model, the LPG program, reinforced by an increase in the price of kerosene, led to
increased stacking of fuels, including increasing consumption of both electricity and traditional biomass. In addition, our
analysis shows that the LPG program failed to substantially reduce the overall number of energy-poor people, but it has been
effective in alleviating extreme energy-poverty. Finally, we find that medium and higher income households in suburban
areas benefitted most from the LPG program.
Andadari, R. K., P. Mulder, & P. Rietveld (2014) Energy poverty reduction by fuel switching. Impact evaluation of the LPG conversion
program in Indonesia, ENERGY POLICY 66:436-449.
Source apportionment of PM2.5 in the harbour–industrial area of Brindisi (Italy): Identification and
estimation of the contribution of in-port ship emissions
Abstract - Harbours are important for economic and social development of coastal areas but they also represent an
anthropogenic source of emissions often located near urban centres and industrial areas. This increases the difficulties in
distinguishing the harbour contribution with respect to other sources. The aim of this work is the characterisation of main
sources of PM2.5 acting on the Brindisi harbour–industrial area, trying to pinpoint the contribution of in-port ship emissions
to primary and secondary PM2.5. Brindisi is an important port-city of the Adriatic Sea considered a hot-spot for
anthropogenic environmental pressures at National level. Measurements were performed collecting PM2.5 samples and
characterising the concentrations of 23 chemical species (water soluble organic and inorganic carbon; major ions: SO42 −,
NO3−, NH4+, Cl−, C2O42 −, Na+, K+, Mg2 +, Ca2 +; and elements: Ni, Cu, V, Mn, As, Pb, Cr, Sb, Fe, Al, Zn, and Ti).
These species represent, on average, 51.4% of PM2.5 and were used for source apportionment via PMF. The contributions
of eight sources were estimated: crustal (16.4 ± 0.9% of PM2.5), aged marine (2.6 ± 0.5%), crustal carbonates (7.7 ± 0.3%),
ammonium sulphate (27.3 ± 0.8%), biomass burning-fires (11.7 ± 0.7%), traffic (16.4 ± 1.7 %), industrial (0.4 ± 0.3%) and a
mixed source oil combustion–industrial including ship emissions in harbour (15.3 ± 1.3%). The PMF did not separate the inport ship emission contribution from industrial releases. The correlation of estimated contribution with meteorology showed
directionality with an increase of oil combustion and sulphate contribution in the harbour direction with respect to the
direction of the urban area and an increase of the V/Ni ratio. This allowed for the use of V as marker of primary ship
contribution to PM2.5 (2.8% +/− 1.1%). The secondary contribution of oil combustion to non-sea-salt-sulphate, nssSO42
−, was estimated to be 1.3 μg/m3 (about 40% of total nssSO42 − or 11% of PM2.5).
Cesari, D., A. Genga, P. Ielpo, M. Siciliano, G. Mascolo, F.M. Grasso, & D. Contini (2014) Source apportionment of PM2.5 in the
harbour–industrial area of Brindisi (Italy): Identification and estimation of the contribution of in-port ship emissions, SCIENCE OF THE
TOTAL ENVIRONMENT 497–498:392-400.
Impact of inland shipping emissions on elemental carbon concentrations near waterways in The
Netherlands
Abstract - This study aims to quantify the impact of black carbon from inland shipping on air quality, expressed as elemental
carbon (EC) near inland waterways in The Netherlands. Downwind measurements of particle numbers and EC were used to
establish emission factors for EC from inland shipping using inverse modelling. These emission factors were combined with
data on energy consumption to derive annual average emissions rates for all Dutch waterways. A line source model was
applied to compute the contribution of inland shipping to annual average EC concentrations for around 140,000 people
living within 200 m of busy waterways in The Netherlands. The results showed that they are exposed to additional EC
concentrations of up to 0.5 μg EC per m3 depending on the shipping volume and distance from the waterway. In view of
the envisaged growth in water transport, this underlines the need to reduce combustion emissions from inland shipping.
Targeting “gross” polluters may be the most effective approach since 30% of ships cause more than 80% of the total
emissions.
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Keuken, M.P., M. Moerman, J. Jonkers, J. Hulskotte, H.A.C. Denier van der Gon, G. Hoek, & R.S. Sokhi (2014) Impact of
inland shipping emissions on elemental carbon concentrations near waterways in The Netherlands, ATMOSPHERIC ENVIRONMENT 95:1-9.
Aircraft engine exhaust emissions and other airport-related contributions to ambient air pollution: A
review
Abstract - Civil aviation is fast-growing (about +5% every year), mainly driven by the developing economies and
globalisation. Its impact on the environment is heavily debated, particularly in relation to climate forcing attributed to
emissions at cruising altitudes and the noise and the deterioration of air quality at ground-level due to airport operations.
This latter environmental issue is of particular interest to the scientific community and policymakers, especially in relation to
the breach of limit and target values for many air pollutants, mainly nitrogen oxides and particulate matter, near the busiest
airports and the resulting consequences for public health. Despite the increased attention given to aircraft emissions at
ground-level and air pollution in the vicinity of airports, many research gaps remain. Sources relevant to air quality include
not only engine exhaust and non-exhaust emissions from aircraft, but also emissions from the units providing power to the
aircraft on the ground, the traffic due to the airport ground service, maintenance work, heating facilities, fugitive vapours
from refuelling operations, kitchens and restaurants for passengers and operators, intermodal transportation systems, and
road traffic for transporting people and goods in and out to the airport. Many of these sources have received inadequate
attention, despite their high potential for impact on air quality. This review aims to summarise the state-of-the-art research
on aircraft and airport emissions and attempts to synthesise the results of studies that have addressed this issue. It also aims
to describe the key characteristics of pollution, the impacts upon global and local air quality and to address the future
potential of research by highlighting research needs.
Masiol, M., R. M. Harrison (2014) Aircraft engine exhaust emissions and other airport-related contributions to ambient air pollution: A
review, ATMOSPHERIC ENVIRONMENT 95:409-455
Relating urban airborne particle concentrations to shipping using carbon based elemental emission ratios
Abstract - This study demonstrates a novel method for testing the hypothesis that variations in primary and secondary
particle number concentration (PNC) in urban air are related to residual fuel oil combustion at a coastal port lying 30 km
upwind, by examining the correlation between PNC and airborne particle composition signatures chosen for their sensitivity
to the elemental contaminants present in residual fuel oil. Residual fuel oil combustion indicators were chosen by comparing
the sensitivity of a range of concentration ratios to airborne emissions originating from the port. The most responsive were
combinations of vanadium and sulphur concentration ([S], [V]) expressed as ratios with respect to black carbon
concentration ([BC]). These correlated significantly with ship activity at the port and with the fraction of time during which
the wind blew from the port.
The average [V] when the wind was predominantly from the port was 0.52 ng m−3 (87%) higher than the average for all
wind directions and 0.83 ng m−3 (280%) higher than that for the lowest vanadium yielding wind direction considered to
approximate the natural background. Shipping was found to be the main source of V impacting urban air quality in Brisbane.
However, contrary to the stated hypothesis, increases in PNC related measures did not correlate with ship emission
indicators or ship traffic. Hence at this site ship emissions were not found to be a major contributor to PNC compared to
other fossil fuel combustion sources such as road traffic, airport and refinery emissions.
Johnson, G. R., A. M. Juwono, A. J. Friend, H. Cheung, E. Stelcer, D. Cohen, G. A. Ayoko, & L. Morawska (2014) Relating
urban airborne particle concentrations to shipping using carbon based elemental emission ratios, ATMOSPHERIC ENVIRONMENT 95:525536.
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