Indoor air pollution
Framework:
1. Introduction
2. Magnitude of indoor air pollution
3. Pollution trends in India
4. Source of Indoor air pollution
5. Adverse health effects of Indoor air pollutants
6. Standards and guidelines for Indoor air pollution
7. Prevention of Indoor air pollution
8. National Programme on Improved Chulhas (NPIC)
9. National Biomass Cook stoves Programme(NBCP)
1. Introduction
Clean air is a basic requirement of life. The quality of air inside homes, offices, schools,
day care centres, public buildings, health care facilities or other private and public
buildings where people spend a large part of their life is an essential determinant of
healthy life and people’s well-being. Hazardous substances emitted from buildings,
construction materials and indoor equipment or due to human activities indoors, such as
combustion of fuels for cooking or heating, lead to a broad range of health problems and
may even be fatal.
According to a WHO assessment of the burden of disease due to air pollution, more than
two million premature deaths each year can be attributed to the effects of urban outdoor
air pollution and indoor air pollution (from the burning of solid fuels). More than half of
this disease burden is borne by the populations of developing countries.
GBD has ranked air pollution as one of the top 10 killers in the world, and the sixth most
dangerous killer in South Asia. In fact, particulate air pollution is now just three places
behind indoor air pollution, which is the second highest killer in India.
Basic definitions
Before discussing in detail the sources of air pollutants it is necessary to establish a few basic
principles that will place the information on sources in context.
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Air pollutants may be either emitted into the atmosphere or formed within the atmosphere
itself.
Primary air pollutants
Primary air pollutants are those that are emitted into the atmosphere from a source such as a
factory chimney or exhaust pipe, or through suspension of contaminated dusts by the wind. In
principle, therefore, it is possible to measure the amounts emitted at the source itself.
This is relatively straightforward in terms of the factory chimney or vehicle exhaust pipe; it
becomes very much more difficult when considering diffuse sources such as wind-blown
dusts.
Secondary air pollutants
Secondary air pollutants are those formed within the atmosphere itself. They arise from
chemical reactions of primary pollutants, possibly involving the natural components of the
atmosphere, especially oxygen and water. The most familiar example is ozone, which arises
almost entirely from chemical reactions that differ with altitude within the atmosphere.
Gaseous air pollutants
Gaseous air pollutants are those present as gases or vapours, i.e. as individual small
molecules capable of passing through filters provided they do not adsorb to or chemically
react with the filter medium. Gaseous air pollutants are readily taken into the human
respiratory system, although if water-soluble they may very quickly be deposited in the upper
respiratory tract and not penetrate to the deep lung.
Particulate air pollutants
Particulate air pollutants comprise material in solid or liquid phase suspended in the
atmosphere. Such particles can be either primary or secondary and cover a wide range of
sizes. Newly formed secondary particles can be as small as 1–2 nm in diameter (1 nm = 10–9
m), while coarse dust and sea salt particles can be as large as 100 μm (1 μm = 10–6 m) or 0.1
mm in diameter. Particulate air pollutants have very diverse chemical compositions that are
highly dependent on their source. They are also diverse in terms of particle size.
Fig. 1 illustrates the range of sizes (on a logarithmic scale) together with the ranges where
certain important components are typically encountered. It shows also the PM10, PM2.5 and
ultrafine particle fractions, which are typically those, measured within the atmosphere for the
purposes of health effects studies; the first two fractions are also used for compliance
monitoring.
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Fig. 1. Size range of airborne particles, showing the health-related ultrafine, PM2.5 and
PM10 fractions and the typical size range of some major components
.
2. Magnitude of the problems
Worldwide:
Approximately half the world’s population and up to 90% of rural households in developing
countries still rely on unprocessed biomass fuels such as wood, dung and crop residues. A
recent report of the World Health Organization (WHO) asserts the rule of 1000 which states
that a pollutant released indoors is one thousand times more likely to reach people’s lung than
a pollutant released outdoors. More than 1.6 million people, mainly women and children, die
prematurely each year after breathing high levels of indoor smoke. This represents
approximately twice the estimated mortality due to outdoor pollution. Children and senior
citizens can be more vulnerable to indoor pollution because their immunity may be
compromised.
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An estimated 3.5 million deaths in 2010 were attributed to household air pollution globally.
According to WHO estimates, while 50% of the global population uses solid fuels for their
energy needs, 61% of households in the Region use solid fuels, which is second only to
Africa at 77%. Household air pollution is largely a problem of poverty and lack of access to
clean fuels.
Increase in death toll: Air pollution-related diseases cause 3.2 million deaths worldwide
every year. This has increased from 800,000, last estimated by GBD in 2000—a whopping
300 per cent increase. About 74 million healthy life years are lost annually.
Ranked among the top 10 killers in the world: In South Asia, air pollution has been ranked
just below blood pressure, tobacco smoking, indoor air pollution, poor intake of fruits and
diabetes. Everyone rich and poor is vulnerable.
Two-thirds of the death burden from outdoor air pollution occurs in developing Asia: In
2010, particulate air pollution in Asia led to over 2.1 million premature deaths and 52 million
years of healthy life lost, which is two-thirds of the worldwide burden. Killer outdoor air
contributes to 1.2 million deaths in East Asia where economic growth and motorization are
taking over, and 712,000 deaths in South Asia (including India) which is at the take-off stage.
This is much higher than the combined toll of 400,000 in EU 27, Eastern Europe, and Russia.
India:
The 1991 National Census included for the first time a question about the primary household fuel
used and reflected that about 95% of the rural population still relied primarily on biomass fuels (dung,
crop residues, and wood). A small fraction uses coal, which means about 97% of households relied
principally on these unprocessed solid fuels. Nationwide, some 81% of all households relied on these
fuels; 3% used coal and 78% used biomass. An independent probability-weighted national survey of
89,000 households in 1992 derived very similar results.
It has been estimated that about half a million women and children die each year from indoor
air pollution in India. Compared to other countries, India has among the largest burden of
disease due to the use of dirty. (ICMR)
Globally, indoor smoke ranks tenth as a risk factor for global burden of disease, according to
a 2002 World Health Organisation report. But it ranks third for the Indian burden of disease.
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Air pollution is the fifth leading cause of death in India, with 620,000 premature deaths. This
is up from 100,000 in 2000 – a six-fold increase.
Respiratory and cardiovascular diseases key reasons for air pollution-induced
premature deaths: These diseases include stroke (25.48 per cent), chronic obstructive
pulmonary disease (17.32 per cent), Ischemic heart disease (48.6 per cent), lower respiratory
infections (6.4 per cent), and trachea, bronchus and lung cancer (2.02 per cent).
3. Pollution trends in India
In the wake of the GBD findings, Centre for Science and Environment (CSE) has analysed the
latest air quality data available with the Central Pollution Control Board for 2010. Of the 180
cities monitored for SO2, NO2 and PM10, only two, Malappuram and Pattanamthitta in Kerala
meet the criteria of low pollution (50% below the standard) for all air pollutants.
The trends:

Close to half the cities are reeling under severe particulate pollution while newer
pollutants like nitrogen oxides, ozone and air toxics are increasing the public health
challenge.

Vulnerable urban population: Half of the urban population breathes air laced with
particulate pollution that has exceeded the standards. As much as one-third of the
population is exposed to critical levels of particulate pollution. Smaller and more
obscure cities are among the most polluted.

More cities in grip of PM10: About 78 per cent cities exceed the PM10 standard.
Ninety cities have critical levels of PM10; 26 have the most critical levels, exceeding
the standard by over three times. Gwalior, West Singhbhum, Ghaziabad, Raipur, and
Delhi are the top five critically polluted cities.

More cities in grip of NO2: About 10 per cent of the cities exceed the NO2 standard.
Of these, about nine have critical levels. Howrah, Barrackpore, Badlapur, Ulhasnagar
and Asansol are the five top critically polluted cities.

State of SO2 pollution: One city—Lote in Maharashtra exceeds the SO2 standard.
Moderate levels of SO2 are noted in Jamshedpur and Saraikela Kharsawan in
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Jharkhand; Chandrapur, Badlapur, Ulhasnagar, and Pune in Maharashtra; Ghaziabad
and Khurja in UP, Dehradun in Uttarakhand and Marmagao and Curchorem in Goa.

Cities with double-trouble—particulates and NO2: Howrah, Barrackpore, Asansol,
Durgapur, Sankrail, Raniganj, Kolkata (West Bengal), Badlapur and Ulhasnagar
(Maharashtra) have critical levels of NO2 and PM10. Delhi, Haldia, Bicholim,
Jamshedpur, Meerut, Noida, Saraikela Kharsawan, Jalgaon and Raipur have high levels
of NO2 as well as critical levels of PM10.

Worsening trend since 2005: The PM10 monitoring network has doubled between
2005 and 2010 from 96 to 180 cities. During this period, cities with low level of
pollution have fallen from 10 to 2, while the number of critically polluted cities has
increased from 49 to 89. In 2005 about 75 per cent cities exceeded the standard. In
2010, 78 per cent were found exceeding the standard.

NO2 monitoring has expanded from 100 cities in 2005 to 177 in 2010. In 2005 only one
city had exceeded the standard for NO2; in 2010, 19 cities have exceeded the standard.
The tightening of the national ambient air quality standards has also changed the air
quality profile of the cities.

Stabilisation in some cities: Some mega cities that have initiated some pollution
control action in recent years have witnessed either stabilisation or some decrease in the
levels.
Indoor air pollution
The indoor environment represents an important microenvironment in which people spend a
large part of their time each day. As a result, indoor air pollution, originating from both
outdoor and indoor sources, is likely to contribute more to population exposure than the
outdoor environment. The extent and magnitude of consequent health risks, however, remain
poorly understood. The large number of indoor air pollutants, including chemical and
biological contaminants, and the influence of a variety of factors such as the nature and
location of sources, air exchange between indoor and outdoor environments and individual
behaviour make accurate estimations of health effects very difficult.
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3. Source of Indoor air pollution
The major sources of indoor air pollution worldwide include combustion of solid fuels
indoors, tobacco smoking, outdoor air pollutants, emissions from construction materials and
furnishings, and improper maintenance of ventilation and air conditioning systems. The 1991
National Census for the first time inquired about the fuel used for coking. It revealed that
about 90% of the rural population relied upon the biomass fuels like animal dung, crop
residues and wood. A small portion used coal. Nation-wide about 78% of the population
relied upon the biomass fuels and 3% on coal.
Principal sources of pollutants of indoor air:
(i) Combustion, (ii) building material, (iii) the ground under the building, and (iv) bio
aerosols.
In developed countries the most important indoor air pollutants are radon, asbestos, volatile
organic compounds, pesticides, heavy metals, animal dander, mites, moulds and
environmental tobacco smoke. However, in developing countries the most important indoor
air pollutants are the combustion products of unprocessed solid biomass fuels used by the
poor urban and rural folk for cooking and heating.
The type of fuels used by a household is determined maily by its economic status. In the
energy ladder, biomass fuels namely animal dung, crop residues and wood, which are the
dirtiest fuels, lie at the bottom and are used mostly by very poor people. Electricity, which is
the most expensive, lies at the top of ladder and it is also the cleanest fuel.
Table Major health-damaging pollutants generated from indoor sources
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Indoor air quality is influenced by:
 Outdoor air pollution: vehicles and industrial plants
 Second-hand tobacco smoke
 Fuels used for heating and cooking
 Confined and poorly ventilated spaces
 Overcrowded homes and insufficient living space
 Customs, habits, traditions
 Level of economic development:
 Industrialized /developing countries
4. ADVERSE HEALTH EFFECTS OF AIR POLLUTANTS
Exposure to air pollution has been associated with a variety of adverse health effects. Most of
the recent evidence focuses on respiratory and cardiovascular effects attributed to short- and
long-term exposures, as well as on the development of pregnancy-related outcomes. From a
public health point of view, it is important to acknowledge that the total impact of air
pollution on the population is likely to be dominated by the less severe health effects such as
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subclinical and symptomatic events. The proportion of the exposed population affected by
those outcomes is much larger than that affected by more severe events such as emergency
admission to hospital and death.
Acute:
 Irritation of the mucous membranes (eyes, nose, throat)
 Cough, wheeze, chest tightness
 Increased airway responsiveness to allergens
 Increased incidence of acute respiratory illness: "cold", pneumonia, otitis media
 Tracheobronchitis
 Exacerbation of asthma
 Work absenteeism
 School absenteeism
Chronic:
 Long-term exposure decreases lung growth
 Increased susceptibility to chronic obstructive lung diseases, including asthma
Mortality due to cardiovascular and respiratory disease
 Chronic respiratory disease incidence and prevalence (asthma, COPD, chronic
pathological changes)
 Chronic changes in physiologic functions
 Lung cancer
 Chronic cardiovascular disease
 Other
SPECIFIC DISEASES ASSOCIATED WITH INDOOR AIR POLLUTANT EXPOSURE
Respiratory illness, cancer, tuberculosis, perinatal outcomes including low birth weight, and
eye diseases are the morbidities associated with indoor air pollution.
A .Respiratory Illness
The most commonly reported and obvious health effect of indoor air pollutants is the increase
in the incidence of respiratory morbidity. Studies by the NIOH on the prevalence of
respiratory symptoms in women using traditional fuels (biomass) (n=175) and LPG (n=99),
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matched for economic status and age, indicated that the relative risk (with 95% C.I.) for
cough, and shortness of breath (dyspnoea) was 3.2 (1.6-6.7), and 4.6 (1.2-18.2).
Childhood acute respiratory infections
1. Acute lower respiratory infections
Acute respiratory infections (ARIs) are the single most important cause of mortality in
children aged less than 5 years, accounting for around 3-5 million deaths annually in this age
group. Many studies in developing countries have reported on the association between
exposure to indoor air pollution and acute lower respiratory infections. Evidence from 13
studies in developing countries indicate a odds ratio range of 2–3,3 i.e. young children living
in solid-fuel using households have two to three times more risk of serious ARI than
unexposed children after adjustment for potential confounders including socio-economic
status.(Smith et al., 2000a).
2. Upper respiratory tract infections and otitis media
There is strong evidence that exposure to environmental tobacco smoke causes middle ear
disease. A recent meta-analysis reported an odds ratio of 1.48 (1.08-2.04) for recurrent otitis
media if either parent smoked, and one of 1.38 (1.23-1.55) for middle ear effusion in the
same circumstances. A clinic based case-control study of children in rural New York state
reported an adjusted odds ratio for otitis media, involving two or more separate episodes, of
1.73 (1.03-2.89) for exposure to wood burning stoves.
3. Chronic pulmonary diseases:
Chronic obstructive pulmonary disease and chronic cor pulmonale
In developed countries, smoking is responsible for over 80% of cases of chronic bronchitis and for
most cases of emphysema and chronic obstructive pulmonary disease. Such as chronic bronchitis, in
women accounts for about 1.5% of deaths in India, and 16% in China. Evaluation of eight studies in
developing countries indicates an adjusted odds-ratio range of 2–4 for women cooking over biomass
fires for many years (Bruce et al., 2000; Smith, 2000).
Combining these risk estimates with the estimated pattern of exposures (solid-fuel use) and
background health conditions in India, something like 500,000 premature deaths, which when added
to the associated morbidity, produces some 6–7% of the national burden of disease, may be
attributable to indoor air pollution (IAP). Extrapolating to the rest of the world on the basis of regional
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use of solid fuels and regional population and health conditions, solid fuel use in developing countries
might thus be responsible for nearly 4% of the global burden of disease and well-exceed 1 million
premature deaths per year (WHO, 1997).
Padmavati and colleagues pointed out to the relationship between exposure to indoor air pollutants
and chronic obstructive lung disease leading to chronic cor pulmonale. These studies showed that in
India, the incidence of chronic cor pulmonale is similar in men and women despite the fact that 75%
of the men and only 10% women are smokers.
Pneumoconiosis
Pneumoconiosis is a disease of industrial workers occupationally exposed to fine mineral dust
articles over a long time. The disease is most frequently seen in miners. Cases of respiratory
morbidity who did not respond to routine treatment and whose radiological picture resembled
pneumoconiosis have been reported in Ladakh.
However, there are no industries or mines in any part of Ladakh and therefore exposure to
dust from these sources was ruled out.
Two factors considered responsible for the development of this respiratory morbidity were
(i)
Exposure to dust from dust storms. In the spring dust storms occur in many parts of
Ladakh. During these storms the affected villages are covered by a thick blanket of
fine dust, and the inhabitants are exposed to a considerable amount of dust for several
days. The frequency, duration and severity of these dust storms vary considerably
from village to village;
(ii)
Exposure to soot – due to the severe cold in Ladakh, ventilation in the houses is kept
at a minimum. The fire place is used for both cooking and heating purposes. To
conserve fuel during non-cooking periods, the wood is not allowed to burn quickly
but is kept smouldering to prolong its slow heating effect. The inmates are thus
exposed to high concentrations of soot. The clinico- radiological investigations of
449 randomly selected villagers from three villages having mild, moderate and severe
dust storms showed prevalence of pneumoconiosis of 2.0, 20.1 and 45.3%
respectively.
The chest radiographs of the villagers showed radiological characteristics which were
indistinguishable from those found in miners and industrial workers suffering from
pneumoconiosis. The dust concentrations in the kitchens without chimneys varied from 3.22
to 11.30 mg/m3 with a mean of 7.50 mg/m3. The free silica content of these dust samples
was below 1%. Dust samples sufficient to allow measurement of the dust concentrations
could not be collected during the periods of dust storms.
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Thus, the results of medical and radiological investigations positively established the
occurrence of pneumoconiosis in epidemic proportion. Exposure to free silica from dust
storms and soot from domestic fuel were suggested as the causes of pneumoconiosis. Low
oxygen levels or some other factor associated with high altitude may be an important
contributory factor in causation of pneumoconiosis because it has been reported that the
miners working at high altitude are more prone to develop pneumoconiosis than their
counterparts exposed to the same levels of dust and working in the mines at normal altitude.
Lung Cancer
The link between lung cancer in Chinese women and cooking on an open coal stove has been
well established.
Smoking is a major risk factor for lung cancer; however, about two-thirds of the lung cancers
were reported in non-smoking women in China, India and Mexico. The presence of previous
lung disease, for example tuberculosis which is common in Indian women, is a risk factor for
development of lung cancer in non-smokers.
Typical range of odds ratios for non-smoking women in 20+ Chinese studies is 3–5 (Smith and Liu,
1994).The smoke from biomass fuels contain a large number of compounds such as poly
aromatic hydrocarbons, formaldehyde, etc. known for their mutagenic and carcinogenic
activities, but there is a general lack of epidemiological evidence connecting lung cancer with
biomass fuel exposure.
Pulmonary Tuberculosis
Analysis of the same Indian national survey found a adjusted risk of 2.7 for solid-fuel using women
(Mishra et al., 1999a), although based on self reported tuberculosis (TB). A clinical study in
Lucknow, India, found similar risks (2.5), although not adjusted for potential confounding (Gupta et
al.1997). A recent case–control study in Mexico City, however, that was both adjusted for potential
confounders and had clinically confirmed TB found an odds ratio of 2.4 for people in households
using wood for cooking (Perez-Padilla et al., 2001).
5. Cataract
During cooking particularly with biomass fuels, air has to be blown into the fire from time to
time especially when the fuel is moist and the fire is smouldering. This causes considerable
exposure of the eyes to the emanating smoke. An adjusted odds ratio of 1.3 for blindness in
women was found in biomass-using homes in a large (89,000 household) Indian national survey
Corrected for a range of potentially confounding socio-economic factors (Mishra et al., 1999b). A
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Delhi clinical case–control study found similar risks 1.6 for cataract-caused blindness after adjustment
(Mohan et al., 1989), while another case–control study in Nagpur, India, found an adjusted odds ratio
of 2.4 (Zodpey and Ughade, 1999).
An analysis of over 170,000 people in India yielded an adjusted odds ratio for reported
partial or complete blindness of 1.32 (1.16-1.50) in respect of persons mainly using biomass
fuel compared with other fuels after adjusting for socio-economic, housing and geographical
variables; there was a lack of information on smoking, nutritional state, and other factors that
might have influenced the prevalence of cataract.
6. Adverse Pregnancy Outcome
Stillbirth, low birth weight and early infant death have been associated with outdoor air pollution and
active and passive smoking in developed countries and in a few developing-country studies of
households using solid fuels (Mavalankar et al., 1991; Boy et al., 2002).
Low birth weight (LBW) is an important public health problem in developing nations
attributed mainly to undernutrition in pregnant women. Low birth weight has serious
consequences including increased possibility of death during infancy. Exposure to carbon
monoxide from tobacco smoke during pregnancy has been associated with LBW. Levels of
carbon monoxide in the houses using biomass fuels are high enough to result in
carboxyhaemoglobin levels comparable to those in smokers. In rural Guatemala, babies born
to women using wood fuel were 63 g lighter than those born to women using gas and
electricity, after adjustment for socio-economic and maternal factors. A study carried out in
Ahmedabad reported an excess risk of 50% of stillbirth among women using biomass fuels
during pregnancy. An association between exposure to ambient air pollution and adverse
pregnancy outcome has been widely reported.
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Other Health Effects Associated with Indoor Air Pollution
Sick Building Syndrome (SBS):
SBS is the occurrence of specific symptoms with unspecified aetiology. SBS is experienced by people
while working or living in a particular building, but which disappear after they leave it. Symptoms
include mucous membrane, skin and eye irritation, chest tightness, fatigue, headache, malaise,
lethargy, lack of concentration, odour annoyance and influenza symptoms. It is assumed that the
interaction of several factors, involving different reaction mechanisms, cause the syndrome, but there
is yet no clear evidence of any exposure-effect relationship.
Building Related Illness (BRI):
BRI is an illness related to indoor exposures to biological and chemical substances (e.g. fungi,
bacteria, endotoxins, mycotoxins, radon, CO, HCHO). It is experienced by some people working or
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living in a particular building and it does not disappear after leaving it. Illnesses include respiratory
tract infections and diseases, legionnaires' disease,cardiovascular diseases and lung cancer.
Table: Mechanisms by which some key pollutants in smoke from domestic sources may
increase the risk of respiratory and other health problems
Indoor air pollutant levels in households using solid fuel: concentrations and exposures:
The majority of households in developing countries burn solid fuels in poorly functioning
earth or metal stoves or use open pits. Incomplete combustion in poorly ventilated kitchens4
thus results in very high levels of indoor air pollution. Well over a hundred studies over the
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last two decades have assessed levels of indoor air pollutants in households using solid fuels.
The methods employed range from collecting questionnaire-based information to quantitative
measurements of household exposures
A global database is now available that documents results of these measurements from about
110 studies in China and about 70 studies in developing countries in Asia, Latin America and
Africa. Although the great majority of studies have performed single-pollutant measurements
on a cross-sectional sample of households, some recent studies have made important
contributions to examining temporal, spatial or multi-pollutant patterns in addition to day-today or seasonal variability in concentrations and exposures. A few have also developed
models to examine the differential contributions of household-level determinants and validate
the use of simpler household-level indicators (that are relatively easy to collect) as a proxy
for household exposures.
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Several studies have suggested that the exposure–response relationship between particulate
pollution and mortality is essentially linear. In a linear relationship, increasing exposures are
associated with increases in the frequency of effects. An important implication of this
apparent linear relationship would be the absence of a no-observable-effect level or limit
value below which effects are not observed. Thus, effects of pollutants occur even at very
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low levels, which may explain why a large proportion of the population is affected by air
pollution. Besides the high frequency of less severe effects, such as demonstrated by changes
in physiological parameters, it is important to consider that some of them may lead to chronic
effects later in life.
Health effects associated with exposure to solid fuel smoke:
Evidence for health effects associated with exposure to smoke from the combustion of
biomass fuels was provided initially by studies on outdoor air pollution as well as by those
dealing with exposure to environmental tobacco smoke. Criteria documents for outdoor air
pollutants published by USEPA, for example, detail the effects of many components also
found in wood smoke, including PM, carbon monoxide, oxides of sulfur and nitrogen and
PAHs.
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In the presence of exposure, the proportion of the population affected by less severe
outcomes is much larger than that affected by the more severe outcomes (Fig. 1). Subclinical
or subtle effects, such as temporary deficits in lung function or pulmonary inflammation, may
occur in most of those exposed while mortality may occur in a few. It is usually the more
susceptible who suffer the more severe effects. Mortality is advanced by days, weeks or even
longer periods in those already ill, and those with a pre-existing medical condition are more
likely to be admitted to hospital or to visit an emergency department.
The total impact of air pollution is then likely to exceed that contributed by the less frequent
but more severe outcomes, and in some cases be dominated by the less severe but more
frequent ones. From a public health point of view, it is important to understand this
relationship for several reasons. Assessment of premature mortality, which up to now has
been the major driver of the policy processes, is but the tip of the iceberg, representing a
small fraction of all effects associated with air pollution.
Fig. 1. Pyramid of health effects associated with air pollution
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6. Standards and guidelines
US EPA standards are illustrated here. 150 μg/m3 PM10 is the 24-hour 99% percentile value, thus it
should be exceeded only on 1% of occasions. The recommended annual mean limit is 50 μg/m3
PM10 (PM10 are respirable particles 10 micrometre (μm) in diameter).
Levels of pollution in homes using biomass fuel
Numerous studies have shown that the levels of particulates are very high, with 24-hour
means of around 1000 μg/m3 PM10, and even exceeding 10 000 μg/m3 PM10 when sampling
is carried out during use of an open fire. It is reasonable to compare the EPA recommended
annual mean limit of 50 μg/m3 PM10 with the typical 24-hour mean for a home in which
biomass fuel is used, of 1000 μg/m3 PM10 quoted, as this latter value is typical of the level
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every day (thus, annual mean levels can be expected to be around 1000 μg/m3 PM10). This
comparison shows that average pollution levels are around 20 times the EPA recommended limit.
Ambient pollution and personal exposure
Two important components are (a) the level in the home, and (b) the length of time for which each
person in the home is exposed to that level. We know that typically women and young children (until
they can walk), and girls (as they learn kitchen skills) are often exposed for at least 3–5 hours a day,
often more. In some communities, and where it is cold, exposure will be for a much longer period
each day.
7. Preventive of Indoor air pollution
Adequate evidence exists to indicate that indoor air pollution in India is responsible for a high
degree of morbidity and mortality warranting immediate steps for intervention.
The prevention programme should include:
(i) Public awareness; (ii) Change in pattern of fuel use; (iii) Modification in stove design; (iv)
Improvement in the ventilation; and (v) Multispectral approach.
1. Public Awareness
The first and the most important step in the prevention of illnesses resulting from biomass
fuels is to educate the public, administrators and politicians to ensure their commitment
and promoting awareness of the long-term health effects on the part of users. This may
lead to people finding ways of minimizing exposure through better kitchen management
and infant protection.
2. Change in Pattern of Fuel Use
The choice of fuel is mainly a matter of availability, affordability and habit. The gobar
gas plant which uses biomass mainly dung has been successfully demonstrated to produce
economically viable quantities of cooking gas and manure. Recently, the Government of
Andhra Pradesh has introduced a programme called the Deepam Scheme to subsidize the
cylinder deposit fee for women from households with incomes below the poverty line to
facilitate the switch from biomass to LPG. Such schemes will encourage the rural poor to
use cleaner fuels. The use of solar energy for cooking is also recommended.
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3. Modification in Stove Design
Use of cleaner fuels should be the long-term goal for the intervention. Till this goal is
achieved, efforts should be made to modify the stoves to make them fuel efficient and
provide them with a mechanism (eg chimney) to remove pollutants from the indoor
environment. Several designs of such stoves have been produced. NIOH study
showed significant decrease in levels of SPM, SO2, NOx and formaldehyde with
specially designed smokeless stoves in comparison with traditional cooking stoves.
However, they have not been accepted widely. Large scale acceptance of improved
stoves would require determined efforts. The most important barriers to new stove
introduction are not technical but social.
4. Improvement in Ventilation
In many parts of the country poor rural folk are provided with subsidized houses
under various government/international agencies aided schemes. Ventilation in the
kitchen should be given due priority in the design of the houses. In existing houses,
measures such as putting a window above the cooking stove and providing cross
ventilation through the door may help in diluting the pollution load.
5. Multisectoral Approach
Effective tackling of indoor air pollution requires collaboration and commitment
between agencies responsible for health, energy, environment, housing and rural
development.
8. National Programme on Improved Chulhas (NPIC):
The Indian government initiated the NPIC in 1983 in response to concerns about
deforestation and rural fuel poverty. The NPIC was implemented by the Ministry of
Non-conventional Energy Sources (MNES) in cooperation with regional, district, and
state government offices. Under the original program, the NPIC provided a subsidy of
at least 50% for households purchasing an improved cook stove.
Objectives of this programme are: (i) fuelwood conservation; (ii) removal/reduction
of smoke from kitchens; (iii) reduction of deforestation and environmental
degradation; (iv) reduction in the drudgery of tasks performed by women and girlchildren and their consequent exposure to health hazards; and (v) employment
generation in rural areas.
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NPIC follows a multi-model, multi-agency approach. Annual targets, in terms of the
number of chulhas to be installed, are determined at the national level and are then
disaggregated at the state level to be implemented by nodal departments.
From 1983 to 2000, approximately 35 million ICS of various types were distributed;
however, the NPIC has not been effective or successful over the long term in
promoting a fundamental change-over to improved stoves in India. In 2002 the NPIC
was deemed a failure and funding was discontinued; responsibility for continued ICS
dissemination was passed to the states.
9 National Biomass Cook stoves Programme(NBCP)
•
NBCP has been proposed for implementation during the 12th Plan Period with
strategy to expand development and deployment of cookstoves in the country.
•
It has provision for demonstration of 24.0 lakh improved biomass cookstoves for
household applications and 3.5 lakh cookstoves for community cooking applications.
•
The objective is to replace the existing traditional chullhas by improved biomass cook
stoves for domestic and community cooking, hence to save fuel and address health
hazard concerns due to inefficient combustion of Biomass in traditional chullhas.
•
The community cookstoves will be deployed in Mid-Day-Meal Scheme in
government schools, Aaganwadis, Tribal Hostels, Forest Rest-Houses, Dhabas and
Restaurants on national highways, etc. The programme is under consideration for
approval.
Objectives:
1. To develop and deploy improved biomass cook-stoves for providing cleaner
cooking energy solutions in rural, semi-urban and urban areas using biomass as
fuel for cooking.
2. To mitigate drudgery and address health related concerns of women and
children using traditional chulha for cooking.
3. To mitigate climate change by reducing the carbon and other emissions
resulting from burning biomass for cooking.
Activities
23
1.
2.
3.
4.
5.
6.
7.
8.
To support R&D activities on development of efficient and cost effective
designs of biomass cook-stoves with reduced emissions.
To provide support for Test Centres for carrying out performance testing of
biomass cook-stoves as per BIS.
Development of revised test protocols and standards.
To take up a series of pilot scale projects using existing commercially
available and better cookstoves and different grades of process biomass fuel
with ultimate aim exploring a range of technologies deployment biomass
processing and delivery models leveraging public-private partnerships.
Supporting training to manpower facilitating operation and maintenance
networks at local level thus generating opportunities for employment.
Taking up dissemination programme on improved family type and large
size cook-stoves for cooking applications.
Awareness for use of biomass cookstove in target groups.
The field and market experience of the above pilot project will be analyzed
for developing a business model for commercialization including availing
CDM benefit for biomass cookstove.
Target Users
•
To promote replacement of the existing in-efficient traditional chulhas in households,
kitchen of Mid-day Meal (MDM) scheme schools & Aangwadi and small business
establishments (road side dhabas, small hotels and restaurants and a variety of cottage
industries like textile dyeing, drying of spices etc.) with highly fuel efficient biomass
improved cookstoves.
•
To improve the indoor air quality in rural kitchen/households and health conditions
of the
•
To enhance the performance and competitiveness workmen employed in small
businesses of small businesses by achieving savings in firewood and food hygiene.
•
To build the capacity of local masons and fabricators in the design and construction
of energy-efficient stoves with the aim of creating new livelihood/ employment
opportunities.
•
To arrest large scale deforestation by substantial reduction of biomass use in small
business.
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References:
1. ICMR Bulletin on indoor air pollution in india – a major environmental and public
health concern. Vol.31, No.5 May, 2001
2.
Indoor air pollution in developing countries: a major environmental and public health
challenge. Bulletin of the World Health Organization, 2000, 78 (9)
3. Air Quality Guidelines Global Update 2005 WHO Regional Office for Europe
4. K. R. Smith. Indoor air pollution in developing countries: recommendations for
research
5. Junfeng (Jim) Zhang and Kirk R Smith Indoor air pollution: a global health concern.
British Medical Bulletin 2003; 68: 209–225.
6. Indoor air pollution from solid fuels and risk of low birth weight and stillbirth. WHO
7. The health effects of indoor air pollution exposure in developing countries. World
Health Organization, Protection of the Human Environment Geneva 2002.
8. Kalpana Balakrishnan et al Indoor Air Pollution Associated with Household Fuel Use
in India. An exposure assessment and modeling exercise in rural districts of Andhra
Pradesh, India
9. R.D. Hanbar and Priyadarshini Karve. National Programme on Improved Chulha
(NPIC) of the Government of India: an overview. Energy for Sustainable
Development l Volume VI No. 2 l June 2002.
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