Reasons for increased scrutiny of
animal agriculture
• Increasing population that is more aware
• Increasing per capita consumption
– Processed foods
– Meat
• Larger facilities
Consequences
• More potential for environmental
problems
– More waste in one place
• More opportunity for utilization and
management
– Economies of scale
– Scale of operation
Environmental concerns
• Non-point source pollutants
– Definition
– Categories
•
•
•
•
•
•
•
Sediment*
Nutrients*
Pesticides
Salts
Metals
Bacteria*
Sulfates
Yellow denotes that agriculture is
a source
* Denotes that animal ag is a
source
Nutrients
• N
• P
• Organic Matter
N and water quality
• Groundwater concern
Ammonia
Ammonia
fertilizer
(Denitrification)
Assimilation
Ammonification
N and water quality
• Methemoglobinemia – “Blue baby
syndrome”
P and water quality
• Surface water concern
• Eutrophication of surface water
– Natural aging process; nutrient enrichment;
high plant and algae growth; organic matter
accumulation
Eutrophication
• Definition – high productivity
• Symptoms
– Frequent algal blooms; reduced variety of
algae; blue-green predominant species; shift
in fish populations (pelagic rather than
benthic), anoxia or near anoxia
• Limiting nutrients – N but usually P
– 0.3 – 3.0 mg/L total P
Eutrophication
• Sources
–
–
–
–
–
–
Rainfall (N and P)
Runoff (N and P)
Sewage and decomposition (N and P)
Atmospheric fixation (N)
Waterfowl (N and P)
Groundwater (N)
Eutrophication
• Consequences
– Algae decomposition products – affect taste,
odor, color
– Weeds – clogging treatment filters
– Increased color and turbidity
– Anoxia – release of H2S, redox sensitive
minerals
– Aesthetics
Organic matter concerns
• Primarily, surface water
– Fishkills
• DNR statistics
– Hypoxia
• stats
– Pfisteria
• Human effects
100
80
157 water sources in
Iowa were classified
as impaired
60
40
20
Impairment
Other
Nitrates
Pesticides
Turbidity
Algae
Organic enr.
Fecal Coliform
Flow alt.
Nutrients
0
Silt
Number of water sources
Impairments to Iowa's water sources
(1998)
Issues associated with grazing
– Sedimentation and turbidity
• Overgrazing of riparian vegetation
– Stream channelization
• Overgrazing of riparian vegetation
– Nutrient impairment and algae growth
• Pasture runoff
– Bacterial contamination
• Pasture runoff
Annual Sediment, P, and N loading of Rock Creek Lake
from tributaries with different proportions of
pastureland (Downing et al., 2000)
Sediment
Total P
Total N
6.0
5.0
60
50
4.0
40
3.0
30
2.0
20
1.0
10
0
Watershed 1
10
15
20
2
25
3
30
35
40
Pasture, % of total land
45
P and N, kg/ha
Sediment, MT/ha
70
Air Quality Regulations and
Activity
• 1997 Clean Air Act Amendments
– National Ambient Air Quality Standards
(NAAQS)
• Primary pollutant standards
• Secondary pollutant standards
NAAQS
6 criteria pollutants
•
•
•
•
•
CO
Pb
SO2
O3
Particulate matter
– PM10
– also PM2.5
• NO2
Particulate Matter
• Primary pollutant
– respiratory health
– livestock sources include feed dust,
secondary formation (fugitive)
• Secondary pollutant
– visibility (haze)
– livestock sources include feedlot dust, road
and tillage dust (fugitive)
Feedlot dust control - timed
irrigation
Fugitive dust
• EPA estimates that 50% of PM2.5
emissions arise from fugitive dust sources
Ammonia + nitric acid
or sulfuric acid
From fields,
feedlots, manure
storage, housing
Ammonium
Nitrate or
Ammonium
sulfate
Sources of ammonia
4%
5%
3%
2%
On-Road and NonRoad Engines and
Vehicles - 5%
All Other - 4%
Chemical & Allied
Product Mfg. - 3%
Waste Disposal &
Recycling - 2%
86%
Misc. (includes
livestock and
fertilizer) - 86%
National Ambient Air Quality
Standards (1997)
• Ozone
– new standard- 0.8 ppm avg over 8 hr vs. 0.12
ppm avg over 1 hr
– results primarily from nitrogen oxides and
VOCs
– regulation of fuels and motor vehicles will
have some impact on agriculture
– reducing concentrations should result in
improved yield
Other air quality areas
• Secondary pollutants
– Odor
– Greenhouse gases (CH4, CO2, N2O)
• Equivalency of different gases
Ruminant animal
Waste systems
Rice production
Natural gas
Coal extraction
Biomass burning
Tg-CH4/yr
100
Anthropogenic sources of CH4
(70% of total production)
80
60
40
20
0
Ruminant animal
Waste systems
Rice production
Natural gas
Coal extraction
100
Biomass burning
Tg-CH4/yr
Greenhouse Gases
Anthropogenic sources of CH4
(70% of total production)
80
60
40
20
0
Iowa Greenhouse Gas Action
Plan
• Control emissions from animal
agriculture
• Balance the production of GHG with
carbon sequestration capacity
Iowa Greenhouse Gas Action
Plan
• 1 hog generates the same GHG
equivalents as 2.5 humans
• Must cover all CAFO manure storages
• Need to curtail N2O emissions from
CAFOs
• New approaches to reducing methane
Odor
• 200+ compounds
• Interaction of compounds
• Health effects???
Nuisance pollutants
• Noise
• Flies
Safety
• Depletion of oxygen
• Poisonous gases
• Explosions
Other issues
• Disease transmission
• Insects and rodents
• Visual aesthetics
Air Quality Concerns
• From the neighbor’s perspective, shift
more towards human health concerns
rather than nuisance
Iowa Concentrated Animal
Feeding Operations Air Quality
Study
• Released February 8, 2002
• Responded to 5 questions from the IDNR
regarding human health impacts from
AFOs
– Recommended exposure levels for emissions
of concern
Recommendations
H2S
• H2S - not exceed 70 parts per billion (ppb) for a
1-hour time-weighted average (TWA) period,
measured at the CAFO property line.
• The concentration at a residence or public use
area shall not exceed 15 ppb.
• Each CAFO should be provided up to seven
days each calendar year when they are allowed
to exceed the concentration for hydrogen
sulfide
Recommendations
NH3
• NH3 - not to exceed 500 ppb for a 1-hour TWA
period, measured at the CAFO property line
• The concentration at a residence or public use
area shall not exceed 150 ppb
• Each CAFO should have up to seven days each
calendar year when they are allowed to exceed
the concentration for ammonia.
Recommendations
Odor
• No consensus reached on odor. Therefore
two opinions provided.
– 7:1 dilutions at the residence; 15:1 at the
property line
– No data to support recommendations of odor
concentration in relation to human health
Iowa SF2293
• Rules completed by the end of August 2002
• Anticipated regulations for NH3 and H2S will
be developed
• Unique – health-based therefore, measures will
be at the residence
• IDNR to conduct an 18-month monitoring
study (regulation)
Current status of SF2293
• Maximum 1-hr average H2S
concentration not to exceed 15 ppb at the
separated distance
• Maximum 1-hr average NH3
concentration not to exceed 150 ppb at
the separated distance
• No odor standard
Odor Regulations
• Missouri
– Requires development of odor control plans
– 5.4:1 odor threshold limit at the property line
• Enforcement is currently on hold
• Minnesota
– H2S, as an odor indicator
• 30 ppb, 30-min average, twice in five d
• 50 ppb, 30-min average, twice annually
– Currently considering a health-based, residence
standard
Odor Regulations
• Colorado
– 15:1 dilution threshold standard for nonswine uses
– Housed commercial swine feeding operations
• 7:1 at the property line
• 2:1 at the residence
Additional Activity
• California
– In response to non-attainment of PM10 and
ozone standards
• VOC and PM10 emission reductions of 30% and
47%, respectively, by 2006
• 50% NH3 emission reduction from dairy by 2006
• Idaho
– Very early stages of implementing VOC
standards for CAFOs that are health-based
Emerging Environmental Issues
• Bioaerosols
• Endotoxin
• Pathogens
• Antibiotic resistance
• Endocrine disruptors
• Mortality management
• http://www.state.ia.us/government/dnr/organiz
a/epd/wastewtr/feedlot/faq.htm
Emerging issues are not
nutrient issues
• May require a non-traditional solutions
– Will need non-traditional expertise to
address
Antibiotic resistance
• Zahn et al., 2001 (JAS 79(Suppl 1):783)
• Aerial transfer of tylosin and TRB from swine
finishers
– 3 mechanically-ventilated facilities
– 20 g*ton-1
• 8.1 ± 5.3 ng*L-1 tylosin exhausted
• TRB represented 80% of culturable bacteria
• Under year-round average ventilation rates,
exhausted tylosin concentration represents
30% of tylosin fed
Estrogens in the Environment
• 17B-estradiol and xenoestrogens are the most
offending
• Finlay-Moore et al., 2000. JEQ 29(5):1604
• No grazing effects on estradiol or testosterone
concentration in runoff
• Amendment with broiler litter increased runoff
concentrations of estradiol and testosterone 15fold
• Reproductive management solutions????