Human/Animal Rights
Environmental Damage from Factory Farming of Animals
By author not identified.
May 26, 2008, 13:24

Environmental Damage (from factory farming of animals) Taken from: http://www.factoryfarm.org/?page_id=19

As a result of irresponsible management practices, inadequate regulation, and insufficient oversight, factory farms are among the worst polluters in the U.S. The fundamental problem: too much poop. Every animal needs to eat, drink, and eventually eliminate its waste (manure and urine). When thousands of animals are confined in one small area on a factory farm, the waste accumulates very quickly. For instance, every day, an average dairy cow produces about 21 times as much waste as an average human¹ - so a mega-dairy CAFO with 15,000 cows generates as much animal waste as a city of 315,000 people! But unlike cities, factory farms aren�ft required to install hi-tech sewage treatment facilities; instead, animal waste is stored in manure lagoons and periodically sprayed onto the surrounding land. This process spews toxins into the air, and can pollute surface water and groundwater, damaging the environment, killing aquatic organisms, and threatening human health.

Water Pollution

Water pollution is among the most devastating environmental impacts of factory farming. Pollutants from factory farms reach surface and ground water through manure lagoon spills, manure lagoon leaks, application of waste to farmland, runoff, and intentional waste releases. Pollutants can also be emitted into the air, and later be deposited in soil and surface water.

Manure Lagoons

Factory farms store manure in huge holding facilities called manure lagoons. Unfortunately, massive lagoon spills occur far too often. These spills can be caused by overflow after heavy rainfall, collapse of lagoon walls, mechanical failure in pumps, pipes, and other equipment, accidental releases, or intentional releases to drain waste from the lagoon.²

Large manure lagoon spills have a devastating impact on the environment; the sudden release of huge quantities of animal waste disrupts ecosystems, kills fish and other aquatic life, contaminates sources of drinking water, and makes waterways unsafe for recreational use.

In the News

In August 2005, a massive manure spill occurred at a dairy in western New York after a wall of its manure lagoon collapsed. As a result, three million gallons of animal waste spilled into the Black River, killing 200,000 to 250,000 fish, disrupting recreational tourism, and forcing Watertown, NY to temporarily suspend use of the river as a source of its public water supply.^{3, 4}

Leaky Lagoons

Water is also polluted when waste leaks out of manure lagoons. Although factory farm owners may claim that these structures are leak-proof, in reality, pollutants often seep out into the surrounding soil, eventually contaminating groundwater and/or surface water.⁵ In fact, a certain amount of lagoon leakage is allowed by law; for example, in Iowa, lagoons can leak up to 1/16�� of liquid waste per day. Over time, this releases a huge amount of pollution into the soil.

A number of factors can cause manure lagoons to leak; liners can be damaged by repetitive freezing-thawing, wetting/drying, weathering of outer walls, pressure from roots, and tunneling by rodents or worms.^{6, 7}

Application of Waste

Groundwater and surface water are also polluted when factory farms apply too much manure to the surrounding land. As described above, factory farms generate much more waste than the plants in the surrounding area can use. As a result, excess waste is applied to fields and can eventually be washed into surface water and groundwater by rainfall or melting snow.

Atmospheric Deposition

A process called volatilization causes ammonia from factory farm waste to be released into the atmosphere as a gas. Later, the ammonia can be deposited on the ground and/or into surface waters in a dry form, or dissolved in rain.⁸

Water Pollutants of Primary Concern

Nutrients:

Animal manure is rich in nutrients such as nitrogen and phosphorus, which, in small quantities, can improve soil quality and help plants to grow. In fact, before the era of industrial agriculture, farmers fertilized crops by spreading livestock manure throughout their fields. (Today, sustainable farmers continue to use this efficient farming technique.)

However, modern-day factory farms generate enormous quantities of waste that contain far more nutrients than plants in the surrounding fields are able to use. These excess nutrients can be carried into groundwater and surface water, causing serious damage to the natural environment.

According to the 1998 National Water Quality Inventory conducted by the EPA, 30% of surveyed rivers, 44% of surveyed lakes, and 23% of surveyed estuaries were contaminated with unsafe levels of nutrient pollution.⁹ Nitrogen and phosphorus pollution is also the primary source of damage to coastal waters in the U.S.; more than 60% of U.S. coastal rivers and bays are moderately or severely damaged by nutrient pollution.¹⁰

Eutrophication (Nutrient Over-Enrichment)

What is Eutrophication?

The process in which excess nutrients are added to a body of water, causing excessive plant growth, and ultimately reducing the amount of oxygen dissolved in the water.

When excess nutrients are added to surface waters, they can cause more algae to grow. This creates two problems; first, algae cloud the water and block sunlight, killing underwater plants which ordinarily provide food and shelter for fish and other aquatic life.¹¹ This leads to fish kills and the reduction of biodiversity.¹² The abundance of algae also ruins the visual appearance of streams, rivers, and lakes, and prevents them from being used for recreation.

In addition, the algae eventually die and are decomposed by bacteria - this process uses oxygen dissolved in the water, thus reducing the amount of oxygen available for fish, crabs, and other aquatic organisms. This causes fish kills, reduces biodiversity, and in extreme cases, can wipe out all aquatic life, creating �gdead zones.�h

The Dead Zone

Nutrient pollution has created an oxygen-depleted �gdead-zone�h in the Gulf of Mexico. This 7,700 square mile section of water (an area approximately the size of New Jersey), is now devoid of aquatic life.¹³

Harmful Algal Blooms

Eutrophication can also cause rapid growth of highly toxic species of algae. One notorious toxic alga, Pfiesteria piscicida, emits toxins thought to break down the skin tissue of fish, causing bleeding sores or lesions, and ultimately resulting in massive fish kills.^{14, 15} Exposure to Pfiesteria is also harmful to humans; the alga�fs potent toxins can cause neurological damage, memory loss, confusion, respiratory ailments, skin problems, and gastro-intestinal illness.^{16, 17} Numerous Pfiesteria outbreaks have occurred in the Chesapeake Bay and in the coastal waters of North Carolina, which are severely polluted with nutrients from animal manure.

For more information, visit the EPA�fs Pfiesteria piscicida webpage.

Contamination of Drinking Water:

As described in the human health section of this site, nutrient pollution from manure can also threaten public health by increasing nitrate levels in drinking water. Infants exposed to nitrate-contaminated drinking water can develop methemoglobinemia, or �gblue baby syndrome,�h a potentially fatal condition that reduces the blood�fs oxygen-carrying capacity.¹⁸ Although evidence is inconclusive, the EPA suspects that nitrate pollution can also cause additional human health disorders.¹⁹

According to the EPA, in U.S. counties with factory farms, approximately 1.3 million households rely on wells in which nitrate levels exceed the Maximum Contaminant Level.²⁰

Ammonia

Ammonia from animal waste poisons aquatic life and can cause additional damage to waterways by reducing the amount of dissolved oxygen in water. This decreases aquatic species diversity, and can lead to fish kills.²¹ Ammonia pollution also causes eutrophication, further reducing biodiversity and degrading aquatic ecosystems.

Pathogens

Pathogens are living microorganisms (such as bacteria, viruses, and parasites) that can cause disease, affecting both human and wildlife populations. Animal manure can carry a variety of harmful pathogens, including Campylobacter, E. coli, and Salmonella.

When waste from a factory farm enters ground or surface waters, pathogens can contaminate the water, making it unsafe for humans to drink, and in some cases, unsafe for swimming and other recreational uses.²² Pathogens can cause a range of symptoms including stomach cramps, vomiting, diarrhea, fever, kidney failure, and even death.^{23, 24} Since pathogens are able to attach to sediment and can be released back into water when a streambed is disturbed, this form of water pollution poses a long-term threat to human health.²⁵

Antibiotics

Factory farms administer huge quantities of antibiotics to livestock in order to promote growth and prevent widespread disease. Scientists estimate that 25 to 75% of all antibiotics pass into manure unchanged.²⁶ As a result, when waste from factory farms enters the environment, antibiotics can contaminate surface water and groundwater. This promotes the development of antibiotic-resistant bacteria, which makes antibiotics used for humans less effective.²⁷

Scientists have found that these antibiotic-resistant bacteria can be transported by surface water and groundwater;²⁸ A study in Ohio revealed that 67% of water samples taken near poultry factory farms contained antibiotics.²⁹

Hormones

Factory farms regularly administer hormones to beef cattle and dairy cows in order to boost growth rates or increase milk production. When hormones are injected into an animal, some of the hormones pass into its waste, and can eventually contaminate surface and groundwater.³⁰ Research demonstrates that hormone pollution can disrupt the development and reproductive systems of fish.³¹ Learn more on Sustainable Table�fs Hormones and rBGH pages.

Salts and Trace Elements:

Animal manure also contains salts (such as sodium, calcium, magnesium, potassium, chloride, sulfate, bicarbonate, carbonate, and nitrate) and elements (such as arsenic, copper, selenium, and zinc).³² When huge quantities of manure are concentrated in one area, these substances can accumulate and eventually be carried into groundwater and surface water.³³ This can make water unsuitable for drinking and can disrupt ecosystems by damaging soil, restricting plant growth, and harming wildlife.^{34, 35}

Organic Matter and Solids:

Waste from factory farms contains organic matter (biodegradable, carbon-based material that occurs naturally in animal manure). After organic matter enters surface waters, it�fs decomposed by bacteria and other microorganisms that use oxygen dissolved in the water.³⁶ As a result, less oxygen is available for organisms living in the water - this can cause fish kills and can reduce species diversity and overall life within the aquatic ecosystem.³⁷

Waste from factory farms may also contain various solid materials such as spilled feed, bedding materials, litter, and hair.³⁸ When these materials enter surface water, they can increase turbidity (cloudiness of the water), harming populations of fish, crabs and other aquatic organisms.³⁹

Air Pollution

Factory farms also damage the environment by releasing a host of harmful pollutants into the air. Emitted from confinement buildings, waste stored in manure lagoons, and from the land on which manure is spread or sprayed, the most significant air pollutants are hazardous gases derived from urine, manure, and the decomposition of these animal wastes, and particulates from feed, animals, and animal waste.⁴⁰

Air pollutants of primary concern:

Hydrogen Sulfide (H₂S)

This colorless, highly toxic gas is among the most dangerous pollutants emitted by factory farms. While exposure to high levels of hydrogen sulfide causes rapid loss of consciousness, shock, pulmonary edema, coma and death,⁴¹ exposure to very low concentrations - even levels well below the thresholds for irritation or toxicity - can also be harmful;⁴² studies have linked low levels of exposure to cough, throat irritation, eye symptoms, nasal symptoms, and headache.⁴³ Other reported symptoms include nausea, stomach distress, dizziness, and blistering of the lips.⁴⁴ Learn more in the Human Health Impact section.

Ammonia (NH₃)

In the U.S., approximately 80% of all anthropogenic (human-made) ammonia emissions are released by livestock manure.⁴⁵ When this pungent toxin is eventually deposited in rivers, streams, and coastal estuaries, it increases the amount of available nitrogen in the water, and thus contributes to eutrophication. Ammonia emissions can also degrade the environment by reducing atmospheric visibility, increasing soil acidity, and impairing ecosystem productivity.⁴⁶

Ammonia also damages human health; research suggests that exposure to moderate concentrations of ammonia can cause humans to develop severe cough and mucous production; higher concentrations can cause scarring of the upper and lower airways, reactive airways dysfunction syndrome, persistent airway hypersensitiveness, lower lung inflammation, and pulmonary edema.⁴⁷ Learn more in the Human Health Impact section.

Particulate Matter

Particulate matter is composed of large and small particles of various solids or liquids suspended in the air. Particulates emitted by factory farms may include fecal matter, feed materials, skin cells, and bioaerosols such as bacteria, fungi, spores, viruses, pollens, endotoxins, exotoxins, and products of microorganisms.⁴⁸

In addition to contributing to haze,⁴⁹ particulate matter can damage human health; research indicates that long-term exposure to dust particles from factory farms can lead to persistent respiratory symptoms and a decline in lung function.⁵⁰ Exposure to bioaerosols may induce asthma, cough, chest tightness, and hypersensitivity pneumonitis (�hfarmer�fs lung�h).⁵¹

Odor

The most obvious air pollutant emitted by factory farms is odor, which is comprised of a complex mixture of chemicals produced by bacteria as they break down food in animals�f digestive systems and manure that has been excreted.⁵² In one study, researchers identified 331 fixed gases and volatile organic compounds (VOCs) in samples of air emitted from factory farms in North Carolina.⁵³

In addition to drastically diminishing the quality of life of those living in the surrounding communities, odor from factory farms can adversely affect human health.⁵⁴ Exposure to odor from factory farms has been linked to headache, eye irritation, nausea, nasal irritation, diarrhea, hoarseness, sore throat, cough, chest tightness, nasal congestion, palpitations, shortness of breath, stress, drowsiness, and alteration in mood. ^{55, 56}

Greenhouse Gases

Globally, the livestock sector generates 18% of all anthropogenic greenhouse gas emissions measured in carbon dioxide equivalent.⁵⁷ This is due primarily to its emissions of the potent and persistent greenhouse gasses, methane and nitrous oxide, as well as its production of smaller quantities of carbon dioxide. Remarkably, the livestock sector produces 37% of the world�fs anthropogenic methane emissions and 65% of all anthropogenic nitrous oxide emissions.⁵⁸

Additional Environmental Damage

Overuse of Water

Factory farms use enormous quantities of water. In addition to providing drinking water for thousands of animals onsite, factory farms use this scarce resource to flush manure out of barns.⁵⁹ Industrial milking centers that utilize manure flush cleaning and automatic cow washing systems can use as much as 150 gallons of water per cow per day!⁶⁰

In many parts of the country, this excessive water use can deplete groundwater, leading to problems such as ground subsidence or water contamination due to saltwater intrusion.⁶¹ Water overuse is especially problematic in areas above the Ogallala Aquifer (the nation�fs largest aquifer), which is being depleted rapidly.

Increased Transportation

Since livestock production is concentrated on factory farms, which replaced the many small farms that once supplied meat and dairy products to surrounding communities, these foods must now be transported much longer distances before reaching consumers. This additional transportation causes increased emission of carbon dioxide, nitrous oxide, sulfur oxides, particulate matter, and other harmful air pollutants, which impairs human health and exacerbates environmental problems such as global climate change, acid rain, and the acidification of ecosystems. For more information, visit Sustainable Table�fs Fossil Fuel and Energy Use page.

Use of Animal Feed

Livestock raised on factory farms consume tremendous quantities of animal feed, much of which is produced from crops grown on large-scale farms that use huge quantities of synthetic fertilizers and pesticides. Heavy use of fertilizers contributes to the problem of nutrient pollution, which causes severe damage to waterways throughout the U.S., and releases substantial quantities of nitrous oxide, which contributes to global climate change.⁶² Toxic pesticides have also polluted waterways, disrupting aquatic ecosystems, and threatening human health. It should also be noted that feed must be transported to factory farms, thus creating additional air pollution as described above. For more information, visit Sustainable Table�fs Feed and Pesticides pages.

Future Outlook

It�fs obvious that the indiscriminate environmental damage caused by factory farms is irresponsible, unsustainable, and downright foolish. Fortunately, small traditional farms successfully produce delicious, nutritious foods without degrading the natural environment - they�fve been doing so for hundreds of years!

The secret? Spreading the waste. As noted above, manure is rich in nutrients that help plants grow. When sustainably raised animals graze on pasture, they�fre able to simultaneously fertilize the fields with their manure. Since plants absorb the nutrients from the manure, surface water and groundwater remain clean. Factory farms are unable to recycle animal waste in this manner; since industrial farms cram so many animals into one place, they generate much more manure than can ever be used by plants in the surrounding area.

Learn more about sustainable agriculture on the Sustainable Table website.

Find sources of sustainably raised foods in your area with the Eat Well Guide.

Facts:

• According to the 1998 National Water Quality Inventory, agricultural sources were responsible for 60% of the pollution in surveyed rivers and streams and 45% of the pollution in surveyed lakes.⁶³
• The EPA warns that �gbacteria and viruses such as E. Coli, salmonella and Giardia found in dairy waste can contaminate drinking water and cause acute gastroenteritis and fever, kidney failure, and even death.�h⁶⁴
• E. coli and other bacteria can survive in manure for several months.⁶⁵
• The EPA reports that the waste generated by hogs, chicken, and cattle has polluted over 35,000 miles of river and has contaminated groundwater in 17 states.⁶⁶

For More Information:

Concentrating on Clean Water: The Challenge of Concentrated Animal Feeding Operations. Executive Summary Full Report

Produced for the Iowa Policy Project, this comprehensive report provides an outstanding overview of the adverse impacts of factory farms on water quality.

EPA Eutrophication website

This EPA website includes basic background information about eutrophication, an environmental problem caused in part by nutrient pollution from factory farms.

Cesspools of Shame: How Factory Farm Lagoons and Sprayfields Threaten Environmental and Public Health

This NRDC report focuses on the human health hazards created by irresponsible waste disposal practices utilized on factory farms. The report includes detailed information about the health threats posed by water pollutants from factory farms.

How Sustainable Agriculture Can Address the Environmental and Human Health Harms of Industrial Agriculture

Written by researchers from the Center for a Livable Future at the Johns Hopkins Bloomberg School of Public Health, this article provides an excellent overview of the problems caused by factory farms. (Environmental Health Perspectives, May 2002)

Iowa Concentrated Animal Feeding Operation Air Quality Study

This study provides a thorough review of scientific research about air pollution generated by factory farms. The study provides detailed information about the impacts of air pollution on human health.

Livestock�fs Long Shadow: environmental issues and options

Prepared for the Food and Agriculture Organization of the United Nations, this comprehensive report provides a very detailed assessment of the many environmental impacts of livestock production.

1. This figure was calculated using dairy and human waste characteristics reported in the USDA�fs Agricultural Waste Management Field Handbook (1992),^a assuming an average lactating dairy cow weight of 1,400 lbs., and an average human weight of 175.8 lbs. The average human weight of 175.8 lbs. is a weighted average calculated using mean weights by sex and age group as reported by the CDC (Ogden et. al. 2004),^b and the 2005 population estimates by sex and five-year age groups released by the Population Division of the U.S. Census Bureau (2006).^c
   
   Waste Calculation:Weight of waste excreted by lactating dairy cow: 80.00 lbs./day/1,000 lbs. of live weight.^a (Weight of waste excreted by a 1,400 lb. lactating dairy cow: 112.0 lbs./day.) Weight of waste excreted by human: 30.00 lbs./day/1,000 lbs. of live weight.^a (Weight of waste excreted by a 175.8 lb. human: 5.274 lbs./day.) Thus a 1,400 lb. lactating cow excretes 21.24 times as much waste per day as a 175.8 lb. human.a. U.S. Department of Agriculture, Soil Conservation Service. Agricultural Waste Management Field Handbook. USDA. p. 4-8, 4-18. April, 1992.
   b. Ogden, Cynthia L., Cheryl D. Fryar, Margaret D. Carroll, Katherine M. Flegal. Mean Body Weight, Height, and Body Mass Index, United States 1960-2002. Advance Data from Vital Health Statistics. Vol. 347. p.1-20. October 2004.
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