Animal feedlots in Australia, and to a greater extent, concentrated animal feeding operations (CAFOs) worldwide, impact both the local and global environment as well as the health of the surrounding communities – in addition to the horrifying conditions for the animals therein.
One of the biggest hazards of raising large numbers of animals for consumption is the enormous quantity of waste they produce. For example, in the United States alone, the Environmental Protection Agency (EPA) has estimated that animals raised for food produce 3 to 20 times the amount of waste as the entire country’s human population.
While animal manure has benefits in terms of providing nutrients to crops, in large quantities it becomes extraordinarily harmful. Animal waste contains pathogens and antibiotics, which can run off and contaminate groundwater and surface water. When drinking water sources are contaminated, illness and death can result – particularly in infants, young children, older adults, and those with compromised immunity.
Runoff can also alter the natural biochemistry of surface water sources like rivers and lagoons, disrupting the ecosystem and having devastating impacts on aquatic life. For example, algal blooms can occur due to excess nitrogen or phosphorus in the water, which can secrete toxins into the water or block sunlight from entering the water. This can destroy other aquatic animals such as turtles and fish, and create dead zones that are depleted of oxygen and unable to sustain most aquatic life.
Residents who are local to animal feedlots also experience hazardous exposures to chemicals and airborne particulate matter, just as slaughterhouse workers do. Feedlots create airborne particulate matter such as fur, feathers, and dry excrement, and the presence of vast quantities of manure create chemical hazards including ammonia and hydrogen sulfide. These chemical and particulate hazards have significant harmful effects on air quality. Children are disproportionately affected by poor air quality, and it has been found that those living near animal feedlots (within a 5 kilometre radius) are at higher risk of developing asthma or other respiratory and immunological problems.
There are also indirect impacts of reduced air quality such as inability to spend time outdoors or even to allow fresh air into homes, reducing quality of life and wellbeing, and increasing mental distress.
The placement of animal feedlots disproportionately within low-income and/or predominately non-white communities. These communities experience the brunt of the health impacts of animal feedlots, while at the same time having inequitable access to support and healthcare. The presence of animal feedlots in these communities perpetuates racial and economic inequity and amounts to environmental racism.
The environmental impacts of animal feedlots are greater than than the local community, however. Animal farming is associated with methane and nitrous oxide emissions, which is intensified with improper storage and treatment. Methane and nitrous oxide are highly potent greenhouse gases that post significant threats to our global climate.
The use of antibiotics amongst animals raised for consumption is another major threat to public health. Antibiotics are often administered to combat disease amongst the vast numbers of animals kept in close proximity. However, since animals often incompletely digest antibiotics, they are excreted via manure and can contaminate water sources, including drinking water supplies. The excessive use of antibiotics has led to a proliferation of antibiotic-resistant bacteria and a reduction in the effectiveness of antibiotic treatment in humans, overall.
References
Barrett, J.R. (2006). Hogging the air: CAFO emissions reach into schools. Environmental Health Perspectives 114(4), A241.
Mirabelli, M.C., Wing, S., Marshall, S.W., & Wilcosky, T.C. (2006). Race, Poverty, and Potential Exposure of Middle-School Students to Air Emissions from Confined Swine Feeding Operations. Environ Health Perspect, 114(4), 591-596.