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ILO Fact Sheet

Intensive Livestock Operations and Your Health

What is an Intensive Livestock Operation?

An Intensive Livestock Operation (ILO) [1] is characterized by three features: the number of animals, the industrial structure and high volume efficiency. The effect that ILOs have on the health of both rural and urban residents alike emerge from two major sources that characterize them; the excessive production of liquefied manure, and the use of subtherapeutic antibiotics.

Manure Odour

Manure from ILOs is liquefied as part of the barn cleaning process is kept in open-air lagoons until it is spread onto fields, typically corn growing in monoculture. The odour emitted by an intensive hog operation is not only an inconvenience, forcing rural residents to keep their windows shut. Living beside an ILO limits families’ ability to have company over, causes their and their children’s clothes to stink and limits the individuals’ autonomy over their own life. Manure isn’t only smelly; it is a source of over 400 volatile organic compounds.[2] Nearby residents are more prone to:

  • respiratory illnesses;
  • aggravated asthma particularly due to the dust from the operation;
  • damage to lungs;
  • be carriers for viruses;
  • sore throat;
  • headaches;
  • depression, feelings of hopelessness and helplessness; and
  • a loss of quality of life.

The problem of odour, and the threat to health is increased as liquid manure is spread onto fields releasing 150 gases including hydrogen sulphide, carbon dioxide, and methane. [3] Aside from the nuisance of odour, this system carries many serious risks including:

  • The release of noxious gases
  • The seepage of manure from the lagoon into the soil
  • Spillage during transport of manure, or overfilling of the lagoon
  • Runoff of manure on fields due to extensive applications


Workers at ILOs experience many of the same health effects as neighbouring residents. The workers at ILOs, however, work inside the barn where air quality is at its worst. Barn workers tend to be healthy adults, but they are subjected to an array of hazards such as respiratory infections, sprains, bruises, severe head trauma, fractures, electrocution and repetitive motion injury. In addition, physicians suspect that many health problems go unreported. Workers may fear lost wages or an unsympathetic supervisor. In other cases, people quit the job and do not complain.

One of the most indicative issues of Intensive Livestock Operations is the high worker turnover rate. High annual turnover rates result in a disproportionate number of workers at or near beginning wage rates. Considering the combination of concentrated ownership, the negative health consequences and high turnover rate; there is a theoretical loss of opportunity experienced by the worker. In a different day in age perhaps the worker could have owned their own small scale family farm and likely would not have a chronic respiratory disease.


Freshwater resources are FINITE and should be protected. Manure spills and runoff from over application and cracking lagoons threaten this resource. This is a daily concern for rural citizens, as to whether their well water contains dangerous levels of pathogens, heavy metals, or nitrates. High levels of nitrates in liquid manure has poses a threat to the future generation of rural residents. When excessive nitrates are consumed in contaminated water, they increase the risk of blue baby syndrome as well as miscarriages.[4]


ILO operators give the hogs a daily dose of antibiotics at levels below those recommended for illness, in other words a subtherapeutic dose, either in feed or water.

  • Urban and rural residents are exposed to anti-biotics through the meat they eat and the water they drink.

  • The antibiotics given to hogs are extremely similar to those prescribed to humans, indeed eleven antibiotics routinely administered to hogs are identical to those given to humans, including tetracyclines and penicillin.

  • We have seen increased levels of bacteria resistance to antibiotics in recent decades.

  • Individuals that possess allergies to specific antibiotics can risk exposure when consuming food products that contain these drugs.[5]

  • Bacteria that have developed resistance are able to transfer the DNA that conveys resistance to other species of bacteria, leading to increases in antibiotic resistant bacteria in humans.

What Can You Do?

  • Write a letter to your MP, to the Minister of Agriculture, and to the Prime Minister, demanding a ban on the use of sub-therapeutic levels of antibiotics on farm animals;

  • Write your provincial MPP (or MLA), the provincial Environment, Agriculture and Health Ministers and demand a moratorium be placed on the expansion of ILOs until long-term scientific research investigating the health effects of ILOs has been completed;

  • Contact the mayor and city council of your municipality to express your concerns. Encourage them to pass an anti-ILO declaration for their community and pass a by-law banning the construction of mega-hog barns; and

  • Be a responsible consumer – if that means that you boycott Maple Leaf and Smithfields, only buy pork from small farms, don’t eat pork, or buy organic pork – feel good about it.


    [1] The term ILO, in the context of this fact sheet, is designates the intensive production of hogs.

    [2] Halverson, Marlene, The Price We Pay For Corporate Hogs, Institute for Agriculture and Trade Policy, March 2001 (Second Printing), p. 61.

    [3] Hasselback, Paul, ”Intensive Livestock Operations and Health Problems”, Encompass, Vol.2, No.2,
    December 1997.

    [4] US Centers for Disease Control. Spontaneous Abortions Possibly Related to Ingestion of Nitrate: Contaminated Well Water in LaGrange County, Indiana 1991-1994. Morbidity and Mortality Weekly Report, Vol. 45, No. 26 July 5, 1996. Intensive Livestock Production.

    [5] Adkinson, N. Franklin. 1980. Appendix J: Immunological Consequences of Antimicrobials in Animal Feeds, in: The Effects on Human Health of Subtheraputic use of Antimicrobials in Animal Feeds. Washington D.C.: National Academy of Sciences


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