The use of manure that allegedly contains livestock antibiotics and its impact on human health and the environment
Petition: No. 276
Issue(s): Agriculture, human health/environmental health, and science and technology
Petitioner(s): Frank Woodcock
Date Received: 23 April 2009
Status: Completed
Summary: The petitioner is concerned about the potential health impact of ingesting food crops that accumulate antibiotics from soils spread with livestock manure. The petitioner asks the federal government if it is aware of this situation and what it is doing to protect Canadians from involuntarily ingesting antibiotics from food crops, such as vegetables, that are grown with livestock manure.
Federal Departments Responsible for Reply: Agriculture and Agri-Food Canada, Health Canada, Public Health Agency of Canada
PetitionFrank Woodcock
35 Tyrell St.
Simcoe, ON
N3Y 2H2
April 20, 2008The Auditor General of Canada
Commissioner of the Environment and Sustainable Development
240 Sparks St.
Ottawa, ON
K1A 0G6
Attn. Petitions.
Please accept the following petition under the Auditor General Act.[Information withheld]
Sources:
http://jeq.scijournals.org/cgi/content/abstract/37/3/1245[Information withheld]
Source:
http://www.sciam.com/article.cfm?id=vegetables-contain-antibioticsIt seems the government of Canada allows vegetables containing antibiotics to be consumed by Canadians. This is not economically, scientifically, environmentally, biologically, morally or ethically sustainable.
Question 1: Was the Canadian government previously aware vegetables could upload antibiotics?
Question 2: Considering humans pass antibiotics to the sewer system and to our water system; it is logical to assume animals pass antibiotics to manure piles, spread on the same ground used to grow vegetables. Why was the Canadian government not aware vegetables could upload antibiotics?
Question 3: Considering some toxic bacteria have become antibiotic immune, what is the effect on Canadians regularly ingesting vegetables containing antibiotics?
Question 4: What can the Canadian government do to protect Canadians from ingesting antibiotics they do not wish to ingest?
Question 5: How does the value of an acre of farmland containing antibiotics compare to an acre without antibiotics?
Question 6: Is farmland containing antibiotics sustainable?
[Original signed by Frank Woodcock]
Frank Woodcock
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Minister’s Response: Agriculture and Agri-Food Canada1 September 2009
Mr. Frank Woodcock
35 Tyrell Street
Simcoe, Ontario N3Y 2H2Dear Mr. Woodcock:
I am writing in response to Environmental Petition No. 276, which you submitted pursuant to section 22 of the Auditor General Act. On 7 May 2009, the office of the Commissioner of the Environment and Sustainable Development forwarded the petition to the Honourable Leona Aglukkaq, Minister of Health, and me for response. Our departments will be responding separately.
In your petition, you posed six questions, two of which relate to my portfolio. Enclosed, please find Agriculture and Agri-Food Canada’s response to questions five and six of your petition.
Thank you for your interest in this important matter.
Sincerely,
[Original signed by Gerry Ritz, Minister of Agriculture and Agri-Food and Minister for the Canadian Wheat Board]
Gerry Ritz, PC, MP
Enclosure
c.c.: Mr. Scott Vaughan
Commissioner of the Environment and Sustainable DevelopmentThe Honourable Leona Aglukkaq, PC, MP
Government of Canada’s Response to
Environmental Petition No. 276 filed by Frank Woodcock
under Section 22 of the Auditor General Act
Received 23 April 2009Petition asking for a response to questions
on the impact of livestock antibiotics on the environment14 August 2009
Agriculture and Agri-Food Canada
Environmental Petition 276
Agriculture and Agri-Food Canada Response to Petition 276—Reply to the petitioner’s questions on the impact of livestock antibiotics on environment. AAFC to respond to questions 5 and 6.
Question 5: How does the value of an acre of farmland containing antibiotics compare to an acre without antibiotics?
There is no measure AAFC is aware of comparing the economic value of an acre of land that contains antibiotics with one that does not. Soils naturally contain a wide diversity and abundance of antibiotic-producing and antibiotic-resistant microorganisms. Against this background, the impact of small amounts of antibiotics of anthropogenic origin is likely small. Certainly AAFC is not aware of any evidence suggesting that the productivity of land that has been treated with manure from medicated animals is lower than that of land that has not. It is not a normal practice to analyze land for the types and amounts of antibiotics present, or to include this analysis in the valuation of the property.
Question 6: Is farmland containing antibiotics sustainable?
It is normal farming practice to manure soils for the benefit of soil quality and crop yield. These manures can contain minute traces of antibiotics depending on what the animals received, and how the manure was treated prior to application. Antibiotics will be broken down in the soil over time. Some antibiotics will be rapidly degraded, others somewhat more slowly. But overall, there is no evidence that antibiotics will accumulate in the soil.
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Joint Response: Health Canada, Public Health Agency of Canada3 September 2009
Mr. Frank Woodcock
35 Tyrell Street
Simcoe, Ontario N3Y 2H2Dear Mr. Woodcock:
This is in response to your environmental petition no. 276 of April 20, 2009, addressed to Mr. Scott Vaughan, the Commissioner of the Environment and Sustainable Development (CESD).
In your petition you raised questions about the impact of livestock antibiotics on the environment.
I am pleased to provide you with the enclosed Health Canada response to your petition. I understand that the Minister of Agriculture and Agri-Food will respond separately to questions that come under the purview of his department.
I appreciate your interest in this important matter, and I hope that you will find this information useful.
Sincerely,
[Original signed by Leona Aglukkaq, Minister of Health Canada]
Leona Aglukkaq
Enclosure
c.c.: Mr. Scott Vaughan, CESD
The Honourable Gerry Ritz, P.C., M.P.Health Canada Response to
Environmental Petition No. 276 filed by Frank Woodcock
under Section 22 of the Auditor General Act
Received May 7, 2009Petition asking for a response to questions
on the impact of livestock antibiotics on the environmentSeptember 4, 2009
Minister of Health
Health Canada Response to Petition 276 – Reply to the Petitioner’s questions on the impact of livestock antibiotics on the environment.
Question 1: Was the Canadian government previously aware vegetables could upload antibiotics?
The Canadian government regularly reviews or pays attention to the literature reports related to veterinary antibiotic residues in food products. As such, we are aware of literature reports that have shown the detection of antibiotic drug residues in vegetables, e.g. the articles mentioned in the petition and published in Journal of Environmental Quality 2005;34(6); 2007;36(4); and 2008;37(3). We do understand the importance of these published studies, which provide scientific evidence on how to more appropriately address the issues associated with veterinary antibiotic residues. From these specific studies, however, it is noted that the antibiotic residue levels (e.g. chlortetracycline and sulfamethazine), when detected, were very low. These levels are lower than the maximum residue limits currently established for the edible tissues (meat) of food animals or lower than the acceptable daily intakes established by the Joint FAO/WHO Expert Committee on Food Additives. Nevertheless, together with its stakeholders, the Canadian government has been consistently promoting the prudent use of veterinary antimicrobials to minimize the veterinary drug residues in food products/environments and to limit the development of antibiotic resistance in bacteria of public health concern.
The above mentioned literature reports also provided evidence that the on-farm manure management practices such as composting and stockpiling constitute an effective way in further inactivating certain antibiotic residues, thereby preventing or minimizing potential residues that are uploaded to vegetables from manure-amended soil.
It is noted that the literature on antibiotic residues in vegetables to date is still very limited but does warrant more research. We continuously review literature reports and further assess the implications of the vegetable antibiotic residues in public health. When necessary, appropriate actions will be taken to continue to effectively protect the health of Canadians.
Question 2: Considering humans pass antibiotics to the sewer system and to our water system, it is logical to assume animals pass antibiotics to manure piles, spread on the same ground used to grow vegetables. Why was the Canadian government not aware vegetables could upload antibiotics?
Animals are given veterinary antibiotic drugs for treatment, control and prevention of infectious diseases as well as in some situations for increasing feed efficiency and growth promotion purpose. The administrated drugs and/or their metabolites in animals are mainly excreted via feces or urine and enter the manure piles. However, the on-farm manure management practices such as composting and stockpiling will likely further inactivate the drug residues remaining in manures before their land application. As indicated in the response to Question 1 above, we are aware of literature that shows detection of antibiotic drug residues in vegetables at levels below the maximum residue limits and will continue to monitor and assess relevant new literature and its implications.
Question 3: Considering some toxic bacteria have become antibiotic immune, what is the effect on Canadians regularly ingesting vegetables containing antibiotics?
Antibiotic resistance is a global public health issue and associated with the use of antibiotics in either human or veterinary medicine. The Canadian government considers managing antibiotic resistance a key priority and continues its effort to address it at both the national and international levels. The sale of antimicrobial drugs in veterinary medicine is authorized by Health Canada’s Veterinary Drugs Directorate (VDD). The human safety evaluation of veterinary antimicrobials in Canada has routinely included the microbiological safety assessment which mainly includes antimicrobial resistance risk assessment. A key issue is to minimize or contain the development and spread of antibiotic resistance in food animals. The labels of veterinary antimicrobial products in Canada, when necessary, include warning statements on antibiotic resistance. Accordingly, the labels of certain previously approved antimicrobial products have been requested to include additional warning statements related to antibiotic resistance. For example, the warning statements on the labels may specify that to limit the development of antibiotic resistance, the antibiotics should only be used to treat individual cases of disease, and not used in mass medication or in an extra-label manner. All of these measures by Health Canada are to protect human health and the safety of Canada’s food supply.
More specific to the question, “the effect on Canadians ingesting vegetables containing antibiotics”, it is considered that there is not likely to be an effect of antibiotic residues from vegetables on the development of bacterial antibiotic resistance in consumers, since the residue levels detected to date in vegetables have been very low from the viewpoint of antibiotic resistance development.
Question 4: What can the Canadian government do to protect from ingesting antibiotics they do not wish to ingest?
Health Canada has a rigorous drug approval process in place to protect human and animal health, and the safety of the food supply. A comprehensive human safety assessment is conducted before a veterinary antibiotic drug is approved for sale for use in food animals in Canada. The assessment includes the establishment of a maximum residue limit for that particular drug entity in edible tissues of that animal (i.e., meat, milk, eggs and honey) which is a level that can be safely consumed by humans over a life time if that particular food product is consumed everyday (i.e., acceptable daily intakes as mentioned in the response to Question 1 above). There is considerable safety margin taken into account while setting these maximum residue limits in foods of animal origin (meat, milk, eggs and honey).
References
1. Chander Y, Kumar K, Goyal SM, Gupta SC. 2005. Antibacterial activity of soil-bound antibiotics. Journal of Environmental Quality. 34(6):1952-7.
2. Dolliver H, Kumar K, Gupta S. 2007. Sulfamethazine uptake by plants from manure-amended soil. Journal of Environmental Quality. 36(4):1224-30.
3. Dolliver H, Gupta S. 2008a. Antibiotic losses in leaching and surface runoff from manure-amended agricultural land. Journal of Environmental Quality. 37(3):1227-37.
4. Dolliver HA, Gupta SC. 2008b. Antibiotic losses from unprotected manure stockpiles. Journal of Environmental Quality. 37(3):1238-44.
5. Dolliver H, Gupta S, Noll S. 2008c. Antibiotic degradation during manure composting. Journal of Environmental Quality. 37(3):1245-53.
6. Dolliver H, Kumar K, Gupta S, Singh A. 2008d. Application of enzyme-linked immunosorbent assay analysis for determination of monensin in environmental samples. Journal of Environmental Quality. 37(3):1220-6.
7. Health Canada. 2002. Report of the Advisory Committee on Animal Uses of Antimicrobials and Impact on Resistance and Human Health. Available at: http://www.hc-sc.gc.ca/dhp-mps/pubs/vet/amr-ram_final_report-rapport_06-27_cp-pc-eng.php . Last accessed on July 28, 2009.
8. Health Canada Veterinary Drugs Directorate. 2008. Administrative maximum residue limits and maximum residue limits set by Canada. Available at: http://www.hc-sc.gc.ca/dhp-mps/vet/mrl-lmr/mrl-lmr_versus_new-nouveau-eng.php.Last accessed on June 12, 2009.
9. Joint FAO/WHO Expert Committee on Food Additives. 2001. Summary of evaluations performed by the Joint FAO/WHO Expert Committee on Food Additives (sulfamethazine), November 12, 2001. Available at:
http://jecfa.ilsi.org/evaluation.cfm?chemical=SULFADIMIDINE&keyword=SULFAMETHAZINE. Last accessed on June 12, 2009.
10. Joint FAO/WHO Expert Committee on Food Additives. 2003. Summary of evaluations performed by the Joint FAO/WHO Expert Committee on Food Additives (chlortetracycline, oxytetracycline and tetracycline),
January 30, 2003. Available at: http://www.inchem.org/documents/jecfa/jeceval/jec_409.htm. Last accessed on June 12, 2009.
11. Kumar K, Gupta SC, Baidoo SK, Chander Y, Rosen CJ. 2005. Antibiotic uptake by plants from soil fertilized with animal manure. Journal of Environmental Quality. 34(6):2082-5.
