Environmental Issues: Food and Agriculture
Playing Chicken with Antibiotics
Previously Undisclosed FDA Documents Show Antibiotic Feed Additives Don't Meet the Agency's Own Safety Standards
- The FDA has failed to act on its own findings about 30 reviewed antibiotic feed additives, part of a larger pattern of delay and inaction in tackling livestock drug use that goes back four decades.
- Scientists have demonstrated that nontherapeutic use of antibiotics to raise livestock promotes drug-resistant bacteria that can migrate from livestock facilities and threaten public health.
- The FDA should complete the decades-delayed process for withdrawing approval of penicillin and tetracyclines in animal feed.
Between 2001 and 2010, the United States Food and Drug Administration (FDA) quietly reviewed the safety of 30 penicillin and tetracycline antibiotic feed additives approved for "nontherapeutic use". Nontherapeutic use refers to using antibiotics for growth promotion or to prevent disease in typically crowded, often unsanitary conditions in livestock and poultry. NRDC obtained the previously undisclosed review documents from the FDA as a result of a Freedom of Information Act (FOIA) request to the agency and subsequent litigation made necessary by FDA's failure to provide any of the requested documents.
FDA's scientific reviewers' findings show that none of these products would likely be approvable as new additives for nontherapeutic livestock use if submitted today, under current FDA guidelines. Eighteen of the 30 reviewed feed additives were deemed to pose a "high risk" of exposing humans to antibiotic-resistant bacteria through the food supply, based on the information available. The remainder lacked adequate data for the reviewers to make any determination and their safety remains unproven. In addition, FDA concluded in their review that at least 26 of the reviewed feed additives do not satisfy even the safety standards set by FDA in 1973.
To our knowledge, FDA has taken no action since the reviews to revoke approvals for any of these antibiotic feed additives (although two were voluntarily withdrawn by the drug manufacturer). The FDA does not disclose sales of specific animal drug products, and we have no information about the quantities of these specific antibiotic additives that were sold for livestock use or administered to food animals. However, we found evidence suggesting that at least nine of these additives are being marketed today, and all but the two voluntarily withdrawn additives remain approved for use today.
Antibiotic overuse is a known and growing problem
The significance of these findings extends far beyond the 30 antibiotic feed additives reviewed. FDA data indicate that the types of antibiotics in the reviewed additives -- tetracyclines and penicillins -- together make up nearly half of all the antibiotics used in animal agriculture. Other feed additives with these same antibiotics, including generics, that are approved for similar uses would likely pose a similar risk of promoting antibiotic resistance. This risk was recognized by FDA in 1977 when it proposed to withdraw approvals for animal feed additives containing penicillin and most tetracyclines.
Furthermore, the use of tetracyclines and penicillins in animal feed is part of a larger problem of antibiotic overuse. Approximately 70 percent of all sales of medically important antibiotics in the United States are for livestock use. Scientists have demonstrated that nontherapeutic use of antibiotics to raise livestock promotes drug-resistant bacteria that can migrate from livestock facilities and threaten public health. These bacteria can spread resistant traits to other bacteria, and some of these shared traits also can confer resistance to antibiotics used primarily in human medicine.
Action must be taken to protect public health
Unfortunately, the FDA's failure to act on its own findings about the 30 reviewed antibiotic feed additives is part of a larger pattern of delay and inaction in tackling livestock drug use that goes back four decades. A recent voluntary policy adopted by FDA, "Guidance #213," recognizes the problem, but lacks meaningful requirements and seems unlikely to curb uses of the antibiotics reviewed here or any of the other problematic uses (for a number of reasons discussed further in the issue brief). It is time for decisive action to help protect the public from the threat of antibiotic resistance. The FDA should:
- Complete the decades-delayed process for withdrawing approval of penicillin and tetracyclines in animal feed, strictly limiting their use to treating sick animals and, in rare circumstances, to controlling disease outbreaks.
- Initiate the process for withdrawing approval for all other classes of medically important antibiotics approved for nontherapeutic livestock use that are not shown to be safe.
In the face of the FDA's continued inaction, Congress, food industry leaders, and consumers should step in to demand change. Congress should insist on real regulation of livestock antibiotic use as outlined in the Preservation of Antibiotics for Medical Treatment Act (PAMTA) in the House of Representatives and the Preventing Antibiotic Resistance Act (PARA) in the Senate. In the meantime, large food companies and consumers can reduce livestock antibiotic use by choosing meat and poultry supplied by producers that promote antibiotic stewardship in the livestock and poultry industry.
last revised 1/27/2014