“The longer we use these drugs, the less effective the arsenal becomes,” said Margaret Mellon, a senior scientist at the Union of Concerned Scientists, which filed the complaint in federal court with the Natural Resources Defense Council, the Center for Science in the Public Interest, Food Animals Concern Trust and Public Citizen.
About 80 percent of the antibiotics used in the United States are consumed by farm animals.
Groups including the American Medical Association and the Infectious Diseases Society of America have called on the FDA to ban feeding antibiotics to healthy animals.
Rep. Louise M. Slaughter (D-N.Y.), the only microbiologist in Congress, has filed legislation that would ban the use of seven anitbiotic classes unless animals or herds are ill, or drug companies can prove their use does not harm human health.
“We should be able to buy our food without worrying that eating it will expose our families to bacteria no longer responsive to medical treatments,” she said.
Debate has raged for at least 30 years about using antibiotics in animal feed. The drugs have been used agriculturally since the 1950s to speed animal growth, prevent illness and treat unhealthy animals. Amid rising concerns, the FDA began questioning whether they should be used so broadly.
Agricultural interests oppose limits, saying there is no scientific proof that farm animals are the problem.
“Anti-modern livestock-production groups are trying to compel the FDA to ban antibiotics used to prevent animals from getting sick because those groups have a belief — not scientific evidence — that such FDA-approved animal health products are causing antibiotic resistance in people,” said Doug Wolf, a pork producer from Lancaster, Wis., and president of the National Pork Producers Council.
As farming has become more industrialized, farmers have relied more heavily on antibiotics because they help animals digest more efficiently and stay healthy in crowded conditions.
Meanwhile, the prevalence of antibiotic-resistant bacteria has increased. Resistant bacteria can evolve whenever drugs are used against them because substrains that are less susceptible to antibiotics will survive and multiply.
Scientists say that overuse of antibiotics in humans is a significant source of the problem but that there is growing circumstantial and genetic evidence that antibiotics given to animals are compounding the threat.
Last year, the FDA issued voluntary guidance to farmers, calling the resistant-bacteria problem a“public health issue of some urgency.” An FDA spokeswoman said Wednesday that the agency was reviewing public comments it had received.
Mellon said the agency is “trying to jawbone the industry into voluntarily giving up these drugs. I don’t know how they would get the industry to act in that way, because it’s against their interests.”