A federal court ruled Thursday that government regulators must, at long last, conclude whether feeding antibiotics to healthy livestock -- a widespread practice in factory farming designed to promote animal growth and prevent disease -- could pose a threat to human health. And if so, they must end the practice.

The U.S. Food and Drug Administration has failed to act for more than three decades on scientific evidence, including some of its own findings, showing that the indiscriminate use of antibiotics in animal feed can lead to the growth and spread of drug-resistant bacteria capable of infecting people.

Such infections, known as “superbugs,” kill 70,000 Americans in U.S. hospitals each year. (See “You Want Superbugs With That?”)

Ruling on a lawsuit brought last year by the Natural Resources Defense Council (which publishes OnEarth) and several partners, U.S. District Court Judge Theodore Katz said the FDA can no longer delay acting on its own 1977 safety findings and must determine whether there is a need to ban what’s known as the subtherapeutic use of antibiotics in livestock.

The FDA had previously approved use of the antibiotics in the 1950s, then started proceedings to withdraw that approval after its 1977 findings. But the agency failed to finalize the order due to pressure from drug companies, agribusiness, and their allies in Congress.

The judge stopped short of ordering the FDA to ban the practice Thursday and said drug sponsors should still have an opportunity to demonstrate that the subtherapeutic use of penicillin and tetracyclines is safe. He ordered the FDA commissioner to set a hearing on the issue.

As OnEarth has previously reported, fully 80 percent of the antibiotics used in the U.S. are given to livestock, and the vast majority are administered to promote growth and stave off potential infections, not to treat illness. Bacteria in the guts of farm animals can evolve to resist those antibiotics, then spread from livestock to the humans who tend them. Drug-resistant bacteria can then be passed on to people who have never been anywhere near a chicken house or hog barn.

Yet even as evidence of the practice’s negative impact on human health has grown, more drugs are being administered to livestock than ever before -- from 17.8 million pounds per year in 1999 to 29.8 million pounds in 2009.

Read OnEarth’s previous coverage of the antibiotics case from award-winning food writer Barry Estabrook, and look for more about this story soon on our Food, Health & Home channel.

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