This guy's scary enough looking without knowing there's poison in his veins. Photographer: Mike Di Paola/Bloomberg

It might seem like cause for cheer that the U.S. Food and Drug Administration has ordered the withdrawal of most drugs containing arsenic fed to chickens, turkeys and hogs. After all, getting a well-known poison out of the food chain seems like just the sort of thing the agency should be doing.

Temper your enthusiasm: First, one of the four drugs banned will stay on the market and continue to be fed to turkeys. Equally disturbing, the FDA acted only after food-safety groups threatened to sue, and almost four years after the agency was presented with a petition asking that arsenic-based drugs be withdrawn right away. The makers of the drugs were actually ahead of the FDA: They had voluntarily pulled three of them from the U.S. market a couple of years ago.

Why arsenic was even in animal feed in the first place is fairly shocking, though perhaps not so much given how industrial farms raise much of the food we eat. Since the 1940s, farmers have fed arsenic to animals as a way to promote growth and weight gain with less feed. Arsenic apparently helps fight some diseases and aids in tissue and vascular development, making the muscle of animals look more appealing to consumers. Historically, about 70 percent of the poultry raised in the U.S. has been fed arsenic-based drugs.

Although the type of arsenic fed to animals may not itself be a carcinogen, after being consumed it gets converted into a form that the scientific evidence suggests is. This is part of what finally persuaded the FDA to act.

Just as troubling as evidence that trace arsenic might be in the meat we eat is what happens to the toxin once it is passed through as animal waste. Some of the waste is used as fertilizer, or isn't properly disposed of, leading to arsenic in soil, water and crops.

Things get worse. The FDA's arsenic foot-dragging practically looks like a sprint compared with how the agency has responded to demands that it force farmers to stop the routine overuse of antibiotics in farm-animal feed. In the early and mid-1970s, amid signs that some bacteria were becoming resistant to antibiotics, the FDA decided to order a phase-out of penicillin and tetracycline for certain uses. These drugs, like arsenic, are used to promote animal weight gain.
Instead of following through and enforcing its own decision, the FDA bowed to pressure from Congress and drugmakers and did nothing for 35 years. Source and more...

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