Traces Of Banned Antibiotics Discovered In Poultry

The scientists said they detected fluoroquinolones, which are antibiotics used to treat a broad spectrum of bacterial infections in people, as well as other over-the-counter drugs and residues in feather meal, known as a common additive to livestock feed for chickens, pigs, cattle and fish.

The government, via the Food and Drug Administration, banned use of the antibiotics in the production of poultry seven years ago over rising concern about the spread of bacteria found to be resistant to antibiotics.

"The discovery of certain antibiotics in feather meal strongly suggests the continued use of these drugs, despite the ban put in place in 2005 by the FDA," said David C. Love, the study's lead author and a microbiologist with Bloomberg School's Center for a Livable Future. "The public health community has long been frustrated with the unwillingness of FDA to effectively address what antibiotics are fed to food animals."

Banned drugs still being fed to chickens

But researchers from the two schools, in a study published the journal Environmental Science & Technology, said they discovered the banned drugs in eight of twelve samples of feather meal they sampled from six states and China. They also found caffeine in 10 of the dozen samples.

"This study reveals yet another pathway of unwanted human exposure to a surprisingly broad spectrum of prescription and over-the-counter drugs," said study co-author Rolf Halden, PhD, PE, co-director of the Center for Health Information & Research, and associate director of the Swette Center for Environmental Biotechnology at Arizona State University.

"It's concerning to see that banned drugs are being fed to chickens," said Love. "They were banned for obvious health reasons."

Keeve Nachman, the study's co-author who is also from the Center for a Livable Future at Johns Hopkins, said the FDA outlawed fluoroquinolones in the production of poultry livestock because of what he described as an alarming rise in resistance among Campylobacter bacteria.

"With such a ban, you would expect a decline in resistance to these drugs," said Nachman, in a press release. He noted that continued use of the banned drugs and the resultant unintended contamination of the poultry feed could be the reason for high rates of resistant bacteria found on commercial poultry meat so many years following the government ban.

The study marks the first time researchers examined feather meal, which results in production of poultry and is made of feathers. The purpose of the study was to see what drugs birds received prior to being slaughtered and sold to consumers.

Love said feathers tend to collect more antibiotics than does bird meat.

Faulty sample? Sure…

Statistics show that about nine billion broiler chickens and 80 million turkeys are produced in the U.S. annually. Some one-third of each bird's total weight winds up being recycled into other products, including pet food, poultry feed and fertilizer. Feathers and bones alike are used to make the byproducts.

During the study, researchers exposed several strains of E. coli bacteria to the concentrations of antibiotics found in the feather meal samples. In doing so, they also discovered the drug residues could select for resistant bacteria.

"A high enough concentration was found in one of the samples to select for bacteria that are resistant to drugs important to treat infections in humans," Nachman said.

"We strongly believe that the FDA should monitor what drugs are going into animal feed," he continued. "Based on what we've learned, I'm concerned that the new FDA guidance documents, which call for voluntary action from industry, will be ineffectual."

In an email published by the Baltimore Sun, a spokesman for the National Chicken Council suggested that the banned antibiotics and other substances found in the feather meal were left over from past use of the products, or could even have come from cross-contamination following faulty sample collection.