A class of antibiotics, banned in 2005, continues to show up in poultry products, suggesting they may still be in use against federal regulations, new research suggests.
A joint investigation by food scientists at the Johns Hopkins Bloomberg School of Public Health and Arizona State University found evidence that fluoroquinolones — used to treat serious bacterial infections in people -- were found in 8 of 12 samples of “feather meal,” a byproduct of poultry production made from feathers.
The findings, published in the journal Environmental Science & Technology, came as a surprise to researchers, who noted fluoroquinolone use in U.S. poultry production was banned by the U.S. Food and Drug Administration seven years ago. FDA instituted the ban as a result of an alarming increase in drug-resistant Campylobacter bacteria, which can cause foodborne illnesses.
"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 Love, lead author of the report. "The public health community has long been frustrated with the unwillingness of FDA to effectively address what antibiotics are fed to food animals."
Study co-author Keeve Nachman, of Johns Hopkins, said the findings may explain “why high rates of fluoroquinolone-resistant Campylobacter continue to be found on commercial poultry meat products over half a decade after the ban."
The study, which involved samples from six states and China, is the first to examine feather meal to determine what drugs poultry may have received prior to their slaughter and sale.
The annual per capita human consumption of poultry products is approximately 100 pounds – more than any other animal- or vegetable-derived protein in the U.S. Each year, the poultry industry raises nearly 9 billion broiler chickens and 80 million turkeys, according to the U.S. Department of Agriculture. Antibiotics are introduced into the feed and water of poultry to make them grow faster.
The industry also processes poultry feathers into feather meal, often added as a supplement to poultry, pig, and fish feeds or sold as an "organic" fertilizer.
In a companion study, researchers also found inorganic arsenic in feather meal used in retail fertilizers.
In conducting the study, researchers tested feather meal samples for 59 pharmaceuticals and personal care products. All 12 samples tested had between two and 10 antibiotic residues. In addition, seven personal care products -- including the pain reliever acetaminophen (the active ingredient in Tylenol), the antihistamine diphenhydramine (in Benadryl) and the antidepressant fluoxetine (in Prozac) were detected. Researchers also found caffeine in 10 of 12 feather meal samples.
"We strongly believe that the FDA should monitor what drugs are going into animal feed," urged Nachman. "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."