Results of the study were published March 21 in Environmental Science & Technology. The study, conducted by the Bloomberg School’s Centre for a Liveable Future and Arizona State’s Biodesign Institute, looked for drugs and other residues in feather meal, a common additive to chicken, swine, cattle and fish feed. The most important drugs found in the study were fluoroquinolones, a broad spectrum of antibiotics used to treat serious bacterial infections in people, particularly those that have become resistant to older antibiotic classes. The banned drugs were found in eight of 12 samples of feather meal in a multistate study. The findings were a surprise to scientists because fluoroquinolone use in US poultry production was banned by the Food and Drug Administration in 2005. This is the first time investigators have examined feather meal, a byproduct of poultry production made from poultry feathers, to determine what drugs poultry may have received prior to their slaughter and sale.