Antibiotics are used in commercial fuel ethanol production facilities to control bacterial contamination. The FDA’s Center for Veterinary Medicine (CVM) has taken steps to determine the impact of the use of antibiotics in commercial fuel ethanol production facilities because ethanol co-products, primary distiller’s grains, are used as animal feed ingredients.
The Division of Animal Feeds within CVM issued a field assignment during fiscal year 2010 to survey distiller’s products for antimicrobial residues. A total of 46 samples were collected by FDA investigators and these samples were sent to FDA laboratories for analysis. These 46 samples consisted of 18 domestic-import samples (samples were in domestic commerce in the U.S. when collected, but the country of origin was outside the U.S.) and 28 domestic samples (samples were in domestic commerce in the U.S. when collected and the country of origin was the U.S.).
FDA laboratories analyzed the 46 samples for residues of up to 12 antibiotics (ampicillin, penicillin G, chlortetracycline, oxytetracycline, tetracycline, clarithromycin, erythromycin, streptomycin, virginiamycin M1, bacitracin A, chloramphenicol, tylosin) and monensin using the method found in Laboratory Information Bulletin (LIB) 4438.
Although, five of the 46 samples collected were initially reported as positive for antibiotics (above the limit of quantitation [LOQ] of the method) by the FDA laboratories, upon further evaluation of the analytical worksheets one sample was found to have a level of virginiamycin M1 that was below the LOQ verified by the laboratory and thus was no longer considered to contain antibiotics. The limit of quantification using the LIB 4438 method is 0.1 ppm for Virginiamycin M1, 0.5 ppm for erythromycin, and 1.0 ppm for penicillin.
Consequently, FDA/CVM’s final analysis finds that 4 of the 46 samples were quantifiable in the laboratory for antibiotics. The four positive samples contained a total of five antibiotic residues. Of the four positive samples, three were domestic samples and one was domestic-import sample. The results of the three positive domestic samples are detailed below. Virginiamycin M1 was detected at ~0.16 mg/kg (parts per million or ppm) on a dry weight basis in one sample. Erythromycin was detected at ~0.58 ppm on a dry weight basis in another sample. The final positive domestic sample contained virginiamycin M1 at ~0.15 ppm on a dry weight basis and penicillin G at ~0.24 ppm on a dry weight basis. Although the amount of penicillin found (0.24 ppm) is lower than the LOQ for penicillin, the laboratory was able to accurately quantify this sample for penicillin below 1 ppm.
Thursday April 12, 2012/ FDA/ United states.