The Food and Drug Administration (FDA) released its long-awaited antibiotic milk residue study in March, confirming the U.S. milk supply is safe.
“More than 99% of the samples are free of drug residues of concern, underscoring the safety of the U.S. milk supply,” according to the FDA release. The study sampled milk from nearly 2,000 dairy farms in 2012 and found drug residues that exceeded tolerance or safe levels on just 15 farms. One farm tested positive for two drugs. The total rate of violation was 0.7%.
“This report proves that America’s dairy farmers are delivering on our commitment to provide safe and wholesome milk to consumers, while working closely with state and federal regulators to continually improve the safety of our products,” says Jim Mulhern, National Milk Producer Federation (NMPF) president and CEO.
“Dairy farmers have a strong track record of compliance with state and federal milk safety regulations, and we support education and enforcement efforts to further strengthen that record,” he says. “These results are great, but we still are aiming for zero positives in the future.”
Of the 16 positive drug residues, 14 of those were for drugs that have no established tolerance or safe level. So any presence of any of those drugs above one part per billion is a violation. One of those drugs, Florfenicol, accounted for 10 of the 16 violative milk residues. In addition to Florfenicol, violative residues were found for Ciprofloxacin (1), Sulfamethazine (1), Tilmicosin (1), Tulathromycin (2) and Gentamicin (1).
FDA collected milk samples from 1,912 farms in 2012. FDA developed a targeted list of 953 farms that had previous meat tissue residue violations. It sampled another 959 “control” farms that did not have previous tissue violations. The targeted list of farms accounted for 11 of the residue violations; the control farms, four. Statistically, however, the rate of violations was not different between the two groups.
“Because the samples [in the FDA study] were collected in a blinded fashion, the FDA could not use positive
sample results to initiate enforcement action,” according to the release. Samples were tested for 31 drug residues that are not currently included in Grade A, Pasteurized Milk Ordinance (PMO) testing requirements. The PMO requires testing for Beta-lactam drugs. Every tanker load of milk is screened for those prior to its entry into the food supply.
Note: In fiscal year 2014, there were 3.14 million tanker loads of milk sampled for beta lactams, with 429 loads testing positive—a violation rate of 0.014%. The 17.75 million pounds of milk in these positive loads was discarded and did not enter the food supply. The screening also does not include the testing FDA does on retail-ready dairy products, notes NMPF: “The FDA conducts approximately 40,000 separate antibiotic residue tests of retail-ready dairy products annually, and has detected zero positives in the past four years.”