A dairy cow from a farm near Petaluma, CA was sold for slaughter as food with antibiotic levels in its edible tissues high enough to consider the meat adulterated.

The U.S. Food and Drug Administration (FDA) advised Neil McIsaac & Son Inc, owner of the dairy farm, of the problem in a Sept. 9 warning letter.  

FDA said it found the dairy offered an animal for slaughter that was adulterated because it contained an unsafe animal drug.  The agency said a food can be found adulterated or impure if it is “held under insanitary conditions whereby it may be injurious to health.”

Patients are increasingly showing resistance to commonly used antibiotics and some fear animal drug residue getting into meat is a factor contributing to this problem.

Last April 21, the dairy sold the cow, identified by an ear tag, and the USDA’s Food Safety and Inspection Service (FSIS) subsequently took tissue samples from the animal and subjected them to testing.

FSIS analysis of the issue samples “identified the presence of penicillin in the kidney at 0.55 parts per million (ppm).”  The FDA tolerance level for penicillin in uncooked edible tissues of cattle is 0.05 ppm.

“The presence of this drug in the edible tissue from this animal in this amount causes the food to be adulterated…” the warning letter said.

“Our investigation also found that you hold animals under conditions that are so inadequate that medicated animals bearing potentially harmful drug residues are likely to enter the food supply,” FDA added.  It said the dairy’s treatment records were in poor shape.

FDA said the California dairy adulterated the new animal drug Penicillin G Procaine by using it in ways not listed on the approved label.  It ignored the “withdrawal period” called for on the label to cut off doses to animals that are shortly bound for slaughter.

The dairy also did not follow the “frequency of treatment” called for on the label, and did not rely on a licensed veterinarian as required for off-the-label uses.

FDA’s San Francisco district asked the dairy farm to respond to the warning letter within 15 business days.