Producers who keep good records and have a definite sequencing, flushing and cleaning plan have far less sulfa carryover into the finishing feed than those without the plan. Generally, if the producer uses granular products at the approved level and has a conscientious sequencing, flushing and cleaning program, cross-contamination is not a problem. Compliance and enforcement Producers found in violation of regulatory standards for sulfa residue face serious disruptions in their production and marketing activities. The USDA Food Safety and Inspection Service is responsible for enforcing sulfa residue regulations. The service assures meat is safe and wholesome and condemns meat with violative drug residues.
Prosecutions can occur for producers who misuse sulfa or other medications.
USDA meat inspectors randomly sample pork carcasses at each slaughter plant for sulfa and other drug and chemical residues. If they find violative levels of sulfa, they notify the producer and a marketing embargo is placed on the farm until a sample of five hogs is tested and found to be free of sulfa residues. This can result in marketing delay of two to three weeks. The USDA is currently developing screening tests for use on the farm, at buying stations or in the plant. With the possibility of increased checking and testing for sulfa residues, producers may want to look at some of the new on-farm testing producers that are becoming available.