Occurrence of sulfa drug residues in canadian pork liver.

Sulfonamide residues in the livers of wholesome carcasses of Canadian pork were monitored over the six year period ending March 31, 1985. The annual rate of violative residues decreased from 9.92% to 2.75% over the course of the six years. At present the incidence of violation in the livers is 2.35% and there is no significant difference within the various regions of Canada. This would result in a muscle violative rate of 0.8%.The only sulfonamide found at violative levels was sulfamethazine. All violative samples were within the range 0.11-4.00 ppm. Over the period of the survey the incidence of violations at all levels decreased. Violations at higher levels decreased most rapidly resulting in a continuous reduction of the mean level in violative samples.