Metabolism and Storage of DDT in Beef Cattle

Abstract

Abstract Beef steers were fed forage contaminated with technical DDT for 83 days. Fat samples were removed by omentectomy at various intervals after feeding of the contaminated forage had ceased. Residues of p,p′-DDE, DDD, and p,p′-DDT were found. DDD residues declined at the greatest rate, p,p′-DDT declined at an intermediate rate, while p,p′-DDE declined at the slowest rate. In a second experiment technical DDT was administered orally, intraperitoneally, and intravenously to beef steers. Fat samples were removed by omentectomy 3 days after dosing. The steers that received technical DDT intraperitoneally and intravenously stored DDD and p,p′-DDT in the fat at a much lower ratio than the orally treated animals. p,p′-DDT was administered by the oral, intraperitoneal, and intravenous routes in another experiment. Three and 8 days after dosing, the residues in the omental fat of the orally treated animals showed increased DDD to p,p′-DDT ratios when compared to these ratios for the other 2 groups which had declined from pre-treatment levels. The data suggest that p,p′-DDT is dechlorinated to DDD in the rumen of the bovine.