Evidence of Safety of Long-Term, High, Oral Doses of DDT for Man

Abstract

Twenty-four volunteers ingested technical or p,p′-DDT at rates up to 35 mg per man per day for 21.5 months. They were then observed for an additional 25.5 months, and 16 were followed up for five years. Storage of DDT and DDE and excretion of DDA were proportional to dosage. The fat of those receiving technical insecticide at the highest rate contained 105 to 619 ppm of DDT when feeding stopped. The average dosage of p,p′-DDT administered in this study was 555 times the average intake of all DDT-related compounds by 19-year-old men in the general population and 1,250 times their intake of p,p′-DDT. Since no definite clinical or laboratory evidence of injury by DDT was found in this study, these factors indicate a high degree of safety of DDT for the general population.