Decorative Image: man in laboratory

Durham-Humphrey Amendment of 1951

required human drugs which cannot be safely used without medical supervision must be dispensed only on the prescription of a licensed practitioner, and must bear the Rx legend

Delaney Clause - Food Additives Amendment of 1958 had an impact too, Following hearings in the early 1950s under Representative James Delaney, a series of laws addressing pesticide residues (1954), food additives (1958), and color additives (1960) gave the FDA much tighter control over the growing list of chemicals entering the food supply, putting the onus on manufacturers to establish their safety. Since drugs used in animal feed were also considered additives they were subject to the provisions of the food additive petition process.

The Delaney Clause prohibiting carcinogenic food additives was modified by the DES proviso in 1962, named for diethylstilbestrol, a hormone used against miscarriages in humans and to promote growth in food-producing animals. The proviso permitted the use of possible carcinogens in such animals as long as residues of the product did not remain in edible tissues.

Text Only Version Graphic Version Handout Version