DERMAL ABSORPTION OF THE PHENOXY HERBICIDES 2,4-D, 2,4-D AMINE, 2,4-D ISOOCYTL, AND 2,4,5-T IN RABBITS, RATS, RHESUS-MONKEYS, AND HUMANS - A CROSS SPECIES COMPARISON

Dermal absorption of the 14C-ring-labeled phenoxy herbicides 2, 4-D ¡(2, 4- dichlorophenoxy)acetic add], 2, 4-D amine (2, 4-dichlorophenoxyacetic add dimethyl- amine), 2, 4-D isooctyl (2, 4-dichlorophenoxyacetic add isooctyl ester), and 2, 4, 5-T amine (2, 4, 5-trichlorophenoxyacetic acid trimethylamine) was examined following topical applications of the herbicides to the back of rabbits, the back and tail of rats, the forearm and forehead of rhesus monkeys, and the forehead of human volunteers. The effect of three pesticide vehicles (water, acetone, and Esteron LV96) was also investigated. The total percent dermal absorption was calculated from the mean percent urinary recoveries from the animal tests and corrected for nonurinary excretion of the radiolabel using data from intramuscular (im) injections. The human data are reported without im correction. The reliability of animal data for modelling human dermal absorption of pesticides is highlighted. © 1975 Taylor & Francis Group, LLC.