PERCUTANEOUS-ABSORPTION OF THE INSECTICIDES FENITROTHION AND AMINOCARB IN RATS AND MONKEYS

The dermal penetration of 14C-ring-labeled fenitrothion and aminocarb was determined in rats and rhesus monkeys. In monkeys, 49 .+-. 4% (t1/2 = 14 h) of the fenitrothion and 74 .+-. 4% (t1/2 = 25 h) of aminocarb were absorbed from the forehead, while 21 .+-. 10% (t1/2 = 17 h) fenitrothion and 37 .+-. 14% (t1/2 = 31 h) aminocarb were absorbed from ventral forearm. Monkey forehead was 2.3 times and 2.0 times more permeable than the forearm for fenitrothion and aminocarb, respectively. In rats, 84 .+-. 12% (t1/2 = 20 h) of the fenitrothion and 88 .+-. 6% (t1/2 = 17 h) aminocarb was absorbed from the middorsal region. These results were corrected for incomplete excretion by intramuscular injections of fenitrothion in money, 95 .+-. 7% (t1/2 = 12 h), and rat, 69 .+-. 9% (t1/2 = 12 h), and aminocarb in monkey, 95 .+-. 14% (t1/2 = 8 h), and rat, 63 .+-. 6% (t1/2 = 15 h). These results suggest rapid dermal absorption of these pesticides in rats and monkeys and the use of these animal models for measuring dermal penetration is discussed.