
Naniehg mer” and me cheee labeled carbaryl was administered to 
pigs, sheep, monkeys and two men. The major metabolite observed in urine 
were VI and VII. In addition to these two metabolites, small amounts of 
compound IX was observed with pigs; VIII and IX, with sheep, VIII, with 
monkeys; and IX and X with the men (1577). In studies on the effects of 
carbaryl on a work population, engaged in its manufacture, workers excreted 
both free and conjugated napthol in the urine (110). It was also shown 
that human liver converted carbaryl to l-naphthol and other water soluble 
compounds (944) After exposure of carbaryl to plasma of 15 different animals, 
l-naphthol was identified in each case (242). 
Rat livers were shown capable of degrading carbaryl to l-naphthol and 
water soluble metabolites (944). Using rat liver microsomes, carbaryl was 
degraded into six known compounds and at least as many unidentified materials. 
The methyl group was modified to give l-naphthyl-N-hydroxymethylcarbamate. 
Ring hydroxylation occurred to yield 4-hydroxy- and traces of 5-hydroxy-1l- 
naphthyl-N-methylcarbamate and 5,6-dihydroxy-5,6-dihydro-1-naphthy1-N- 
methylcarbamate. There was some evidence that the 3,4-dihydroxy-3,4-dihydro- 
analog was also formed. In addition to these materials, the hydrolysis 
product l-naphthol was also found. Water-soluble fractions, probably conju- 
gates of carbamates and their hydrolytic products, were obtained but not 
identified. These would be expected to consist of glucosiduronic acids, 
sulfates, mercapturic acids, N-acetylmercapturic acids and glucosides (378, 
: 379, 1111, 1112). 
Bean plants were injected with labeled carbaryl. Six days later the 
water soluble metabolites were recovered and treated with @—glucosidase. 
The following aglycones were recovered: 5,6-dihydroxy-5,6-dihydrocarbaryl, 
N-hydroxymethyl carbaryl, 4- and 5-hydroxycarbaryl, and l-naphthol (845, 
846). 
In cotton plants, carbaryl was readily absorbed by the root system. 
Hydrolytic and non-hydrolytic paths contributed almost equally to the 
metabolism of carbaryl. In the hydrolytic path, a specific carbamate 
esterase catalyzed the hydrolysis of the ester bond, liberating l-naphthol and 
N-methylcarbamic acid. The latter underwent spontaneous degradation to give 
up CO». A small portion (about 34) of the absorbed material was eliminated 
as a basic volatile material, probably unchanged amine. Using appropriately 
c!4-labeled carbaryl, it was shown that the methyl group underwent oxidation. 
For the non-hydrolytic path, there was evidence of oxidation of the intact 
carbaryl, probably to a hydroxylated metabolite (1045). 
Carbaryl persisted longer in soil water than in lake water. Four 
days after treatment of soil water, l-naphthol as well as carbaryl was 
recovered (872). 
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