Environmental Fate
Plant/Surface Water. Several transformation products reported by Day (1991) include
4-amino-m-tolyl-N-methylcarbamate (AA), 4-amino-3-methylphenol (AC), 4-formamidom-tolyl-N-methylcarbamate (FA), N-(4-hydroxy-2-methylphenyl)-N-methylformamide
(FC), 4-methylformamido-m-tolyl-N-methylcarbamate (MFA), 4-methylamino-m-tolyl-Nmethylcarbamate (MAA), 3-methyl-4-(methylamino)phenyl-N-methylcarbamate (MAC),
phenol, methylamine and carbon dioxide. MAA was not detected in natural water but was
detected in fish tissues following exposure to aminocarb-treated water in the laboratory.
The metabolites FA, AC and MAC were detected in Canadian forests treated with aminocarb but the metabolites AA, MAA and FC were not detected (Day, 1991)
On and/or in bean plants, aminocarb degrades with the carbamate moiety remaining
intact. Methylcarbamate derivatives identified include the 4-methylamino, 4-amino, 4-
methylformamido and 4-formamido analogs (Abdel-Wahab et al., 1966)
Photolytic. When aminocarb in ethanol was irradiated by UV light, extensive degradation was observed. No degradation products were identified; however, two unidentified
cholinesterase inhibitors were reported (Crosby et al., 1965).
Chemical/Physical. Aminocarb is hydrolyzed in purified water to 4-(dimethylamino)-
3-methylphenol which is then converted to 2-methyl-1,4-benzoquinone. This compound
was then oxidized to form the following compounds: 6-(dimethylamino)-2-methyl-1,4-
benzoquinone, 6-(methylamino)-2-methyl-1,4-benzoquinone, 5-(dimethylamino)-2-
methyl-1,4-benzoquinone and 5-(methylamino)-2-methyl-1,4-benzoquinone (Leger and
Mallet, 1988). When aminocarb was irradiated by a high pressure xenon-mercury lamp
(λ = 253.7 nm) in aerated and degassed ethyl alcohol and cyclohexene solutions, 4-
dimethylamino-3-methyl phenol formed as the major product. A duplicate run using an
excitation wavelength of >300 nm yielded that same phenol as the major product. Sinceaminocarb absorbs radiation in the solar region (at λ >300 nm), this compound would be
expected to undergo photochemical degradation in the environment (Addison et al., 1974)
Emits toxic fumes of nitrogen oxides when heated to decomposition (Sax and Lewis,
1987)
Metabolic pathway
Aminocarb in purified water is hydrolyzed to 4-
(dimethylamino)-3-methylphenol which is in turn
converted to 2-methyl-1,4-benzoquinone either by
direct means or via 2-methyl-1,4-dihydroquinone. The
benzoquinone reacts readily with methylamine and
diethylamine present in solution to give four red
chemicals. In addition, mono- and diepoxides of
2-methyl-1,4-benzoquinone are formed.
