Aminocarb degradation

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). 

See also Pheromone technology for typographus, 49-53 Air circulation, 175-88 See also Wind speed and aminocarb degradation, 218-24 Aircraft equipment, 80,82,85 95-99 atomizer and nozzle design, 99-115 Turbo Thrust aircraft and Jet Ranger helicopter, 123t... 

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). 

Leger, D.A. and Mallet, V.N. New degradation products and a pathway for the degradation of aminocarb [4-(dimethylamino)-3-methylphenyl IV-methylcarbamate] in purified water, J. Agric. Food Chem., 36(1) 185-189, 1988. 

In order to evaluate the potential hazards chemical insecticides pose to forest environments, it is essential that adequate and reliable research data be generated on their environmental chemistry (distribution, persistence, movement, metabolic degradation, toxicity, fate, etc.). This paper gives a brief account of some laboratory and field research activities carried out at the Forest Pest Management Institute, Canadian Forestry Service to meet this requirement. Using two chemical insecticides which are extensively used now in forest insect control programs in Canada Viz aminocarb [Trade name, Matacil 4-dimethylamino-m-tolyl N-methylcarbamate] and fenitrothion [0,0-dimethyl 0-(3-methyl-4-nitrophenyl) phosphorothioate], studies conducted at the Institute to elucidate the environmental behavior and fate of forestry insecticides in general will be discussed. 

Laboratory Studies on Insecticide Degradation. Degradation in natural waters Stream water (pH 6.0) and sediment (organic content 36%) were taken from a small shallow stream (depth ca 20 cm, width oa 1.5 m) in the Goulais River watershed, a mixed conifer-deciduous forest area, ca 50 km northeast of Sault Ste. Marie, Ont., Canada. Two degradation studies in duplicate (one for aminocarb and another for fenitrothion) were set up according to Sundaram and Szeto ( 1 ). Aminocarb and fenitrothion (100 pg/L in acetone) were added separately to 1000 mL aliquots of sterilized (Ameco Sterilizer 1 h) and unsterilized stream water in either open or closed 1500 mL Erlenmeyer flasks. The latter were sealed with polyethylene snap caps which were removed once a day for about 1 min. to allow air exchange. The flasks were incubated at 15 0.2°C in an environmental chamber. Unfortified water... 

Figure 1. Degradation of aminocarb in fortified natural and sterile stream water in open and closed flasks.

The rate constants (t l) and half-lives (t. ) for both autoclaved and non-autoclaved aminocarb and fenitrothion samples in open as well as closed flasks varied considerably (Figures 1 and 2). Rate constants were higher (more rapid degradation) in open flasks and half-lives were longer in closed flasks, showing that... 

Movement and degradation of aminocarb in water/sediment mode 1 The concentrations of aminocarb in water and sediment at different intervals during incubation are presented graphically in Figure 3. During the experimental period, the concentration of aminocarb in water in non-autoclaved flasks decreased from 92 (open) and 95 (closed) ppb to 11 and 21 ppb respectively, while... 

Figure 3. Movement and degradation of aminocarb in a water/sediment model.

Movement and degradation of fenitrothion in the water/sed-iment model The concentration of fenitrothion in non-autoclaved and autoclaved stream waters in the presence of sediment are shown in Figure 4. The concentration of fenitrothion decreased rapidly in water and increased rapidly in sediment, showing that fenitrothion has a greater tendency than aminocarb for translocation from water to sediment. Within 15 h, 94% (open flask) and 89% (closed flask) of the chemical in the non-autoclaved samples was lost from the aqueous phase and the corresponding concentrations in sediment were 43% and 66% respectively. The rapid translocation of this compound from water to sediment was probably due to its lipophilic nature (], ). Such a phenomenon was not very significant for aminocarb because it was present in water as a cationic species at pH 6.0. At the end of the experimental period (75 h), only 0.2% and 0.5% of the chemical remained in water whereas the sediments contained 19% and 31% of the fortified levels respectively. The rapid loss in the open flask is primarily attributable to volatilization coupled with some microbial degradation. In the absence of volatilization (closed flasks), the decrease in concentration in both the phases was lower. The presence of sediment therefore,... 

Figure 1. Effect of adjuvants on the degradation of fenitrothion and aminocarb (17).

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