摘要
The degradation and fate of pesticide N' (2,4 dimethylphenyl) N methylformamidine hydrochloride in simulated aquatic ecosystem were investigated. The results showed that the pesticide was not stable in simulated aquatic ecosystem with pH value of 7.4—8.9 and water temperature of 18.0—26.5℃. In the first 9 days, 95% of DMAH was disappeared, whereas the concentration of its degradation product 2,4 dimethylformanilide increased with time and was of a maximum value at about 9 days and then decreased. The concentration of 2, 4 dimethylaniline, which is another degradation product of DMAH, nearly did not change in the early of experiment. However, it decreased rapidly after 9 days. The experiment lasted 51 days. At the end of experiment, there were no N' 2, 4 dimethylphenyl) N methylformamidine, 2, 4 dimethylformanilide and 2, 4 dimethylaniline detected in water, but they were all detected in the sediment and water grass, and the total amount of them covered 2%—3% of application amount of DMAH. It indicated that water grass and sediment could absorb and concentrate these compounds.
The degradation and fate of pesticide N' (2,4 dimethylphenyl) N methylformamidine hydrochloride in simulated aquatic ecosystem were investigated. The results showed that the pesticide was not stable in simulated aquatic ecosystem with pH value of 7.4—8.9 and water temperature of 18.0—26.5℃. In the first 9 days, 95% of DMAH was disappeared, whereas the concentration of its degradation product 2,4 dimethylformanilide increased with time and was of a maximum value at about 9 days and then decreased. The concentration of 2, 4 dimethylaniline, which is another degradation product of DMAH, nearly did not change in the early of experiment. However, it decreased rapidly after 9 days. The experiment lasted 51 days. At the end of experiment, there were no N' 2, 4 dimethylphenyl) N methylformamidine, 2, 4 dimethylformanilide and 2, 4 dimethylaniline detected in water, but they were all detected in the sediment and water grass, and the total amount of them covered 2%—3% of application amount of DMAH. It indicated that water grass and sediment could absorb and concentrate these compounds.
