- 著者
- Toshiyuki Katagi Takuo Fujisawa
- 出版者
- Pesticide Science Society of Japan
- 雑誌
- Journal of Pesticide Science (ISSN:1348589X)
- 巻号頁・発行日
- pp.D21-028, (Released:2021-09-08)
- 参考文献数
- 160
- 被引用文献数
- 7
The median lethal dose of pesticide in acute oral toxicity, used as a conservative index in avian risk assessment, varies by the species with differences of less than one order of magnitude, depending on body size, feeding habit, and metabolic enzyme activity. The profiles of pesticide metabolism in birds with characteristic conjugations are basically common to those in mammals, but less information is available on their relevant enzymes. The higher toxicity of some pesticides in birds than in mammals is due to the lower activity of avian metabolic enzymes. The bioaccumulation in birds is limited for very hydrophobic pesticides resistant to metabolic degradation. Several in silico approaches using the descriptors of a pesticide molecule have recently been employed to estimate the profiles of acute oral toxicity and bioaccumulation.
- 著者
- Masahiro Nishiyama Yusuke Suzuki Toshiyuki Katagi
- 出版者
- 日本農薬学会
- 雑誌
- Journal of Pesticide Science (ISSN:1348589X)
- 巻号頁・発行日
- vol.35, no.4, pp.447-455, 2010-11-25 (Released:2010-11-24)
- 参考文献数
- 20
- 被引用文献数
- 5 7
Metofluthrin [I, 2,3,5,6-tetrafluoro-4-(methoxymethyl)benzyl (EZ)-(1R,3R)-2,2-dimethyl-3-(prop-1-enyl)cyclopropanecarboxylate] was resistant to hydrolysis at pH 4 and 7 but moderately hydrolyzed with a half-life of 36.8 days at pH 9 and 25°C to form the corresponding acid and alcohol via ester cleavage. The activation energy was estimated to be 105 kJ mol−1 based on the hydrolysis rates at 25–50oC. By continuous exposure to light at >290 nm from a Xenon arc lamp at hydrolytically stable pH 4 and 25°C, I was rapidly photodegraded with half-lives of 1.1–3.4 days, mainly via ester cleavage and successive oxidation followed by mineralization to carbon dioxide. Spectroscopic analyses together with co-chromatography with authentic standards showed that the major degradates having an ester linkage were the aldehyde and carboxylic acid derivatives formed via oxidative cleavage of the prop-1-enyl group together with the diol formed possibly through an oxidative intermediate, such as an epoxide.