Đang chuẩn bị nút TẢI XUỐNG, xin hãy chờ
Tải xuống
Introduction: Pyrethroids are the general term for insecticide pyrethrins and their analogs (cinerins and jasmolins) being included in the flowers of pyrethrum or chrysanthemum. Trace concentrations of pyrethroids exert rapid toxic effects on insects, but are rapidly metabolized for detoxification in warm-blooded animals; they are insecticides with very high safety for humans. On the basis of clarification of chemical structures of the effective components of the pyrethrum, many of new synthetic pyrethroids were developed. Nowadays, the natural pyrethroids are almost replaced by the synthetic ones. They are not only being used for household insecticides, but also being used in agriculture. | 5. II.5.4 Permethrin by Naoto Matsumoto Introduction Pyrethroids are the general term for insecticide pyrethrins and their analogs cinerins and jasmolins being included in the flowers of pyrethrum or chrysanthemum. Trace concentrations of pyrethroids exert rapid toxic effects on insects but are rapidly metabolized for detoxification in warm-blooded animals they are insecticides with very high safety for humans. On the basis of clarification of chemical structures of the effective components of the pyrethrum many of new synthetic pyrethroids were developed. Nowadays the natural pyrethroids are almost replaced by the synthetic ones. They are not only being used for household insecticides but also being used in agriculture worldwide. They count about 1 3 of the total insecticides and are even increasing at the present time. Products containing pyrethroid insecticides are numerous their toxicities for humans are generally low. However since phenotrin permethrin and empenthrin are ubiquitous as powders emulsions and moth repellants for clothes there are possibilities of their accidental and suicidal ingestion. Permethrin Figure 4.1 3-phenoxybenzyl 1RS -cis trans-3- 2 2-dichlorovinyl -2 2-dimethylcyclopropane-1-carboxylate is one of the pyrethroids with the lowest toxicities and being used very widely the author et al. 1 experienced an actual case of ingestion of a large amount of permethrin-containing emulsion Adio Agros Tokyo Japan and measured the concentrations of its cis and trans isomers in blood and gastric juice. In this chapter a method of HPLC analysis for permethrin in serum is presented. O Figure 4.1 Cl Structure of permethrin. Reagents and their preparation Pure cis- and ira s-permethrin isomers can be obtained from Wako Pure Chemical Industries Ltd. Osaka Japan the mixture of the isomers from ICN Costa Mesa CA USA . In the case of the mixture the confirmation of the composition ratio is essential. The standard permethrin methanolic solution is prepared at .
