Method For Determination Of Pyrethroid Pesticide Residues In Tobacco

Quantity of the pesticide residues in tobacco,directly affects the international market on the evaluation and purchase of tobacco trade,it is an important manifestation of the quality of the goods.At present,people pay attention to pesticide residue more and more,it will affect people’s health and the environment.The pyrethroid insecticide with high efficiency insecticidal effect,is the present domestic tobacco planting areas of extensive use of organic pesticide.This paper mainly studies determination method of the tobacco of pyrethroids pesticide residue,in order to expand China’s tobacco pyrethroid insecticide determination system.This paper introduces the determination of pesticide residues analysis methods,and doing experiments to establish two determination of pyrethroid pesticides in tobacco pesticide residue method, and this paper explores the tobacco sample cooling treatment on the chromatogram peak shape,the main content is divided into the following sections:(1) Utilization of acetonitrile-toluene solution treating tobacco samples,confirmed by experiments such as cypermethrin5kinds of pyrethroid pesticide,we can make elution time,the time is17.5-32.0min, and we make establishment of a chromatography apparatus operating condition,the method through the experiment results shows that:the average recovery of the method for97.40%-103.87%,the relative standard deviation is2.71%-7.83%,the experimental method is accurate and reliable.(2) By Petroleum ether extraction method to extract pesticide residue, through experimental contrast,the pesticide trace analysis effect is better; changing the pretreatment of solid-phase extraction in toluene/isooctane volume ratio selection optimization conditions,proved through the experiments:toluene/isooctane volume ratio of1.5:1as the method of optimal conditions.The average recovery of this method was93.21%-103.75%,the relative standard deviation is3.28%-6.20%,,the experimental method is accurate and reliable.(3) In order to make the more perfect method,the author further discusses the tobacco sample cooling treatment,by gas chromatography profile,found in tobacco sample cooling treatment on the chromatogram has a certain influence of peak shape,especially the existence of isomers tof pyrethroid material,We dissolve that after cooling for15-20minutes, isomers can be well separated from the peak shape and peak shape,is very clear.