Method for detecting weeding ether pesticide residues in soil

Abstract

The invention discloses a method for detecting herbicidal ether pesticide residues in soil, which comprises the following steps of: pressurizing and extracting herbicidal ether in the soil on a pressure solvent extraction instrument by using a dichloromethane and acetone mixed solvent, concentrating, purifying and carrying out solvent conversion on extract liquor, separating by using a gas chromatograph, and detecting by using a mass spectrum detector. A matrix labeling experiment shows that when the content of the herbicidal ether in a soil matrix sample is 0.2 mg / kg-2. 0mg / kg, the relative standard deviation (n = 6) of a measurement result is 4.0%-5.3%; when the addition scalar amount of the herbicidal ether in the soil matrix sample is 2 [mu] g, 5 [mu] g and 10 [mu] g, the recovery rates of the six times of independent determination are 93.5%-106%, 94.2%-104% and 95.2%-106% respectively; when the soil sampling amount is 10 g and the constant volume of the extract is 1.0 mL, the method detection limit of the herbicidal ether in the soil is 0.04 mg / kg, and the determination lower limit is 0.16 mg / kg. The mass spectrometric detector is adopted for determining the nature, the resolution ratio is high, and the anti-interference capability is high; the pressure solvent extractor is used for extracting soil samples, operation is convenient, and the automation degree is high; soil pollution investigation, risk assessment and repair evaluation can be met.

Description

technical field [0001] The invention belongs to the technical field of environmental detection, and relates to a detection method for herbicide residues in soil. Background technique [0002] Herbicide, chemical name 2,4-dichlorophenyl-4-nitrophenyl ether, is a contact herbicide. In June 2002, the Ministry of Agriculture issued Announcement No. 199 that herbicide is a pesticide prohibited by the state. In October 2017, the International Agency for Research on Cancer of the World Health Organization announced the list of carcinogens, and herbicide was included in the list of Class 2B carcinogens. Herbicides were once one of the main varieties of herbicide pesticides, widely used in agriculture and forestry weeding. Because the molecular structure of pesticides is generally relatively stable and difficult to degrade naturally, they will not degrade and disappear in the natural environment soon after application, but accumulate in soil, groundwater, surface water and marine w...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a soil sample extraction operation convenient, strong qualitative anti-interference ability, high quantitative accuracy of the determination method of pesticide residues of bibenbicide in the soil, using pressure solvent extraction instrument to extract the bibenbow ether in the soil, the extract is concentrated, After purification and conversion of the solvent to n-hexane, it enters the gas chromatograph for separation and is detected by a mass spectrometer to solve the technical defects of existing detection methods in qualitative analysis, sample extraction, etc.

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