The invention discloses a method for simultaneously analyzing polychlorinated biphenyls, polycyclic aromatic hydrocarbons and organochlorine pesticides in water, which comprises the following steps: simultaneously extracting polychlorinated biphenyls, polycyclic aromatic hydrocarbons and organochlorine pesticides in a
water sample by using a mixed
solvent of n-
hexane and
dichloromethane, merging while extracting, purifying, concentrating and fixing volume, and testing on a
machine in two groups, the
polychlorinated biphenyl and the
organochlorine pesticide are independently used as a group, the
polycyclic aromatic hydrocarbon is used as a group, when an extraction
solvent adopts a mixed
solvent of
dichloromethane and n-
hexane, the extraction efficiency is gradually increased along with the increase of the proportion of the n-
hexane, and when the volume ratio of the n-hexane to the
dichloromethane is 9: 1, the extraction
recovery rate can reach 78.9%-111%. When 1% of
polyethylene glycol 4000 is added in the mixed extraction process with the volume ratio of n-hexane to dichloromethane being 9: 1, the extraction efficiency is remarkably improved, the extraction efficiency
recovery rate reaches 84.6%-112%, and it is indicated that the addition of
polyethylene glycol 4000 has the remarkable improvement effect. Compared with the prior art, the extraction efficiency is remarkably improved, and the
accuracy and precision of the method completely meet the determination and analysis requirements for measuring complex water samples.