[Level of organochlorine pesticides in serum of Beijing residents in 2017].

Objective: To preliminarily investigate the exposure levels and distribution characteristics of organochlorine pesticides(OCPs) in serum of Beijing residents.

Methods: A total of 197 serum samples were randomly selected from the baseline samples of the Beijing Population Health Cohort study collected in 2017. The concentrations of 11 OCPs, including α-hexachlorocyclohexane(α-HCH), β-hexachlorocyclohexane(β-HCH), γ-hexachlorocyclohexane(γ-HCH), p, p'-dichlorodiphenyldichloroethylene(p, p'-DDE), p, p'-dichlorodiphenyldichloroethane(p, p'-DDD), p, p'-dichlorodiphenyltrichloroethane(P, P'-DDT), pentachlorobenzene(PCB), hexachlorobenzene(HCB), pentachlorophenol(PCP), pentachloronitrobenzene(PCNB), and dieldrin, were determined by solid-phase extraction coupled with gas chromatography-tandem mass spectrometry. The relationships among OCPs concentrations and gender, residence, age and body mass index(BMI) were assessed.

Results: At least three OCPs were detected in each sample, with concentrations ranging from 0.003 to 50.700 μg/L. Ten out of the eleven OCPs were detected, excluding PCNB. The detection rates of five OCPs exceeded 50%, namely p, p'-DDE, β-HCH, HCB, PCP and PCB, with median concentrations of 3.768, 0.966, 0.762, 0.414 and 0.050 μg/L, respectively. The serum concentrations of β-HCH(Z=-4.32, P<0.01) and HCB(Z=-2.01, P=0.04) were significantly lower in males than in females, and urban residents showed significantly elevated serum levels of p, p'-DDE(Z=-3.38, P<0.01), β-HCH(Z=-3.04, P<0.01), PCP(Z=-2.04, P=0.04) and PCB(Z=-2.16, P=0.03) relative to suburban residents. BMI was positively correlated with serum β-HCH concentrations(r=0.21, P<0.01).

Conclusion: Widespread exposure of OCPs was observed in the serum of Beijing general residents in 2017. Gender, residence and BMI may serve as significant factors influencing serum OCP levels.