POLLUTION STATUS AND HEALTH RISK ASSESSMENT OF A SPECIFIC ORGANOPHOSPHATE PESTICIDE-CONTAMINATED SITE

Organophosphate pesticide pollution is a severe global environmental issue, posing significant threats to human health. This study focuses on an organophosphate pesticide production site in North China. Controlled soil and groundwater were sampled using grid sampling and direct-push technology. Analytical methods such as headspace gas chromatography-mass spectrometry (GC-MS), gas chromatography (GC), and purge and trap GC-MS were employed to detect contaminants, including volatile organic compounds (VOCs), semi-volatile organic compounds (SVOCs), pesticides, and heavy metals. The results indicate that the maximum exceedances in the contaminated soil for benzene, xylene, trichloromethane, Parathion, phosphorodithioic acid, Phorate, and Terbufos were 490.63, 411.22, 3459.09, 507.89, 277.29, 1946.15, and 281.5 times the standard limits, respectively. In groundwater, benzene, dichloromethane, trichloromethane, and Phorate exceeded the standard limits by 220.83, 1374, 1853.33, and 806.67 times, respectively, severely contaminating the local soil and groundwater and damaging the ecosystem. Additionally, the carcinogenic risk values in the contaminated soil for benzene, toluene, phechloromethane, naphthalene, and aniline were 2.75E-3, 1.36E-2, 1.034E-2, 9.72E-1, 1.5E-3, 8.9E-3, 1.85E-3, 4E-3, 3.48E-2, 2.7E-2, 1.03E-3, respectively. In groundwater, toluene, xylene, dichloromethane, and trichloromethane showed carcinogenic risk values of 8E-3, 1.86E-2, 1.23E-2, 3.07E-2, respectively, significantly exceeding the acceptable limits and posing severe threats to the health of nearby residents. Furthermore, the hazard quotient for non-carcinogenic effects of Cypermethrin in soil was 1.15, and 2,6-dichlorophenol in groundwater was 1.22, both slightly above the standard, indicating a mild impact on the health of nearby residents. Overall, this study provides a theoretical basis for subsequent remediation work at the contaminated site through pollutant analysis.