Health risk assessment of pesticide residues in urban wastewater in four cities of North China

Wastewater samples were collected from wastewater treatment plants in Beijing, Taiyuan, Hohhot and Shijiazhuang, and the concentrations of 21pesticides were analyzed. The total and average mass of pesticide residues in wastewater were calculated. According to consumption of vegetable and fruit and related processing factors, the pesticide residues on vegetables and fruits were estimated, and corresponding health risk was further evaluated. The residue level per thousand inhabitants was highest in Shijiazhuang (454.89mg/thousand inhabitants/d), and Hohhot had the lowest level (63.70mg/thousand inhabitants/d). Among the tested pesticides, the concentration of carbendazim was relatively high, 224.22~1328.07ng/L, and the residue level per thousand was 49.98 ~ 424.98mg/thousand inhabitants/d. Carbendazim accounted for the highest proportion of pesticide residues in the four cities, 51.35% (Beijing) ~ 93.43% (Shijiazhuang). Other pesticides with high proportion include imidacloprid and chlorantraniliprole, which showed a similar usage behavior of pesticide in vegetables and fruits in the region. The pesticide residues in vegetables and fruits are calculated based on the tested values in wastewater. The residue of carbendazim in vegetables and fruits in Shijiazhuang was 5.04mg/kg. By comparing the estimated potential daily intake with the daily allowable intake, the long-term health risk of these pesticide residues was relatively low. © 2022 Chinese Society for Environmental Sciences. All rights reserved.