Composition and potential risks of agricultural chemical pesticides presented in the potential drinking water sources of groundwater from rural area, eastern ChinaAuthor(s): Hongjun Lei, Hongwei Pan, Beidou Xi, Ting Xu
Groundwater is an important water resource in the lower Yellow River rural area. In recent years, with the arid events occurred more and more frequent, the drinking water problem in the rural areas has been deteriorating. For the releasing the pressure of drinking water scarce, more and more groundwater has been explored and used as drinking water. However, the information on the studies of groundwater quality and human health risks brought by drinking polluted groundwater greatly lacks. In this study, the rural area locates in the Shandong Province of lower Yellow River with heavy agricultural chemical pesticides application amount was chosen to study the composition, levels and potential human health risks of pesticides residue in the groundwater. Results showed that forty-two types of pesticides were analyzed, among which seven types of pesticides were detected in the groundwater samples. Among the detected pesticides, imidacloprid had the highest level with a concentration of 58.915±16.114 μg/L, and p,p'-DDD, phenthoate, diazinon, chlorpyrifos, endosulfan and o,p'-DDT had a concentration of 2.596, 2.170, 1.198, 0.946, 0.665 and 0.280 μg/L, respectively. This indicated that imidacloprid was easier to transport into the groundwater than other pesticides in the study area. However, the human health risk evaluation results showed that low level of diazinon exhibited a high human health risk with the HI value of higher than 0.1, while the highest level compound of imidacloprid showed a low human health risk with the HI value of 0.01~0.1. This revealed that low level of pesticides in the groundwater would also pose high human health risk. Therefore, the evaluation of pesticides pollution in the groundwater should not only judged by the investigation of the residue level but also should be evaluated its human health risk. Because diazinon in the groundwater of the study area exhibited high human health risk, therefore this type of pesticides should be paid more attention to be observed and managed in order to insure safety water drinking.