Human health risk under the condition of farmland soil heavy metals pollution in a gold mining area

Human health effects of heavy metal pollution have constituted a major environmental problem at present. Mining activities lead to different degrees of accumulation or excess of heavy metals in soil, groundwater and crops in a gold mining area. The dietary structural parameters were obtained through sample collection and population exposure questionnaire. Based on the average content of heavy metals in the sample and using human health risk assessment model recommended by USEPA, the authors calculated adult health risk probability derived from oral ingestion (soil, groundwater, wheat, corn, vegetables), skin contact (soil, groundwater) and other exposure pathways. The results show that there are unacceptably high non-carcinogenic risks and cancer risks that threat human health because of the existence of heavy metals pollution in the study area. The severer the heavy metal pollution in soil, the higher the human health risks. There are some important factors that harm human health, such as chromium in groundwater, mercury in soil as well as vegetables and grains growing in polluted soil. Therefore, the following measures seem to be very important in protection of human health: to persuade local people not to drink groundwater with high chromium content and not to eat contaminated crops, to remedy polluted soil, and to adjust crop planting structure.