Evaluation of Human Health Risks Associated with Groundwater Contamination and Groundwater Pollution Prediction in a Landfill and Surrounding Area in Kaifeng City, China

Abstract

Landfill accumulation can cause its leachate to seep into groundwater, which can lower the quality of local groundwater. Exploring the risks of groundwater contamination to human health in the area around a landfill can offer a clear understanding of the current situation of regional groundwater and provide a theoretical basis for groundwater remediation and governance. By taking a landfill in Kaifeng City, China as the research object, this study explored the chemical types and sources of groundwater in the study area, used the entropy-weighted water quality index (EWQI) to evaluate the groundwater quality and assessed human health risks in the study area. The results show that the groundwater in the study area is neutral (7.14 ≤ pH ≤ 7.86), and the water chemical type is HCO3−—Ca·Na. The EWQI results indicated that the overall water quality in the study area ranges from 48.4 to 250.26, which is above the medium level, and that the local water quality is poor. The deterioration of groundwater quality in the study area is mainly influenced by NH4+-N, Mn, As, F- and Pb. According to the human health risk assessment model, the non-carcinogenic risk to humans through oral and dermal exposure can be assessed. In this paper, five ions, NH4+-N, Mn, As, F- and Pb in groundwater, were selected for the analysis of groundwater in the study area to assess non-carcinogenic risk to humans through oral administration. The results showed that the hazard quotient (HQ) values for NH4+-N, Mn, As, F− and Pb varied in the following ranges: 9.14 × 10−4—0.03; 0.07—0.22; 0.02–0.07; 0.16—0.23; and 0.01—0.13, respectively (all of these are less than 1, and so the potential risks to human health can be ignored). The characteristic pollutant Pb was selected as a predictor to study the influence on groundwater quality in eastern fish ponds and farmlands under continuous leakage. The leakage can be detected timeously to reduce the effects downstream by using enhanced monitoring measures.