Comprehensive risk assessment on groundwater heavy metal contamination in quality-induced water scarcity regions:case of Jiaxing City
Jiaxing,a city known for its quality-induced water scarcity,was chosen as the research area.Water samples were collected from 29 groundwater points to detect the concentrations of Fe,Mn,Cu,As,Pb,Hg,Cd,Cr,and pH.The Nemerow index and potential ecological risk index methods were employed to evaluate the degree of heavy metal pollution.Spatial distribution characteristics and sources of heavy metals were analyzed using geostatistical analysis and mathematical statistics.A risk assess-ment model was used to quantify the health risks to residents caused by this pollution.The results showed that the average concen-trations of Fe,Mn,As,and Pb in the groundwater of the study area exceeded the limit of the Class Ⅲ standard,with exceeding rates of Fe(86.2％)>Mn(75.9％)>As(62.1％)>Pb(20.7％).The other four elements did not exceed the Class Ⅲ stand-ard.The sources or migration and transformation pathways of Fe,Mn,and Cd were similar,and groundwater with high As content was weakly alkaline.The research area's comprehensive potential ecological risk index was 69.27,with an ecological hazard level ranging from mild to moderate.Furthermore,the total groundwater health risk in 93.1％of the study area was higher than the maximum acceptable value for adults,with the highest risk found in the southern area of Haining City and Haiyan County.These findings provide valuable data support and a theoretical basis for groundwater exploitation and utilization,and heavy metal pollu-tion control and risk management in quality-induced water scarcity regions.
groundwaterheavy metal pollutionNemerow index methodecological risk quantificationhealth risk evalua-tionJiaxing Cityquality-induced water scarcity regions
国家科技期刊平台
NSTL
万方数据
