Source apportionment and health risk assessment of arsenic contamination in groundwater in Xinxiang city based on the PCA-PMF model and WQI method

Seasonal variability in groundwater quality and its implications for human health risk in Guwahati City, Assam, India

Groundwater quality assessment is essential for ensuring safe drinking water, given that groundwater serves as a primary water source. The quality of groundwater is deteriorating due to population growth and urbanization. This study evaluates groundwater quality in Guwahati City, Assam, India, by analyzing basic hydrochemical parameters and trace element concentrations. The findings indicate that fluoride (F-) originates mainly from geogenic processes. Elevated arsenic (As) concentrations in one well are likely linked to local anthropogenic sources, while widespread manganese (Mn) and lead (Pb) contamination across the city may result from industrial wastewater and landfill leachate. The dominant hydrochemical facies was Ca-Mg-HCO3 during the dry, pre-monsoon, and monsoon seasons, shifting to Na-K-HCO3 in the post-monsoon season, potentially influenced by ion-exchange processes. Cluster analysis identified poor water quality in the northeastern part of the city, and principal component analysis demonstrated that both geological and anthropogenic factors affect water quality. Human health risk assessment further revealed that children are more susceptible to non-carcinogenic health risks, whereas adults are more vulnerable to carcinogenic health risks. These findings highlight the need for targeted groundwater monitoring and pollution control to protect public health, particularly among vulnerable populations.

Geostatistical and PMF-based source apportionment of heavy metal contamination in the groundwater of Faisalabad, Pakistan: water quality and health risk assessment

Groundwater Quality Assessment, Trace Element Pollution, and Health Risk Assessment of Hand-Dug Wells within Ladoke Akintola University of Technology Campus and Environs, Ogbomoso, Southwestern Nigeria

Groundwater is the primary source of potable water within Ladoke Akintola University of Technology (LAUTECH). Natural geochemical processes and increasing anthropogenic activities may compromise its quality and pose potential health risks. This study evaluated the physicochemical characteristics, trace-element concentrations, groundwater pollution status, and associated health risks of groundwater from thirty-nine (39) hand-dug wells. Sixteen (16) wells were selected for detailed pollution-index and health-risk assessments based on their spatial distribution and contamination characteristics. Physicochemical parameters and trace-element concentrations were determined using standard analytical procedures. Groundwater pollution was evaluated using the Heavy Metal Pollution Index (HPI), Heavy Metal Evaluation Index (HEI), and Contamination Index (Cd). Health risks were assessed using United States Environmental Protection Agency (USEPA, 2011) models based on the Hazard Quotient (HQ), Hazard Index (HI), and Cancer Risk (CR). The groundwater was moderately acidic to neutral (pH 4.92–6.94), and most physicochemical parameters complied with the World Health Organization (WHO, 2022) and Nigerian Standard for Drinking Water Quality issued by the Standards Organisation of Nigeria (SON, 2015) guideline values. Elevated concentrations of cadmium (Cd), lead (Pb), and nickel (Ni) were detected in representative wells, resulting in varying degrees of groundwater contamination. The HI ranged from 0.216 to 0.639 for adults and from 0.504 to 1.491 for children. All adult HI values were below the acceptable threshold, whereas selected wells recorded values greater than one for children, indicating potential non-carcinogenic health risks. Total Cancer Risk (TCR) values ranged from 1.23 × 10⁻³ to 3.72 × 10⁻³ for adults and from 2.87 × 10⁻³ to 8.68 × 10⁻³ for children, exceeding the USEPA acceptable cancer-risk range (10⁻⁶–10⁻⁴) in all assessed wells. Cadmium and nickel were the principal contributors to carcinogenic risk. The results emphasise the need for continuous groundwater-quality monitoring, effective waste management, source protection, and appropriate groundwater treatment to safeguard public health.

Groundwater Contamination and Probabilistic Health Risk Assessment of Heavy Metals in Coal Mining Areas of Punjab, Pakistan

Source Apportionment and Health Risks of Toxic Metals in Groundwater from a Dual-Aquifer Coal Mine System

Heavy metal contamination in mining-affected groundwater may pose potential risks to drinking water safety and human health. In this study, 25 groundwater samples, including 18 from Aquifer IV of the Cenozoic unconsolidated porous aquifer system and 7 from the Taiyuan Formation limestone karst aquifer, were collected from the Zhuxianzhuang Coal Mine, Huaibei Coalfield, China. The Heavy Metal Pollution Index (HPI), Metal Index (MI), Positive Matrix Factorization (PMF), and oral-ingestion health risk model were applied to assess metal contamination, source contributions, and human health risks. HPI values ranged from 8.0 to 37.5, with a mean of 21.5, indicating a low overall pollution level. In contrast, MI values suggested cumulative metal contamination, with higher mean values in Taiyuan Formation limestone karst groundwater (5.60) than in Aquifer IV groundwater (2.38). PMF identified two major factors, interpreted as a natural water–rock interaction source and a combined anthropogenic and mining-related source. Health risks were consistently higher in Taiyuan Formation limestone karst groundwater. Non-carcinogenic risks were higher for children and mainly controlled by As, whereas carcinogenic risks were higher for adults and mainly associated with Cr. These findings highlight the need for aquifer-specific monitoring and source control to reduce toxic metal exposure in coal mining areas.

Source apportionment of heavy metals via PMF-space auto-correlation and source-oriented human health risk assessment: identification of priority control factors