title: Arsenic and heavy metals contamination, risk assessment and their source in drinking water of the Mardan District, Khyber Pakhtunkhwa, Pakistan.
abstract: The present study was conducted to investigate the physico-chemical characteristics in drinking water of Mardan District, Pakistan. Furthermore, water quality was evaluated for the risk assessment of arsenic and heavy metals (HMs) and their contamination sources. Representative groundwater samples of shallow and deep sources were collected in the study area. These samples were analyzed for physical parameters, anions, light metals (LMs) and HMs. Results were compared with the drinking water guideline values set by the World Health Organization and the US Environmental Protection Agency. Average concentrations of anions, LMs and HMs were found within the maximum allowable contaminant levels except for bicarbonates, Fe, Cu, and Pb. Results revealed that hazard quotients >1 were observed for shallow groundwater for 10% samples only, suggesting potential health risk from water consumption. Correlation analysis and principal component analysis showed a relationship among various physico-chemical parameters in both shallow and deep groundwater. Statistical analyses suggested the geogenic and anthropogenic sources for possible enhancement of various physico-chemical parameters in the aquifer system of the study area.
authors.affiliation: National Centre of Excellence in Geology, University of Peshawar, Peshawar 25120, Pakistan.
authors.forename: Nida
authors.initials: N
authors.lastname: Gul
authors.affiliation: National Centre of Excellence in Geology, University of Peshawar, Peshawar 25120, Pakistan.
authors.forename: Mohammad Tahir
authors.initials: MT
authors.lastname: Shah
authors.affiliation: Department of Environmental Science, University of Peshawar, Peshawar 25120, Pakistan.
authors.forename: Sardar
authors.initials: S
authors.lastname: Khan
authors.affiliation: National Centre of Excellence in Geology, University of Peshawar, Peshawar 25120, Pakistan.
authors.forename: Nimat Ullah
authors.initials: NU
authors.lastname: Khattak
authors.affiliation: Department of Earth Sciences, COMSATS Institute of Information Technology, Abbottabad 22060, Pakistan E-mail: saidmuhammad1@gmail.com.
authors.forename: Said
authors.initials: S
authors.lastname: Muhammad
mesh_terms: D001151:Arsenic / Q000032:analysis*; D060766:Drinking Water / Q000032:analysis*; D004784:Environmental Monitoring; D060587:Groundwater / Q000032:analysis; D019216:Metals, Heavy / Q000032:analysis*; D010154:Pakistan; D018570:Risk Assessment; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D060766:Drinking Water; D019216:Metals, Heavy; D014874:Water Pollutants, Chemical; D001151:Arsenic