Health risks associated with heavy metals in the drinking water of Swat, northern Pakistan.
The concentrations of heavy metals such as Cd, Cr, Cu, Mn, Ni, Pb and Zn were investigated in drinking water sources (surface and groundwater) collected from Swat valley, Khyber Pakhtunkhwa, Pakistan. The potential health risks of heavy metals to the local population and their possible source apportionment were also studied. Heavy metal concentrations were analysed using atomic absorption spectrometer and compared with permissible limits set by Pakistan Environmental Protection Agency and World Health Organization. The concentrations of Cd, Cr, Ni and Pb were higher than their respective permissible limits, while Cu, Mn and Zn concentrations were observed within their respective limits. Health risk indicators such as chronic daily intake (CDI) and health risk index (HRI) were calculated for adults and children separately. CDIs and HRIs of heavy metals were found in the order of Cr > Mn > Ni > Zn > Cd > Cu > Pb and Cd > Ni > Mn > Cr > Cu > Pb > Zn, respectively. HRIs of selected heavy metals in the drinking water were less than 1, indicating no health risk to the local people. Multivariate and univariate statistical analyses showed that geologic and anthropogenic activities were the possible sources of water contamination with heavy metals in the study area.
State Key Laboratory of Urban and Regional Ecology, Research Centre for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. mr_khann84@yahoo.com
Yonglong
Y
Lu
Department of Environmental Sciences, University of Peshawar Peshawar 25120, Pakistan.
Hizbullah
H
Khan
Department of Environmental Sciences, University of Peshawar Peshawar 25120, Pakistan.
Shahida
S
Zakir
Nuclear Institute for Food and Agriculture, Tarnab, Peshawar, Pakistan.
Ihsanullah
Department of Environmental Sciences, University of Peshawar Peshawar 25120, Pakistan.
Sardar
S
Khan
Department of Environmental Sciences, University of Peshawar Peshawar 25120, Pakistan.
Akbar Ali
AA
Khan
State Key Laboratory of Urban and Regional Ecology, Research Centre for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
Luo
L
Wei
State Key Laboratory of Urban and Regional Ecology, Research Centre for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
Tieyu
T
Wang
D060766:Drinking Water / Q000737:chemistry*; D004784:Environmental Monitoring; D019216:Metals, Heavy / Q000737:chemistry*; D010154:Pakistan; D012307:Risk Factors; D014874:Water Pollutants, Chemical / Q000737:chemistry*
D060766:Drinking Water; D019216:Metals, Heavy; D014874:Water Pollutants, Chemical