Cancer risk assessment and modeling of groundwater contamination near industrial estate, Lahore, Pakistan

Abstract

More than 60% of the population of Pakistan has no access to safe drinking water. Industrial zones near populated areas make conditions more severe due to continuous contamination. The aim of this study was to use statistical tools for correlation and source identification and health risk assessment of contamination due to Sundar Industrial Estate (SIE), Lahore, Pakistan. Drinking and wastewater samples were collected from SIE and analyzed for physical, chemical, microbial, and heavy metals analysis. Results showed that heavy metals and microbial contamination were beyond the National Drinking Water Quality Standards of Pakistan while high values of chemical oxygen demand (COD) and biochemical oxygen demand (BOD) wastewater were responsible for contamination of drinking water through seepage. There was a medium to strong correlation among parameters of all samples as indicated by Pearson correlation and analysis of variance. Principal component analysis and cluster analysis indicated sources of contamination, i.e., refuse leachate and untreated effluent discharges as main source of pollutants for drinking water. Health risk assessment showed a high intake of heavy metals through drinking water. Hazard quotient and hazard index indicated high probability of non-carcinogenic risk while cancer risk assessment suggested that out of every 100 of the population 93 people may suffer carcinogenic effects. HIGHLIGHTS Samples showed high bacterial and heavy metals contamination due to untreated effluent.; Statistical modeling showed strong correlation and seepage as the main source of pollution.; The hazard quotient and hazard index (for non-carcinogenic risk) values are >1.; Risk assessment showed 93 people out of 100 of population may suffer from cancer.;

Keywords

• correlation
• heavy metals
• risk assessment
• source
• statistical modeling