Assessment of Heavy Metal Levels and Health Risks in Coal Mining Regions: A Geostatistical and Health Risk Assessment Approach

Coal mining is major source of heavy metal contamination in soil and water. Present research was conducted to evaluate the spatial distribution, metal levels, and associated human health hazards of different heavy metals. Samples were obtained from coal mining areas of Chakwal and Khushab districts, Punjab, Pakistan. Atomic absorption spectrophotometry (AAS) was used for analyzing samples. Results demonstrated that there were marked spatial and inter-district variations in concentration of metals including Cadmium (Cd), Lead (Pb), Zinc (Zn), Copper (Cu), Nickel (Ni), and Chromium (Cr). For health hazard evaluation estimated daily intake (EDI), hazard quotient (HQ), hazard index (HI), and lifetime cancer risk (LCR) were calculated for both elders and children. In both districts, ingestion emerged as the primary exposure pathway. In contrast to adults’ children were found to be more sensitive to these hazards due to their higher exposure relative to body weight. In Chakwal, elevated HI values were noticed for Cd in children (HI = 1.63), with Cr surpassing tolerable LCR range (LCR = 1.528E-04). Similarly, in Khushab, HI values for Cd outpaced the safety levels in both children and adults with statistically significant LCR values recorded for Cr and Cd in children. Soil samples were confirmed to be more hazardous compared to water. All HI and LCR values were within tolerable ranges in water samples. In conclusion, the findings emphasize the need for regular environmental monitoring and novel strategies to manage heavy metal accumulation in coal mining areas.