Integrative model-based assessment of heavy metal contamination and source apportionment in groundwater of West Bengal, India

Abstract This research explores the levels of heavy metal (HM) contamination in the groundwater, along with their probable origin and distribution patterns across different sites of West Bengal, India. The HM concentrations are generally higher in site 2 compared to site 1, with As showing the highest levels at site 2, averaging 34.31 ± 9.07 μg · L −1 . The spatial distribution analysis revealed that HM pollution is more concentrated in the northern and western regions, highlighting these regions as the primary contamination zones across the study sites. The positive matrix factorization (PMF) analysis indicated that natural processes (31.08%) and traffic emissions (30.85%) are likely the key contributors to HM contamination in the groundwater. Additionally, the self-organizing map (SOM) analysis effectively identified the distribution pattern of HMs. Hence, this study offers insights into model-based analytical approaches that can support policymakers and environmental scientists in effectively monitoring and controlling HM contamination in groundwater on a global scale.