Risk assessment of toxic metals and groundwater quality assessment in an industrial hotspot of Bengaluru, India – case study

Abstract

The present study was conducted across 28 sampling locations in an industrial zone (Peenya) of Bengaluru city to characterize the various chemical parameters of groundwater. Groundwater chemistry was evaluated using Water Quality Index (WQI) and Piper plots. The WQI results showed that around 78% of sampling points were unfit for drinking water consumption. Results of Piper plots categorized groundwater samples principally into Ca·Mg-HCO3 type (39%) and mixed Ca·Mg − Cl · SO4 type (53.5%). The study used principal component analysis and hierarchical cluster analysis to evaluate possible sources of water pollution. The five major principal components were extracted, and it showed that the water quality in the study area was likely influenced by both natural geogenic and anthropogenic sources. Water was not typically used for drinking purposes, but was used for various industrial uses. Human health risk assessment showed that in most sampling locations (86%), values of the Hazard Index were greater than 1, which indicated that water was not suitable for drinking because of its potential to cause non-carcinogenic health effects in adults and children. Long-term monitoring of contamination in the study area revealed that the concentration of Cr(VI) still existed at concerning levels in groundwater. Thus, the current study aids in identifying risks associated with heavy metal contamination and serves as a foundation for developing a remediation plan to address environmental issues.