Heavy metal contamination on surface water from pharmaceutical effluents in industrial zones: pollution levels and health risk assessment

Abstract

Industrial effluents from pharmaceutical facilities are introducing toxic metals into rivers and lakes, creating persistent pollution that bioaccumulates in aquatic life and threatens human health. Employing ICP‑MS, ten heavy metals were quantified in river water collected adjacent to pharmaceutical manufacturing areas, enabling precise detection of trace-level contaminants. Contamination severity was evaluated using multiple indices: Nemerow Pollution Index, Heavy Metal Evaluation Index, and Heavy Metal Pollution Index, etc. Analysis showed that lead (Pb), iron (Fe), and mercury (Hg) often exceeded WHO permissible limits, with the Up-stream (Turag River) showing higher levels of contamination than the Down-stream (Shitalakshya River). HPI and HEI values indicated severe pollution, while NPI and Cd also reflected serious water quality deterioration. The evaluation revealed notable health hazards, with both non‑cancer and cancer- associated risks markedly higher for children compared to adults. This integrative approach, combining advanced ICP‑MS analysis with multimetric pollution indices and health risk evaluation, highlights an urgent call for more rigorous effluent regulation, continuous water quality surveillance, and mitigation strategies to preserve ecological integrity and public well‑being.