Fingerprinting of heavy metal and microbial contamination uncovers the unprecedented scale of water pollution and its implication on human health around transboundary Hudiara drain in South Asia

Abstract

Environment and health hazards posed by the contamination of existing underground water resources are amongst the leading anthropogenic challenges in South Asia. One such major environmental hazard is posed by the transnational wastewater drain – Hudiara, which is degrading the quality of underlying aquifers. Towards a spatiotemporal assessment of Hudiara’s wastewater quality and drinking water from its adjoining areas, a total of 56 wastewater and 42 drinking water samples were obtained over seven months. Analysis of spatiotemporal data revealed a complex interplay of geogenic and anthropogenic factors underlying the HM burden leading to a high contamination factor(CF) (>6 for Mercury in wastewater and >150 for Arsenic in drinking water) and heavy metal pollution index(HPI) (>100 for 9 heavy metals). Moreover, high health risk assessment(HRA) scores (>1 for Arsenic, Mercury, Chromium, Lead, Cadmium, and Copper) indicated the unprecedented scale of drinking water contamination. A concomitant public health survey conducted in the surrounding population reported a high prevalence of gastrointestinal diseases (40%), chronic obstructive pulmonary diseases (COPD) (38.7%), dermatitis (34%), bone deformities (31%), and hepatic disorders (12%). Lastly, 16S rRNA sequences of Hudiara were submitted to the Comprehensive Antibiotic Resistance Database (CARD) and point mutations in the sequences were potentially found to confer antimicrobial resistance (AMR) against three classes of drugs including aminoglycosides, peptides, and tetracyclines. Taken together, this pilot study attempts to uncover the unprecedented scale of water contamination along the transboundary Hudiara drain thus highlighting the critical need for international regulatory action towards ameliorating its catastrophic effects on the environment.