Children more vulnerable to toxic metals in river: new study

A new study has found that children are at significantly higher risk than adults from exposure to trace metal contamination in river systems, raising concerns over water safety in parts of northern India.

The research, conducted by scientists from the Birbal Sahni Institute of Palaeosciences under the Department of Science and Technology, analysed water samples from the Betwa–Yamuna confluence in Uttar Pradesh’s Bundelkhand region.

Published in Nature Scientific Reports, the study shows that children face higher cumulative non-carcinogenic risks, with hazard levels exceeding safety thresholds in nearly 67 per cent of simulated scenarios. Arsenic exposure was also found to pose a considerable carcinogenic risk under real-world conditions.

Researchers moved beyond conventional methods of assessing average contamination levels and instead applied advanced risk modelling, including Monte Carlo simulations, to account for variations in human exposure. The analysis covered metals such as arsenic, lead and cadmium, factoring in variables like water intake, body weight and seasonal pollution changes.

The findings build on earlier research indicating that sediments in the Ganga Plain act as both storage and secondary sources of toxic metals, which can re-enter river water under changing environmental conditions.

The study points to multiple pollution sources, including agricultural runoff, untreated industrial discharge, thermal power activity and urban sewage. It also notes that contamination levels tend to rise at river confluences due to cumulative upstream inputs and mixing of water systems.

Highlighting the widespread use of river water for domestic and agricultural purposes, the researchers have called for targeted interventions to control heavy metal pollution and strengthen water quality monitoring.

The study proposes an integrated and uncertainty-based approach for river health assessment, which could help guide evidence-based policies and mitigation strategies, particularly in developing regions.