Invisible Toxins: New Research Exposes Ganga’s Chemical Crisis

Patna: A new study has revealed the presence of emerging organic contaminants (EOCs) in the River Ganga and its key tributaries, highlighting pollution trends from Varanasi to Begusarai. Co-authored by Dr. Ashok Ghosh, Professor and Head of Research at Mahavir Cancer Institute and Research Center, Patna, the study was published in Science Direct, an extensive database of peer-reviewed scientific literature maintained by Elsevier.

The research, conducted along a 500 km stretch of the Ganga in the middle Gangetic Basin, detected 51 EOCs in surface water samples. These include pharmaceuticals, agrochemicals, industrial chemicals, and lifestyle products, with the highest concentrations found in artificial sweetener sucralose, which serves as a wastewater tracer. The study noted a significant downstream reduction in contamination between Varanasi and Begusarai, likely due to dilution from three major tributaries: the Ghaghara, Sone, and Gandak rivers.

The findings raise concerns about the persistence of certain pollutants, particularly antibiotics like sulfamethoxazole, which exceeded predicted no-effect concentrations (PNEC) in five samples. The study also highlighted the presence of pesticides such as atrazine and imidacloprid, as well as industrial chemicals like perfluorooctane sulfonate (PFOS), known for their potential health risks.

Patna, as Bihar’s largest urban centre, was identified as a key location in the study, with researchers drawing comparisons between surface water and groundwater EOC levels in the city. The study found that concentrations of contaminants in groundwater were generally lower than in surface water, suggesting that the Ganga acts as a sink rather than a source for groundwater pollution in the region.

Dr. Ghosh emphasized the need for enhanced monitoring and regulatory action to curb pollution in the Ganga, especially in the wake of the Namami Gange initiative. “While the government has taken steps to clean the river, our findings underscore the need for a more comprehensive approach that includes systematic tracking of these contaminants,” he said.

The study also explored the potential of fluorescence-based monitoring techniques as a cost-effective method to identify pollution hotspots. This could prove crucial for regions like Bihar, where large-scale water contamination has public health implications.

The research, published in Environmental Pollution, contributes to a growing body of evidence on the impact of industrial and agricultural activities on India’s most sacred river. As Bihar continues its efforts towards sustainable water management, experts believe such studies will be vital in shaping future policies to protect the Ganga and its tributaries.