Microplastics may pose environmental risk to Indo-Gangetic plain, says study

Panaji: According to a study by CSIR-National Institute of Oceanography (NOI), microplastics, particularly high-hazard polymers, pose a threat to the Indo-Gangetic plain. The research suggests that municipal corporations should devise action plans to address plastic pollution, targeting specific sources in each area. Microplastics are tiny plastic debris in the environment, formed from discarded consumer goods and industrial waste breakdown.

Titled ‘A comprehensive assessment of macro and microplastics from Rivers Ganga and Yamuna: Unveiling the seasonal, spatial and risk factors,’ the findings were published in the ‘Journal of Hazardous Materials’ on Saturday.

As per the study, conducted by a team led by CSIR-NIO principal scientist Dr Mahua Saha, microplastics were detected in the Ganga from Haridwar to Patna, with the pollutant concentration being higher during “wet (rainy) season than the dry season”.

During the wet season, Haridwar had the highest microplastic abundance in surface water, contrasting with Patna, which had the lowest. Conversely, in the dry season, Agra exhibited the highest concentration, while Patna and Haridwar had the lowest.

Researchers also utilized GIS and field surveys to pinpoint plastic leakage-prone areas. They noted distinct variations in microplastic levels across surface water, water columns, and sediments during wet and dry seasons along the Ganga and Yamuna rivers.

Moreover, the study revealed substantial waste transportation from upstream cities during the dry season, accumulating in the floodplain region.

These wastes get washed off during the wet season. “As a result, it is conceivable that over time, these macroplastics might have degraded into smaller pieces and subsequently transported into the adjacent river systems by urban run-off during the wet season,” said the study.

The dispersion of microplastics is not limited to localised areas in the Ganga and Yamuna rivers, it said.

“However, it is challenging to distinguish the exact incorporation of microplastics between locally generated plastics and those carried from upstream sources since many rivers pass through the residential areas and due to the lack of awareness, sometimes local deposition of plastics into the river is much higher,” the researchers said.