Study detects microplastics in HP’s glacier-fed Uhl River

According to researchers, the study provided baseline evidence of microplastic pollution in the Himalayan river, highlighting the spread of plastic contamination even in relatively undisturbed mountain environments

A new study has detected microplastics (MPs) in both water and sediment samples collected from the glacier-fed Uhl River in Himachal Pradesh, highlighting their widespread spread and ability to travel across the environment even in areas with little human activity.

Researchers found that fragments were the most common form of microplastics, followed by fibres and films. (HT Photo for representation)

The study investigated the occurrence, abundance, and characteristics of MPs in water and sediment samples collected from the River Uhl, originating from the Thamsar Glacier in the Dhauladhar range.

According to researchers, the study provided baseline evidence of microplastic pollution in the Himalayan river, highlighting the spread of plastic contamination even in relatively undisturbed mountain environments.

The study, published in Discover Environment journal, has been conducted by a team of researchers from Central University of Himachal Pradesh (CUHP), Lovely Professional University (LPU) and Amity University Haryana.

The researchers collected water and sediment samples from three sites (Kukkar Gundha, Zero Point and Barot) along the Uhl River, representing different levels of human influence. Collected samples were analysed using microscopy and fourier-transform infrared (FTIR) spectroscopy.

The study found lower microplastic concentrations at the relatively undisturbed site, ranging from 50 to 100 particles per litre of water or per kilogram of dry sediment. Downstream sites recorded higher concentrations, ranging from 100 to 500 particles per litre of water or per kilogram of dry sediment.

Researchers found that fragments were the most common form of microplastics, followed by fibres and films. Colourless particles were predominant, followed by blue, purple and yellow particles, indicating a possible link with commonly used consumer plastics.

Reshma Sinha, assistant professor at CUHP’s department of animal sciences, who is one of the authors of the study, said, “MPs pollution in freshwater ecosystems is a growing environmental concern, particularly in the fragile Himalayan river systems. MPs concentrations varied significantly across the sampling sites. The findings suggest that human activities may influence the distribution of microplastics.”

“The detection of MPs at Kukkar Gundha indicates that these pollutants have reached and persist in less-disturbed Himalayan environments. Further analysis using FTIR confirmed polystyrene, polyethylene and polypropylene among the polymers present in the samples. Variations in the results across sites and between water and sediment samples suggested differences in plastic sources and levels of degradation,” she added.

However, the researchers said further research and long-term monitoring would be needed to understand the extent and seasonal variations of microplastic pollution in Himalayan rivers.

The study has called for measures to reduce plastic pollution, including promoting sustainable consumption, developing environmentally friendly alternatives to conventional plastics, improving waste disposal methods, waste-water management and strengthening long-term monitoring.

“These findings underscore the need for continuous monitoring and targeted management strategies to mitigate MPs pollution and protect freshwater ecosystems in the Himalayan region,” the researchers said.

Microplastics can disrupt feeding, reproduction and organ functions in fish and other aquatic animals. In humans, exposure through contaminated food, water and air may cause inflammation, cell damage, immune reactions and reproductive problems. Studies have also suggested possible links between microplastic exposure and chronic diseases.

After its origin at Thamsar Glacier, the Uhl River travels downstream and cuts through the Chota Bhangal region of Kangra before crossing the border into Mandi district near Barot. The findings of the study have raised concerns over the impact of increasing tourism, plastic consumption and improper waste disposal on fragile mountain ecosystems. Areas like Chota Bhanghal along with the adjoining Barot valley, have witnessed a rise in tourist arrivals over the past decade.