Microplastic contamination and environmental risks in the Beas River, western Himalayas

Ritindra N Bhaduri; Sougata Sinha; Angelina M Guererro; Sonja L Jackson; Elvin A Alemán; Subhankar Chatterjee

doi:10.1016/j.envpol.2024.125387

Microplastic contamination and environmental risks in the Beas River, western Himalayas

Environ Pollut. 2024 Nov 23:365:125387. doi: 10.1016/j.envpol.2024.125387. Online ahead of print.

Authors

Ritindra N Bhaduri¹, Sougata Sinha², Angelina M Guererro³, Sonja L Jackson³, Elvin A Alemán⁴, Subhankar Chatterjee⁵

Affiliations

¹ Department of Biological Sciences, California State University Stanislaus, One University Circle, Turlock, CA, 95382, USA. Electronic address: rbhaduri@csustan.edu.
² School of Chemical Sciences, Indian Institute of Technology Mandi, Kamand-175005, Himachal Pradesh, India.
³ Department of Biological Sciences, California State University Stanislaus, One University Circle, Turlock, CA, 95382, USA.
⁴ Department of Chemistry, California State University Stanislaus, One University Circle, Turlock, CA, 95382, USA.
⁵ Department of Ecology and Environmental Sciences, Pondicherry University, Puducherry, 605014, India. Electronic address: schatt.pondiuni@gmail.com.

PMID: 39586456
DOI: 10.1016/j.envpol.2024.125387

Abstract

The Western Himalayan mountains, with several riverine systems, are considered one of the most fragile environments in the world. Among them is Beas, a primary river that provides essential ecosystem benefits to thousands of indigenous people in North India. One of the major pollutants, microplastics (MPs), are ubiquitous contaminants, yet their occurrence in the Beas and ecological risk factors remain largely unexplored. Due to extensive tourism and urban-related burdens, the usage and release of enormous amounts of plastics and MPs into the Beas are apparent. Here, we investigated the extent of MPs pollution and subsequent environmental risks in water and sediments from Beas along a stretch of 300 km. Our results showed that MPs were abundant and widely distributed, with the abundance range (mean ± SE) being 46-222 (112.27 ± 12.43) items/L in water and 36-896 (319.47 ± 49.25) items/kg in sediment samples. We found significant differences in MPs' abundance in water but not sediments among the five sampling sites. There was a significant positive correlation between population size and the abundance of MPs, with the highest abundance in populated Kullu and the lowest loads at the remote Dhundi Glacier. Fibers and film were common morphotypes; most items measured <1 mm. Of the eleven polymers identified, the majority were polyethylene. The pollution load index ranged up to 4.99 (low-risk category); however, the polymer hazard index exceeded 1000 (highest-risk category), and the potential ecological risk index was 13,761 (extreme-risk category) at selected sites. This study fills a crucial knowledge gap and raises concerns about the possible impact on human health, as many riparian residents depend on Beas as their primary source of potable water. Our findings may assist governmental agencies in formulating comprehensive eco-friendly policies and advancing environmentally sustainable strategies in vulnerable locales adjoining the Beas waterway.

Keywords: Beas river; Microplastics; Policy implementation; Population size; Risk assessment; Western Himalayas.