Investigation of microplastic pollution in river Alaknanda stretch of Uttarakhand

Microplastic pollution research is conducted at a rapid rate throughout the world. However, microplastics (MPs) research in the freshwater ecosystem especially riverine ecosystem is lacking in India. This study is the pioneer to explore the occurrence of MPs in an Indian river. For the present investigation a stretch of river Alaknanda which is a major stream of river Ganga was selected. This stretch was divided into five sampling sites from which five water samples and four sediment samples were collected. The samples were filtered, oxidized, density separated and finally studied under compound microscope and Scanning Electron Microscope. Further, Energy-Dispersive X-ray Spectrum was also conducted to analyze the elemental status of the samples. The result of this research study recorded a total of 955 MPs. Among which 566 particles of the MPs were in water samples while 389 particles were found in sediment samples. In this study threads/fibers were the dominating type, i.e., 412 particles and particle size less than 1 mm was the most abundant type of MPs. Presence of such fine size of plastic particles increases the effect of exposure and interaction of particles with aquatic organisms and possesses a bigger threat for aquatic life. Metals like sodium, potassium, aluminum, calcium, titanium and magnesium were found attached with the MPs, indicating the potential risks to the living organisms.

Automated summary

Research on microplastic pollution is rapidly expanding worldwide, but is lacking in the freshwater ecosystem of India. This pioneering study in an Indian river found a total of 955 microplastic particles, with fibers being the dominant type and particles smaller than 1 mm being most abundant. The presence of these fine plastic particles poses a significant threat to aquatic life, as they were found to be attached with metals indicating potential risks to living organisms.