Environmental forensic analysis of the microplastic pollution at Nattika Beach, Kerala Coast, India

Kerala, being a prominent tourist destination in the southern part of India with a coastline of 560 km, is prone to microplastic pollution. The National Oceanic and Atmospheric Administration (NOAA) of the USA defines microplastics as plastics of size < 5 mm-1 nm. To solve the problem of microplastic pollution, it is essential to track its source. As plastics are pervasive, it is challenging to track its source with a level of certainty required for implementing control strategies. Formulating and adopting suitable environmental forensic techniques to track microplastic pollution become important in this context. This study quantified the microplastic pollution of the Nattika coast, Kerala, India, and devised an environmental forensic investigation strategy for identifying the pathways and sources of microplastics. The microplastics of size 5-1 mm only were considered. The number of microplastics found in the Nattika Beach in 2017 and 2018 was 70.15 items kg(-1) of sand and 120.85 items kg(-1) of sand, respectively. The microplastics were subjected to analysis in FTIR and SEM as part of characterization. The forensic investigation of the pollution indicated that majority of the microplastic is sourced from the site/nearby area. The investigation could draw useful conclusions regarding the pathways of pollution. The fibrous microplastic, a significant component in the sample, was found to be sourced from the fishing net mending activities carried out close to the shore.