Changes in Microplastic and Associated Elemental Constituents Across Different Rice Farming Systems in North East India

Global plastic use has surged, generating 20-90 million tons of waste annually, which breaks down into microplastics that contaminate environments. While marine microplastic pollution has been widely studied, research on agroecosystems, particularly paddy soil, remains limited. This study assessed microplastic pollution across four types of agricultural land use in the Cachar district: boro rice cultivation, rainfed rice cultivation, upland rice cultivation, and natural forests. Boro rice soil exhibited the highest contamination (213 particles per 100 g of soil), while natural forests had the lowest (98 particles per 100 g of soil). Two primary types of microplastics were found; fibers (89.86%) and fragments (10.14%). Most microplastics were smaller than 500 μm (67.79%), while only 7.83% were larger than 1 mm. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) analyses revealed smoother microplastics in forests and coarser ones in agricultural soils. EDX detected elements such as carbon, oxygen, aluminium, silicon, copper, sulphur, bromine, and molybdenum. This study offers vital baseline data for managing plastic waste and mitigating environmental and health risks.