Micro-Nanoplastics from Stormwater Runoffs to Water Bodies: An In-Depth Investigation

Although plastic, due to its durability, low cost, and versatility, has contributed to the development of society and has made people’s lives convenient, its drastic increase in manufacturing and production with limited measures for its management and disposal has led to a substantial accumulation in the environment. Due to its universal distribution, plastic is acknowledged as a global problem. More than half a century ago, scientists stated the existence of minute plastic elements in oceans, and since then, numerous studies have documented evidence of microplastics (MPs) and nanoplastics (NPs) in diverse ecosystems including terrestrial, atmospheric, aquatic, and biota. As per the US National Oceanic and Atmospheric Administration, MPs measure <5 mm in diameter, whereas NPs are <100 μm in diameter. Over the last decade, the increasing concentration of MPs and NPs in aquatic ecosystems is documented as a serious environmental issue. Stormwater is known to be a key contributor to MP and NP pollution in the aquatic ecosystem, as it does not undergo any treatment before entering the aquatic environment and levels of pollutants in stormwater are not regulated. The prominent sources of MPs and NPs in stormwater are tire and road wear particles, single-use plastic products, and wastewater treatment plant effluents. These MPs and NPs are taken up by the organisms and get accumulated in the biota; these small particles can also enter the roots of plants and enter the food web. Although many steps have been taken by regional, national, and international regulatory bodies, these appear to be ineffective in curbing plastic pollution on a large scale. Management and preventive strategies need to be undertaken along with consumer awareness programs and the development of waste management infrastructure.