Sources of Microplastic in the Environment

Abstract

Generally, microplastics (MPs) in the environment come from two main types of source, which lead to different sizes of plastic particles: one is the primary source, and another is the secondary source. However, it is not easy or even impossible to identify the exact source of MPs detected in the environment. Primary sources of environmental MPs include plastic pellets, personal care products containing microbeads, paint, washing wastewater, sewage sludge, plastic running tracks in schools, artificial turf, rubber road in cities, and vehicle tire wear. Meanwhile, secondary sources include municipal debris such as plastic bags and bottles, fishing wastes, farming film, and other large size plastic wastes. Among these sources, vehicle tire wear is regarded as one of the most important sources of environmental microplastic due to the rapid global increase in the number of vehicles. However, available studies about the presence of rubber particles in the environment are very scarce. It is estimated that secondary sources of MPs currently account for the dominant of MPs in the environment although large plastic wastes need hundreds of years to break down into MPs under natural conditions. The appropriate management of plastic wastes and wastewater is the crucial step to prevent and control microplastic pollution in the environment in the future.