A Brief Review on Microplastic Pollution in Aquatic Body

College of Engineering & Management Kolaghat, Kolaghat, India

E-mail: sharmisthabose@cemk.ac.in

The extent of mocroplastics in water body is a recent challenge in the field of environment. The issue has become aggravated particularly after COVID-19 due to the excessive use of plastic PPEs including face masks, gloves as per Government and WHO instructions.  COVID-19 pandemic also caused a spike in the demand for home delivery packaged vegetables, groceries and many necessary items. This not only resulted in increased consumption of plastic materials but also generated huge amount of  plastic waste. These plastic particles enter the aquatic system through different routes like effluent discharge from waste water treatment plants, rain water runoff, agricultural runoff, direct littering, and eventually reach the ocean via rivers and sea. Thus ocean basins become the ultimate sink for microplastics. The widespread transport of microplastics on land and aquatic medium is due to their physical characteristics like shape, small size and low density. At the same time, the durability, stability, slow degradation kinetics, long residence time in aquatic body, high ratio of surface area to volume, ability to adsorb toxic materials from surroundings and subsequent release of the materials in aquatic media make the microplastics a potent vector of different diseases. Microplastics may induce different detrimental effects on aquatic organisms which include embryotoxicity, neurotoxicity, behavioral changes, biochemical and hematological changes. Owing to the size similarity with plankton, microplastics are ingested by aquatic organisms of different tropic levels and ultimately enters into the human body through food chain. The entry of micrplastics with food can also pose a significant effects on human body. Major sources of microplastics in human body are table salts, drinking water and sea food. Thus microplastics may risk not only aquatic organisms but also can be a threat of human life. It is seen from several studies that biological effects of microorganisms depend on shape, size, composition and physical characteristics of microplastics. Therefore control of microplastics in aquatic body is very much needed. Conventional primary and secondary treatments can remove major portion of microplastics but incorporation of advanced treatment processes increases the overall removal efficiency. However, complete removal of microplastics in final discharge of waste water treatment plant is still awaited and also microplastics removed from the waste water treatment plant often return to the environment through sludge. This invites more study and research wok in this area. This paper presents a brief discussion on the 1) sources of microplastics in aquatic body, 2) toxicity of microplastics on aquatic organisms, 3) a summary of different methods reported to remove microplastics from aquatic body.