Occurrence, distribution, characteristics, toxicity, human health effects and removal techniques of Microplastic: A Review

Since the inception of commercial plastic production around 1950, modern society's reliance on plastics has surged dramatically. This growing dependence is attributed to the remarkable advantages of plastics, including their versatility, stability, lightweight nature, and cost-effectiveness, all of which have propelled their global demand to unprecedented levels. These materials find applications in packaging, construction, electronics, textiles, medical devices, and more, owing to their capacity to be moulded into a wide array of shapes and sizes. Regrettably, the prevalent pattern involves utilizing plastics briefly before discarding them on land, exacerbating environmental and sustainability challenges. However, the disposability of plastics after single-use applications has led to the generation of microplastics (MPs), an emerging class of contaminants, in our environment. MPs are plastic particles less than 5 mm in size and could originate due to primary and secondary sources. MPs size range which are generated as such are the primary ones while the secondary MPs are a result of fragmentation of larger plastic particles which eventually enters the aquatic, terrestrial, atmospheric environments and human consumables affecting human health a lot. MPs have been found in biological samples such as faeces, sputum, saliva, blood and placenta. Cancer, intestinal, pulmonary, cardiovascular, infectious and inflammatory diseases are induced or mediated by microplastics. Overcoming these issues necessitates collaborative efforts to innovate, regulate, and raise awareness, ultimately steering society towards a more sustainable relationship with plastics starting with prevention, followed by reducing, reusing, recycling, recovering, and ending with disposal as the least preferable option. This study seeks to, review the sources, formation, occurrence, toxicity, effects of microplastics on the environment and human health, and remediation methods of microplastics (like coagulation, membrane bioreactors, sand filtration, adsorption, photocatalytic degradation, electrocoagulation and magnetic separation) and comprehensively examine scientific literature pertaining to microplastic research across various environmental domains.