A comparative review of microplastics and nanoplastics: Toxicity hazards on digestive, reproductive and nervous system

Due to its excellent physical and chemical properties and low price, plastic has replaced part of the use of stone, wood and metal. The inability to degrade and improper handling have caused plastic pollution to become one of the most serious environmental problems in the world today. Plastic fragments undergo ultraviolet radiation, natural weathering, and biodegradation to form microplastics (MPs) and nanoplastics (NPs)1. The current re-search on MPs mainly focuses on transportation, bioaccumulation and toxicity. However, existing reviews treat NPs and MPs as a whole to discuss toxic damage, and ignore their differences in toxicity. In this review, we pro-vided the latest research information on the differences in toxicity between MPs and NPs in the digestive system, reproductive system and nervous system, and explored the possible reasons for differences in toxicity for the first time. Finally, it is recommended to consider the influence of microplastics components on the differences in tox-icity, as most of the researches now focuses on a few types of microplastics. And it is necessary to study the unique toxicity mechanism of MPs/NPs in bioaccumulation and pathway activation from the differences in phys-ical properties. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

Plastic, with its excellent physical and chemical properties and low cost, has replaced some of the traditional materials like stone, wood, and metal, but improper handling and the inability to degrade have led to it becoming a serious environmental issue. Current research on microplastics focuses on transport, bioaccumulation, and toxicity, with a common approach treating microplastics and nanoplastics as a whole, overlooking their differences in toxicity.