The exposure routes, organ damage and related mechanism of the microplastics on the mammal

Microplastics widely exist in the atmosphere, soil and water environment, causing extensive attention to their adverse effects on human health. We here systematically recapitulated the exposure routes of microplastics for human body and the consequent toxic effects on human organs. The exposure routes include digestive tract, respiratory tract and skin, particularly digestive tract. It has been revealed that intestinal tract, liver and kidney are the main enrichment sites of microplastics, leading to intestinal flora imbalance, intestinal function disorder and liver lipid metabolism disorder. However, the toxic effects on other tissues and systems, such as lung, kidney, nervous system and reproductive system, warrant more studies.The underlying toxic mechanisms of microplastics mainly include oxidative stress and inflammatory response. The current review would help advance the systematical understand on the health hazards of microplastics, and provide support for the risk assessment of microplastics in the future.