Keywords: 
• microplastics /
• water environment /
• ecological effects /
• toxicity

Abstract: Plastics are widely used in our daily life, which would enter rivers, lakes, offshore, deep sea, oceans, and even polar regions eventually under a variety of environmental effects if they are thrown away. Under the effects of external conditions, such as high temperature, weathering and ultraviolet rays, the structural integrity of large plastics would be destroyed easily and decomposed into tiny bits of plastic, which are described as microplastics when their particle sizes are less than 5 mm. Some additives in the plastics, such as nonylphenol (NP), polybrominated diphenyl ethers (PBDEs), phthalates (PAEs) and bisphenol A (BPA), would release into the water environment during the degradation process of plastics, which threaten the safety of aquatic ecosystems. Microplastics are easily eaten by zooplankton or transferred through the aquatic food chain, which would result in their accumulation in living organisms, and cause an irreversible toxic effect on the organisms. Additionally, microplastics could serve as a carrier of some chemical contaminants due to their structural characteristics, resulting in stronger toxicity when they are combined with the contaminants. Thus, the safety of water environment is facing the threat of microplastics pollution, which has become a global environmental issue. This paper reviewed the sources, distribution, migration and transformation of microplastics, and their influences on water environment. And some solutions were proposed to solve the potential pollution of microplastics in water environment. It is hoped that the results will provide theoretical basis and data support to the research of microplastics and their ecological effects on water environment.