Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2021 Jul 20:779:146523.
doi: 10.1016/j.scitotenv.2021.146523. Epub 2021 Mar 18.

Cellular internalization and release of polystyrene microplastics and nanoplastics

Ling Liu  1 , Kexin Xu  1 , Bowen Zhang  1 , Yiyuan Ye  1 , Qiu Zhang  2 , Wei Jiang  3
Affiliations

Cellular internalization and release of polystyrene microplastics and nanoplastics

Ling Liu et al. Sci Total Environ. .

Abstract

Microplastics and nanoplastics can accumulate in organisms after being ingested, be transported in the food web, and ultimately threaten human health. An understanding of the cellular internalization and release of micro(nano)plastics is important to predict their cytotoxicity. In this study, 50 nm, 500 nm and 5 μm polystyrene particles (PS50, PS500 and PS5000) were exposed to both model cell membranes and rat basophilic leukemia (RBL-2H3) cells. PS50 and PS500 absorb on the model membrane due to hydrophobic interactions and Van der Waals' forces, and may also penetrate the model membrane. PS50 and PS500 are internalized into living cells via both passive membrane penetration and active endocytosis. The passive membrane penetration is due to the partition of polystyrene particles in the water-phospholipid system. The endocytosis of PS50 occurs through the clathrin-mediated pathway, the caveolin-mediated pathway and macropinocytosis, but endocytosis of PS500 is mainly via the macropinocytosis. PS5000 cannot adhere to the cell membrane or be internalized into cells due to its large size and weak Brownian motion. The endocytosed PS50 and PS500 mainly accumulate in the lysosomes. The passively internalized PS50 and PS500 initially distribute in the cytoplasm not in lysosomes, but are transported to lysosomes with energy supply. PS50 and PS500 are excreted from cells via energy-free penetration and energy-dependent lysosomal exocytosis. The masses of the internalized PS50 inside the cells and the excreted PS50 outside the cells were both higher than the masses of PS500, indicating that the smaller particles are more easily enter or leave cells than do their larger counterparts. Our findings will contribute to the risk assessment of micro(nano)plastics and their safe application.

Keywords: Endocytosis; Exocytosis; Microplastics; Nanoplastics; Passive membrane penetration.

PubMed Disclaimer

Conflict of interest statement

Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

LinkOut - more resources