Uptake and effects of orally ingested polystyrene microplastic particles in vitro and in vivo
Evidence exists that humans are exposed to plastic microparticles via diet. Data on intestinal particle uptake and health-related effects resulting from microplastic exposure are scarce. Aim of the study was to analyze the uptake and effects of microplastic particles in human in vitro systems and in rodents in vivo. The gastrointestinal uptake of microplastics was studied in vitro using the human intestinal epithelial cell line Caco-2 and thereof-derived co-cultures mimicking intestinal M-cells and goblet cells. Different sizes of spherical fluorescent polystyrene (PS) particles (1, 4 and 10 µm) were used to study particle uptake and transport. A 28-days in vivo feeding study was conducted to analyze transport at the intestinal epithelium and oxidative stress response as a potential consequence of microplastic exposure. Male reporter gene mice were treated three times per week by oral gavage with a mixture of 1 µm (4.55 × 107 particles), 4 µm (4.55 × 107 particles) and 10 µm (1.49 × 106 particles) microplastics at a volume of 10 mL/kg/bw. Effects of particles on macrophage polarization were investigated using the human cell line THP-1 to detect a possible impact on intestinal immune cells. Altogether, the results of the study demonstrate the cellular uptake of a minor fraction of particles. In vivo data show the absence of histologically detectable lesions and inflammatory responses. The particles did not interfere with the differentiation and activation of the human macrophage model. The present results suggest that oral exposure to PS microplastic particles under the chosen experimental conditions does not pose relevant acute health risks to mammals.
KeywordsMicroplastic Oral uptake Particle size Gastrointestinal barrier HOTT mice
The authors thank Anja Köllner and Beatrice Rosskopp for technical assistance. This work was supported by the German Federal Institute for Risk Assessment (Projects 1322-675, 1322-622 and 1323-102).
Compliance with ethical standards
Conflict of interest
We declare no conflict of interest.
- Canesi L, Ciacci C, Bergami E, Monopoli MP, Dawson KA, Papa S et al (2015) Evidence for immunomodulation and apoptotic processes induced by cationic polystyrene nanoparticles in the hemocytes of the marine bivalve mytilus. Mar Environ Res 111:34–40. https://doi.org/10.1016/j.marenvres.2015.06.008 CrossRefPubMedGoogle Scholar
- Della Torre C, Bergami E, Salvati A, Faleri C, Cirino P, Dawson KA et al (2014) Accumulation and embryotoxicity of polystyrene nanoparticles at early stage of development of sea urchin embryos Paracentrotus lividus. Environ Sci Technol 48:12302–12311. https://doi.org/10.1021/es502569w (5260196) CrossRefPubMedGoogle Scholar
- des Rieux A, Fievez V, Theate I, Mast J, Preat V, Schneider YJ (2007) An improved in vitro model of human intestinal follicle-associated epithelium to study nanoparticle transport by m cells. Eur J Pharm Sci 30:380–391. https://doi.org/10.1016/j.ejps.2006.12.006 (17291730) CrossRefPubMedGoogle Scholar
- Jani P, Halbert GW, Langridge J, Florence AT (1989) The uptake and translocation of latex nanospheres and microspheres after oral administration to rats. J Pharm Pharmacol 41:809–812. https://doi.org/10.1111/j.2042-7158.1989.tb06377.x (2576440) CrossRefPubMedGoogle Scholar
- Koeppen BM, Stanton BA (2017) Functional anatomy and general principles of regulation in the gastrointestinal tract. In: Koeppen BM, Stanton BA (eds) Berne & levy physiology, vol 7. Elsevier Health Sciences, Oxford, p 511Google Scholar
- Lichtenstein D, Ebmeyer J, Knappe P, Juling S, Bohmert L, Selve S et al (2015) Impact of food components during in vitro digestion of silver nanoparticles on cellular uptake and cytotoxicity in intestinal cells. Biol Chem 396:1255–1264. https://doi.org/10.1515/hsz-2015-0145 (26040006) CrossRefPubMedGoogle Scholar
- PlasticsEurope (2016) Plastics—the facts 2016: an analysis of European plastics production, demand and waste data. Accessed 22 Jan 2018Google Scholar
- Rochman CM, Kurobe T, Flores I, Teh SJ (2014) Early warning signs of endocrine disruption in adult fish from the ingestion of polyethylene with and without sorbed chemical pollutants from the marine environment. Sci Total Environ 493:656–661. https://doi.org/10.1016/j.scitotenv.2014.06.051 (24995635) CrossRefPubMedGoogle Scholar
- Tsuchiya S, Kobayashi Y, Goto Y, Okumura H, Nakae S, Konno T et al (1982) Induction of maturation in cultured human monocytic leukemia cells by a phorbol diester. Can Res 42:1530–1536Google Scholar
- Walczak AP, Hendriksen PJ, Woutersen RA, van der Zande M, Undas AK, Helsdingen R et al (2015) Bioavailability and biodistribution of differently charged polystyrene nanoparticles upon oral exposure in rats. J Nanoparticle Res Interdiscip Forum Nanoscale Sci Technol 17:231. https://doi.org/10.1007/s11051-015-3029-y (PMC4440892) CrossRefGoogle Scholar