TY - JOUR

T1 - Genotoxicity of Particles From Grinded Plastic Items in Caco-2 and HepG2 Cells

AU - Roursgaard, Martin

AU - Hezareh Rothmann, Monika

AU - Schulte, Juliane

AU - Karadimou, Ioanna

AU - Marinelli, Elena

AU - Møller, Peter

PY - 2022

Y1 - 2022

N2 - Large plastic litters degrade in the environment to micro- and nanoplastics, which may then enter the food chain and lead to human exposure by ingestion. The present study explored ways to obtain nanoplastic particles from real-life food containers. The first set of experiments gave rise to polypropylene nanoplastic suspensions with a hydrodynamic particle size range between 100 and 600 nm, whereas the same grinding process of polyethylene terephthalate (PET) produced suspensions of particles with a primary size between 100 and 300 nm. The exposure did not cause cytotoxicity measured by the lactate dehydrogenase (LDH) and water soluble tetrazolium 1 (WST-1) assays in Caco-2 and HepG2 cells. Nanoplastics of transparent PET food containers produced a modest concentration-dependent increase in DNA strand breaks, measured by the alkaline comet assay [net induction of 0.28 lesions/10(6) bp at the highest concentration (95% CI: 0.04; 0.51 lesions/10(6) base pair)]. The exposure to nanoplastics from transparent polypropylene food containers was also positively associated with DNA strand breaks [i.e., net induction of 0.10 lesions/10(6) base pair (95% CI: -0.04; 0.23 lesions/10(6) base pair)] at the highest concentration. Nanoplastics from grinding of black colored PET food containers demonstrated no effect on HepG2 and Caco-2 cells in terms of cytotoxicity, reactive oxygen species production or changes in cell cycle distribution. The net induction of DNA strand breaks was 0.43 lesions/10(6) bp (95% CI: 0.09; 0.78 lesions/10(6) bp) at the highest concentration of nanoplastics from black PET food containers. Collectively, the results indicate that exposure to nanoplastics from real-life consumer products can cause genotoxicity in cell cultures.

AB - Large plastic litters degrade in the environment to micro- and nanoplastics, which may then enter the food chain and lead to human exposure by ingestion. The present study explored ways to obtain nanoplastic particles from real-life food containers. The first set of experiments gave rise to polypropylene nanoplastic suspensions with a hydrodynamic particle size range between 100 and 600 nm, whereas the same grinding process of polyethylene terephthalate (PET) produced suspensions of particles with a primary size between 100 and 300 nm. The exposure did not cause cytotoxicity measured by the lactate dehydrogenase (LDH) and water soluble tetrazolium 1 (WST-1) assays in Caco-2 and HepG2 cells. Nanoplastics of transparent PET food containers produced a modest concentration-dependent increase in DNA strand breaks, measured by the alkaline comet assay [net induction of 0.28 lesions/10(6) bp at the highest concentration (95% CI: 0.04; 0.51 lesions/10(6) base pair)]. The exposure to nanoplastics from transparent polypropylene food containers was also positively associated with DNA strand breaks [i.e., net induction of 0.10 lesions/10(6) base pair (95% CI: -0.04; 0.23 lesions/10(6) base pair)] at the highest concentration. Nanoplastics from grinding of black colored PET food containers demonstrated no effect on HepG2 and Caco-2 cells in terms of cytotoxicity, reactive oxygen species production or changes in cell cycle distribution. The net induction of DNA strand breaks was 0.43 lesions/10(6) bp (95% CI: 0.09; 0.78 lesions/10(6) bp) at the highest concentration of nanoplastics from black PET food containers. Collectively, the results indicate that exposure to nanoplastics from real-life consumer products can cause genotoxicity in cell cultures.

KW - nanoparticles

KW - microplastic

KW - oxidative stress

KW - DNA damage

KW - comet assay

KW - OXIDATIVELY DAMAGED DNA

KW - ADHESION MOLECULE EXPRESSION

KW - DIESEL EXHAUST PARTICLE

KW - LUNG EPITHELIAL-CELLS

KW - COMET ASSAY

KW - PULMONARY EXPOSURE

KW - TELOMERE LENGTH

KW - ANIMAL-MODELS

KW - MICROPLASTICS

KW - TOXICITY

U2 - 10.3389/fpubh.2022.906430

DO - 10.3389/fpubh.2022.906430

M3 - Journal article

C2 - 35875006

VL - 10

JO - Frontiers in Public Health

JF - Frontiers in Public Health

SN - 2296-2565

M1 - 906430

ER -