Comparative toxicity of microplastics obtained from human consumer products on human cell-based models

Area of Science:

• Environmental Science
• Toxicology
• Cell Biology

Background:

• Plastic waste is a global pollution issue, generating microplastics (MPs) through environmental degradation.
• While pristine polymer toxicity is studied, the health impacts of MPs from consumer products remain unclear.

Purpose of the Study:

• To investigate the cytotoxic and genotoxic effects of microplastics derived from single-use consumer plastics.
• To assess these effects across multiple human cell lines.

Main Methods:

• Cryo-milled single-use plastic products (fork and cup) were used to create microplastic samples.
• Eight cell lines (Caco-2, HEK001, MRC-5, HMEC-1, HepaRG, HMC-3, T47D) were exposed to microplastics at concentrations ranging from 0.01 to 100 μg/mL.
• Cell viability was assessed, and genotoxicity was evaluated using the comet assay.

Main Results:

• Microplastics from consumer plastics reduced cell viability in specific cell lines (HMEC-1, HMC-3, HepaRG) at higher concentrations (10-100 μg/mL).
• Plastic cup microplastics paradoxically increased proliferation in HMEC-1 cells.
• DNA fragmentation was elevated in HMEC-1 and HMC-3 cells upon exposure to both fork and cup microplastics.

Conclusions:

• Microplastics from consumer-grade plastics possess cytotoxic and genotoxic potential.
• Endothelial (HMEC-1) and microglial (HMC-3) cells appear particularly susceptible to these adverse effects.
• These findings underscore the potential health risks associated with microplastic exposure from everyday plastic items.