Overview
- A Columbia–UC Berkeley team reported in Nature that micro- and nanoplastic surfaces activate nearby water to form reactive oxygen species, including highly reactive hydroxyl radicals.
- Laboratory tests showed that plastics varied in activity, with polyethylene and polypropylene producing the most reactive species and PMMA producing far less.
- When mouse red blood cells were exposed to those lab-generated particles the cells deformed and ruptured, and the extent of hemolysis tracked with the amount of reactive oxygen produced.
- The experiments used fresh, laboratory-made particles and the authors stress key limits: weathered environmental particles showed weaker activity, measuring real-world exposures is difficult, and the study does not prove these reactions cause human disease.
- The finding that the surfactant Triton X100 eliminated reactive oxygen in tests has led researchers to explore surface treatments and less-hydrophobic polymers, and it has already triggered new toxicology studies, exposure-measurement efforts and interest from federal research programs and the EPA.