Study Identifies Possible Microplastic-Water Reaction

A study published in Nature reports that microplastics generated reactive oxygen species when they met water in laboratory experiments, offering a possible mechanism for biological damage but not showing that the particles cause disease in people. Researchers from Columbia University and the University of California, Berkeley, tested several types of plastic in water. They found that reactions at the plastic-water boundary produced hydroxyl radicals, a form of reactive oxygen species. The study’s authors say these unstable molecules can damage biological material. The work was published October 14. The activity differed by plastic type. Polyethylene and polypropylene, which repel water more strongly, generated more radicals than plastics including PET and acrylic, according to the experiments. The researchers also reported that smaller plastic particles could expose more surface area to water, potentially increasing the opportunity for these reactions. In laboratory tests, the radicals damaged a protein and red blood cells from mice. In one experiment, a substance that neutralizes radicals reduced protein clumping, supporting the researchers’ conclusion that the radicals...