Scientific American, 10 March 2025

Microplastics Are Messing with Photosynthesis in Plants

Microplastics can cut a plant’s ability to photosynthesize by up to 12 percent, new research shows.

Microplastics are now a ubiquitous part of our daily physical reality. These minuscule fragments of degrading plastic now suffuse our air, our soil, the food we eat and the water we drink. They’re being detected everywhere researchers look, from Antarctic sea ice to human brains.

As scientists develop a better idea of where microplastics are accumulating in the environment, they’re just beginning to understand how these pollutants affect one of the most essential and widespread kingdoms of life on Earth: plants. A new study, published on Monday in the Proceedings of the National Academy of Sciences USA, reveals how microplastics hinder photosynthesis across a wide range of plant species—including crucial food crops. “It’s really scary,” says Marcus Eriksen, a marine scientist at the 5 Gyres Institute, a nonprofit plastic pollution research organization, who was not involved in the study.