Washington Post [unpaywalled]: “Microplastics have popped up in rivers, oceans, soil, food, tea and even Antarctic snow — and now these tiny plastic particles are showing up in clouds. A group of researchers from Waseda University in Tokyo recently found microplastics in the clouds above Mount Fuji. In a paper published in Environmental Chemistry Letters, the researchers wrote that these airborne microplastics could influence cloud formation — and in turn the climate. Plastic is ubiquitous — humans have produced more than 8 billion tons of it — and less than 10 percent of it is recycled. Because plastic waste doesn’t break down easily, it can exist in the environment for hundreds of years, becoming smaller and smaller, and ending up in our food, our bodies and the environment. It’s still unclear exactly how harmful these tiny particles are to humans, but some of the chemicals in plastics are believed to interfere with reproduction, stress responses, immune response and development. Microplastics in oceans threaten marine life and birds, and while there’s been less research on mammals, the studies that have been done in rats and mice point to serious harms. The authors of the new study warn that the presence of microplastics in clouds may present a whole new set of problems, though…”