“Scientists have found tiny plastic bits, known as microplastics, in salts collected from supermarkets across China. The researchers analyzed 15 brands of salt. They turned up plastic bits in table salt extracted from seas and lake water. They also found plastic bits in rock salt mined from underground deposits. By far, however, sea salt contained the most plastic. In a second study, the same team found similar plastic fibers in shellfish.
The new findings should, perhaps, come as no surprise. For years, studies have reported finding microplastics in ocean water. And in 2011, scientists showed that laundering clothes made of nylon and other types of plastic shed bits of lint. The wash water carried that lint down the drain and eventually into rivers and the ocean. Plastic bits have since turned up in sea animals. But the new paper is one of the first to report microplastics in food to be eaten by people.
It found that sea salt had 550 to 681 particles per kilogram (2.2 pounds). Each kilogram of lake salts had 43 to 364 particles. Rock salts had seven to 204 particles per kilogram.
These new data suggest that sea salt may be dragging microplastics from tainted water to dinner tables, the scientists conclude. They reported their findings October 20 in Environmental Science & Technology.
“We’re finding plastics in stranger and stranger places,” says Kara Lavender Law. She is an oceanographer at the Sea Education Association in Woods Hole, Mass., where she studies plastics in the ocean. Plastics, she notes, are “in salts, in the oceans, in the air. They’re all around us.” Law was not involved in the new study. But she says the findings may not be isolated to salt in China. Microplastics could taint sea salts from other regions, she warns. For now, no one knows what threat, if any, eating plastic bits might pose…”