Tea is often considered to be a healthy drink option, but you probably never considered that your tea may actually actually contain billions of harmful microplastics. According to a new study in Environmental Science & Technology, some premium tea brands are packaged in plastic pouches with a silky quality, and these bags can break down into the tea.
Nathalie Tufenkji, a professor of chemical engineering at McGill University, and her team purchased four types of commercial loose leaf teas packaged in plastic bags, emptied out the leaves, then dunked the bags in glass vials with water heated to 95 degrees. The team then used electron microscopy to analyze the water samples and determined that a single plastic tea bag released around 11.6 billion microplastics and 3.1 billion nanoplastics.
Tufenkji told New Scientist that this number is quite high compared to other foods that contain microplastics. “Table salt,” she said, “which has a relatively high microplastic content, has been reported to contain approximately 0.005 micrograms plastic per gram salt. A cup of tea contains thousands of times greater mass of plastic, at 16 micrograms per cup.”
After conducting several control experiments using cut tea bags with the leaves emptied out (so that any microplastics present in the tea leaves themselves didn’t affect the study), they found that particles are still released even when the tea bags remain uncut. While the 16 micrograms of plastics in one cup of tea don’t pose a dangerous risk to humans, long-term exposure could potentially be harmful. The study’s authors call for more research, and the need to further investigate the effect of microplastics on humans.