All the trash we keep dumping into the ocean has finally come back to haunt us. According to a recent study, scientists have found unusually high amounts of tiny plastic particles, known as microplastics, in table sea salt. Although these tiny plastic particles were found in salt originating in China, experts warn this is most probably more widespread and could pose a threat to human health.

Salt is one of the most abundant elements on Earth and can be found in oceans, rocks, and even deep underneath the Earth’s surface. For a study, now published in the online journal Environmental Science and Technology, a team of researchers collected 15 brands of sea salt, lake salts, and rock/well salts sold at supermarkets throughout China. The scientists were specifically looking for the presence of microplastics, the tiny plastic particles left over in various human products, such as plastic bottles and bags. These microplastics are usually no larger than 5 millimeters in size, but they're believed to pose both environmental and human health risks. According to lead researcher Shi Huahong of the university’s Institute of Estuarine, “Microplastics are a particular threat to organisms due to their small size and their capacity to absorb persistent organic pollutants,” Quartz reported.

Results of the analysis revealed high amounts of these microplastics in the common table salt. However, the largest amount was found in sea salt, with around 1,200 plastic particles per pound. The researchers calculated that an individual consuming these contaminated sea salts at the recommended levels would ingest about 1,000 plastic particles each year. Although it's not clear yet whether or not consuming such large amounts of microplastics can have an adverse affect on human health, Richard Thompson, a professor of marine science and engineering at Plymouth University in the UK who coined the term “microplastics” in 2004, told Environmental Health Perspectives that these findings are still a “cause for concern.”

For now, the microplastics were only found in table salt sold in Chinese food stores, but experts agree that this problem is probably more widespread. “Plastics have become such a ubiquitous contaminant, I doubt it matters whether you look for plastic in sea salt on Chinese or American supermarket shelves,” Sherri Mason, an environmental science researcher at the State University of New York Fredonia told Scientific American.

In addition, China is the world’s largest salt producer. This means that individuals living thousands of miles away from the source are likely to still be affected by this problem. The American government has recently taken steps to reduce the amount of microplastics that end up in waterways. In 2014, New York state lawmakers proposed a ban on cosmetics that contain microbeads, due to the toll these tiny plastic balls had taken on the environment. Although the ban has yet to be confirmed, the push has helped bring attention to this ongoing international problem.

Source: Yang D, Shi H, Li J, Jabeen K, Kolandasamy P. Microplastic pollution in table salts from China. Environmental Science & Technology. 2015.