Microplastics in Salt and Shellfish????
The Atlantic Daily newsletter
Richard Macauley
| Oct 30, 2015
| Health
Scientists have discovered that various brands of table salt sold in China
contain a range of plastic pollution, which might make food unsafe.
The highest proportion of plastic was found in sea salt, according to a
paper from researchers at Shanghai’s East China Normal University. But even
salt from salt mines, briny lakes, and wells contained significant amounts.
“Microplastics are a particular threat to organisms due to their small size
and their capacity to absorb persistent organic pollutants,” said the
report, led by Shi Huahong of the university’s Institute of Estuarine and
Coastal Research and peer-reviewed in Environmental Science and Technology.
Shi and his colleagues discovered between 550 and 681 microplastic particles
per kilogram of table salt that originated from the ocean, 43 to 364 per
kilogram in lake salts, and 7 to 204 per kilogram in rock or well salts.
Here is a rather gruesome photograph of their findings:
Environmental Science and Technology
Although the oceans close to China appear to be a “hotspot” for microplastic
pollutants, it is unlikely Chinese table salt is the only salt that is
contaminated with plastics.
“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. “I’d like to see
some ‘me-too’ studies,” she added.
People who follow World Health Organization guidelines on salt intake (most
in the U.S. consume much more) would consume around 1,000 microparticles of
salt annually, Shi estimates. It’s not yet clear what kind of damage such
consumption could mean for humans—if it causes any damage at all. Regarding
the impact of microplastics on human health, Richard Thompson, a professor
of marine science and engineering at England’s Plymouth University, told the
Environmental Health Perspectives journal that “there are more questions
than answers.”
And indeed, other foods from the sea, such as shellfish, also contain
microplastics, but people concerned about plastic intake can just stop
eating those foods. The prevalence and necessity of salt in our diets makes
cutting out those microplastics much harder.
