A new study has focused on the characteristics of sea salt, rock salt, and lake salt from around the world. And the conclusions are alarming, they contain microplastics.
It is not news that sea salt contains microplastics, this has been known for years. But it remained to be clarified to what extent they were spread in this condiment of daily use on tables around the world.
The South Korea and Greenpeace East Asia team was in charge of analyzing 39 commercial brands of salt, of which they determined that 36 contained microplastics. This means that 90% of the table salt brands tested globally are contaminated.
"Findings suggest that human ingestion of microplastics through marine products is highly linked to emissions in any given region"reported Seung-Kyu Kim, a professor of marine science at Incheon National University in South Korea.
The salt samples were taken from 21 countries in Europe, South and North America, Africa and Asia. The three brands that did not contain microplastics come from Taiwan (refined sea salt), China (refined rock salt) and France (unrefined sea salt produced by solar evaporation).
The salt brands with the highest density of microplastics were those from Asia and those with the highest amounts were from Indonesia.
This country, with 54,720 kilometers of coastline, is one of the countries that suffers the most from plastic pollution in the world.
Are microplastics harmful?
The new study estimates that the average adult consumes approximately2,000 microplastics per year only through the intake of salt.
From 60 to 280 microparticles per kilo of salt were discovered in all the types of salt studied by the University of Alicante, which means that each Spaniard ingests 510 plastic microparticles per year just for seasoning their food, as long as they respect the limit recommended by the World Health Organization.
But it is not yet clear whether microplastics are harmful because there is insufficient information to corroborate it.
Existing studies examined different types of microplastics, including microspheres, fragments and fibers, causing a data "mismatch" that makes comparisons similar to comparing "apples to pears," Alistair Boxall, professor of geography, said in a statement. from the University of York and co-author of the study.
"Based on our analysis, currently the evidence to suggest that microplastics cause significant adverse effects is limited," he says. "More quality and more global monitoring studies are urgently needed alongside more realistic environmental effect studies on particle size and types of materials present in the environment."
The study can be seen complete in Environmental Science & Technology.
With information from: