A study published Tuesday (Oct. 16) in the journal Environmental Science and Technology found microplastics in more than 90% of the packaged food-grade salt -- also known as table salt -- for sale in stores.
The team, from South Korea's Incheon National University and Greenpeace East Asia, sampled 39 brands of salt harvested in 21 countries and regions. Only three of the samples had no detectable1
Microplastics are virtually everywhere. Sea salt and lake salt are made by evaporating water and harvesting the salt that remains2
. Plastic waste flows from rivers into those bodies of water, so it's no surprise that the salt contains traces of it too. Scientists have been finding microplastics in salt for years, including in salt from countries and regions in Asia, Europe, and Africa.
But the latest study goes a step further, finding that looking at where the salt was produced is a good indicator3
of how much plastic pollution is coming from that particular region.
The 39 samples came from Australia, Belarus, Brazil, Bulgaria, Chinese mainland and Taiwan, Croatia, France, Germany, Hungary, India, Indonesia, Italy, Korea, Pakistan, Philippines, Senegal, Thailand, the UK, the US, and Vietnam.
Of these, 28 were sea salts, nine were rock salts, and two were lake salts.
Only three of the samples were microplastics-free: a refined sea salt from Taiwan, a refined rock salt from Chinese mainland, and an unrefined sea salt in France.