When Japan began releasing treated wastewater from the Fukushima Daiichi nuclear power plant into the Pacific Ocean, there were numerous news reports (for example, here, here and here) and social media posts (here, here, here and here) about people panic-buying iodized salt in China, Hong Kong, Taiwan, and South Korea.
Photos and videos showing consumers rushing to hoard salt from store shelves were widely shared with comments pointing out the belief that salt is an antidote to radiation and a fear that “safe” salt might soon run out, both of which are false.
Iodized salt is not an antidote to radiation
One of the reasons why many people buy iodized table salt in Asia seems to be because they wrongly believe it works like potassium iodide (KI) tablets and pills that are used to protect the body from some radiation.
When inhaled or ingested, radioactive material in our body can increase the risk of thyroid cancer. According to the World Health Organization, iodine tablets fill up the thyroid with potassium iodide, preventing harmful radioactive iodine from getting in.
But WHO also says iodized table salt “does not contain sufficient concentrations of iodine to block the uptake of radioactive iodine by the thyroid.”
“During nuclear emergencies, iodized table salt should not be used as a substitute for KI since it will not provide protection against radioactive iodine, and because eating excessive amounts of iodized salt will itself pose a significant health hazard,” the WHO explains in its website.
The Center for Food and Safety (CFS) in Hong Kong also said there was no scientific evidence showing iodized salt or other iodine-rich food would protect the body from the effects of radiation.
Excessive consumption, however, is harmful, particularly to people suffering from hypertension, and heart or kidney diseases, according to CFS’s public announcement.
Persistent misbelief in China
The panic-buying of salt was also widely reported in China 12 years ago during the Fukushima nuclear crisis in March 2011.
The article also quoted a researcher from the Chinese Center for Disease Control and Prevention, saying that excessive iodine consumption would be “harmful.”
We found a 2016 report by the Chinese Society for Environmental Sciences that investigated people’s rationale behind hoarding by polling more than 3,100 citizens in Beijing, Hubei and Gansu.
The research concluded the “low” health and environmental science literacy among more than 90% of the participants could be the main reason.
Another possible reason for stockpiling table salt was a rumor that Shandong waters were polluted with radiation due to the Fukushima accident. Later, the man who made the false claim in online chatrooms was reportedly detained for ten days as a result.
The panic-buying eventually eased in China in 2011 as radiation from the nuclear plant did not pose much of an effect on sea salt deposits, nor was there a table salt shortage.
However, the same claims and similar fears circulated widely in the country 12 years later. China’s National Salt Industry Group recently tried to appease such fears by saying that sea salt only made up 10% of China’s salt supplies, while the rest comes from local rock and lake salt.
Sourcing and supply of salt
In Hong Kong, salt from Japan accounts for less than one percent of the total sold in the city. The rest are imported from mainland China, Malaysia and Australia, according to the Census and Statistics Department.
Most Taiwanese table salt comes from its nearby seawater, according to the island’s Taiyen Biotech. It also says Taiwan has enough supplies to meet the 100,000-ton annual demand. The Taiwanese market also sources rock salt, rose salt, mineral salt and lake salt from Spain, Germany, the United Kingdom, and Turkey.
In South Korea, the Ministry of Oceans and Fisheries said it released an additional 400 tons of government reserve sea salt to the market since Aug.10 and would continue to do so until Sept. 27 to meet public demand.
Salt supplies have also been affected recently in South Korea due to inclement weather. Aside from domestically produced salt, government data shows South Korea also imported edible salt from Bolivia, mainland China, and the United States.
Controversy over water release
The amount of misinformation about the treated wastewater increased dramatically as Japan started the 30-year plan to release it to the Pacific Ocean.
The International Atomic Energy Agency said in a report that this move “will have a negligible radiological impact on people and the environment,” while environmental group Greenpeace raised questions about its safety, saying there were other options besides releasing the treated wastewater into the sea.
In a recent survey, Taiwanese authorities said they found “no abnormal radiation” in coastal areas from the 107 monitoring points.
In South Korea, the Ministry of Oceans and Fisheries inspected 82 salt fields from April to August and detected no radiative element. It also pledged to inspect all of the country’s 837 salt fields, including 687 small and medium-sized salt fields from outsourced entities.