Japan will launch a study on the health impact of potentially harmful chemicals known as PFAS, a government source said Monday, after their detection across the country fueled concern among local residents.
PFAS, or polyfluoroalkyl substances, used in various products such as frying pan coatings and water-repellent clothing, have been detected in high concentrations at places near Self-Defense Forces and U.S military bases as well as industrial areas.
With some researchers warning of adverse effects on the human body including an increased risk of cancer, the study, planned for three years from around June, will be conducted by three institutions.
In the study, Hokkaido University will use data on concentration levels of 39 kinds of PFAS contained in the blood of around 700 people from the fetal stage to late teens to examine the substances' impact on their fat metabolism and development, the source said.
Hyogo Medical University will conduct experiments on mice to probe whether the substances suppress the immune system and reduce the effectiveness of vaccinations, while the National Institute of Health Sciences will seek to elucidate the mechanism of their toxicity at the molecular level, it said.
PFAS is a general term for a group of over 10,000 artificial chemicals that include PFOS, or perfluorooctanesulfonic acid, and PFOA, or perfluorooctanoic acid.
Japan banned in principle the manufacturing and import of PFOS substances, commonly used in foam extinguishers, in 2018 for all applications, as well as those categorized as PFOA in 2021. Perfluorohexane sulfonic acid, or PFHxS, was added to the list in 2023.
The government-led study comes as 12 local assemblies across eight prefectures urged the Diet to take action to address the contamination after high concentration levels of PFAS were detected in recent years in various parts of the country.
Levels exceeding the government standard were reported near Yokota Air Base in western Tokyo and the U.S. Navy base in Yokosuka, southwest of Tokyo, as well as in a drainage channel in an industrial park in Fukushima Prefecture and areas surrounding a chemical factory in Shizuoka Prefecture.
PFAS are described as persistent organic pollutants, or forever chemicals, because they are nearly indestructible. As they do not degrade over time unlike most other chemicals, they can accumulate in the environment and the human body.
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