Is Japan at low risk for PFAS immunotoxicity?: human biomonitoring study in contaminated areas in Japan.

Background: Per- and polyfluoroalkyl substances (PFAS) are now considered global contaminants posing health risks. Recent human biomonitoring data in Japan are presented.

Methods: Human biomonitoring data from Japan, dating back to 2000, were reviewed. In addition, 399 serum samples collected in a primary care clinic in Urayasu City, Okinawa Island-one of the highest PFAS-exposed areas in Japan-between 2021 and 2022 were analyzed. Serum levels of four PFAS were compared with risk levels based on the assessment by Sonne et al. and the European Food Safety Agency.

Results: The PFAS levels in the general population from various areas other than Hokkaido (16.1-43.5 ng/mL) are classified at moderate to severe risk for immunotoxicity based on the assessment.

Conclusions: A portion of the Japanese population has had high exposure to PFAS and was at high risk of immunotoxicity, and this situation remained in PFAS-contaminated areas in the 2020s.