Camp Hansen is part of Marine Corps Base Camp Smedley D. Butler, which comprises all Marine Corps installations on Okinawa. (Keishi Koja/Stars and Stripes)
A town near a Marine Corps base on Okinawa discovered PFAS levels as much as four times higher than is permissible in Japan, according to annual survey results released Wednesday.
Kin town, near Camp Hansen, headquarters of the 31st Marine Expeditionary Unit, found elevated levels of PFAS in five of 14 sites sampled in September and November.
Three sites near the Ryukyu Hospital showed the highest PFAS levels, including 220 parts per trillion upstream of the hospital, 200 parts per trillion downstream and 130 parts per trillion where streams merged, according to the survey results.
The hospital is about 730 feet from Hansen’s southern fence line.
Japan’s water quality standard for PFAS is 50 parts per trillion. The U.S. Environmental Protection Agency sets no safe minimum standard for the organic compound.
PFAS — per- and polyfluoroalkyl substances — are manufactured chemicals widely used for waterproof and nonstick coatings and fire suppressants such as aqueous film-forming foams.
The firefighting foams are used by shipyards, military bases, chemical plants and refineries, according to the EPA’s website. U.S. Forces Japan in 2024 announced it had incinerated the last of its stockpiles of such firefighting foam.
PFAS and its component chemicals PFOA and PFOS are commonly referred to as “forever chemicals” because they persist in the environment. The American Cancer Society has linked PFAS exposure to an increased risk of tumors in the liver, breasts, testicles and pancreas.
“Ryukyu Hospital is close to Camp Hansen; we cannot deny the possibility that the contamination comes from the base,” a town spokesman said by phone Thursday. “The water is not used for drinking or domestic purposes.”
Marine Corps Installations Pacific by email Thursday referred questions from Stars and Stripes to Kin town.
The town began the annual water sampling for PFAS in 2019, according to the spokesman.
“We requested on base sampling in the past, but we were rejected, we are still considering what to do based on these results,” he said. Some Japanese government officials must speak to the press on condition of anonymity.
The prefecture has sought base access for water sampling four times since 2016, when elevated PFAS levels were first reported near U.S. bases. USFJ denied the requests in December, saying the evidence that its installations were sources of contamination was insufficient.
