PFAS Contamination Found in Hiroshima Drinking Water Wells

Hiroshima City has confirmed that groundwater used for drinking in part of the Asaminami area exceeds Japan’s PFAS guideline of 50ng/L, following a series of investigations triggered by local residents.

Background

In February 2026, a citizens’ group conducted water tests at their own expense on a drainage channel receiving effluent from the Kamiyasu industrial waste disposal site (unmarked on Google Maps) in Asaminami-ku. The results showed PFAS levels approximately six times higher than the national guideline value of 50ng/L.

Acting on the group’s findings, Hiroshima City carried out its own survey in March along the Aratani River — which flows from below the waste site through Kamiyasu to the Yasukawa River — and its tributaries. PFAS exceeding guideline values was detected at four locations. The highest reading was 1,400ng/L, 28 times the guideline. Even at the lowest sampling point, just before the river joins the Yasukawa [Google Map], the level was 160ng/L.

Despite the severity of the readings, city officials stated at the time that identifying the emission source “is not mandatory,” and indicated they would merely pass information to upstream businesses and ask them to consider possible responses.

Household Survey

Between April and May, the city surveyed groundwater usage at 302 households in the area around the Aratani River. Of these, 24 households were using the water for drinking or domestic purposes and underwent water quality testing.

Of the 10 households using the water for drinking, PFAS levels of up to 140ng/L were recorded — nearly three times the guideline. A further three households using groundwater for general domestic purposes recorded levels of up to 120ng/L.

Residents have been advised not to drink the water. However, the city has stated it has no plans to provide alternative water supplies or subsidise connection to the mains water network.

Ongoing Concerns

The situation at the Kamiyasu site goes beyond water contamination. A citizens’ group — 「上安産廃から安全安心を守る市民の会」(Citizens’ Association to Protect Safety and Security from the Kamiyasu Industrial Waste Site) — held a press conference at Hiroshima City Hall on June 3rd, alleging that forest clearance carried out during the establishment of the disposal site may have exceeded the legally permitted area, potentially in violation of the Forestry Act. The group called on the city to investigate and publish its findings.

The city responded that it would conduct an on-site inspection and interview the site operators within the month, and that replanting would be required if a violation is confirmed.
The city says it will expand its groundwater survey area and petition the national government for further action.

Source: RCC News [ja]