Taiwan Strengthens PFAS Regulation: PFOS and PFOA Banned from Groundwater Injection

On November 18, 2025, Taiwan’s Ministry of Environment announced a revision to its “Hazardous Substances Prohibited from Groundwater Injection” regulations, officially adding perfluoro octane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) to the list of substances banned from discharge into groundwater. This measure aims to strengthen the protection of water resources and public health given the persistent and hazardous nature of PFAS substances.

PFOS and PFOA Now Prohibited in Groundwater

• The Ministry of Environment cited the environmental persistence of PFAS and associated health risks as the key reasons for the regulatory update.
• According to the International Agency for Research on Cancer (IARC), PFOS is classified as a Group 2B possible carcinogen, while PFOA is classified as a Group 1 carcinogen.
• The revised regulation sets the allowable limit for PFOS and PFOA in wastewater injected into groundwater at non-detectable levels.

Legal Enforcement and Industry Responsibilities

• The Water Pollution Control Act already prohibits the injection of wastewater into groundwater.
• Any wastewater containing hazardous substances, including PFOS and PFOA, could result in criminal liability.
• The revision serves as a reference for regulatory enforcement and reinforces the principle of preventive protection for water resources.

Key Points for Industry and Public Awareness

• Taiwan is strengthening its environmental protection framework against persistent organic pollutants.
• PFAS chemicals, including PFOS and PFOA, are now officially banned from groundwater injection.
• Industries are urged to review their compliance and ensure that their wastewater does not contain any banned hazardous substances.
• Official documentation and details were made available on the Government Gazette website three days after the announcement.