Taiwan Strengthens Drinking Water Safety with New PFAS and Emerging Contaminant Guidelines

On 9 September 2025, Taiwan’s Ministry of Environment(MEO) reports that drinking water tests for PFAS (per- and polyfluoroalkyl substances) are compliant with national standards, and it has now issued guideline values for six additional emerging contaminants to strengthen water quality management. The new substances include germanium, thallium, boron, microcystin-LR, DEHP (a plasticizer), and the total sum of 20 PFAS compounds.

The Ministry revised the drinking water quality standards last November to include PFAS limits, becoming one of the first countries in Asia to implement such regulations. Under the new standards, PFOA + PFOS must not exceed 50 ng/L and PFOS + PFHxS must not exceed 70 ng/L. Since this year, testing has been conducted at 130 large-scale water treatment plants, covering 91% of the national water supply, with all results meeting the standards.

Analysis shows that over 96% of samples for PFOA + PFOS were either undetected or at less than a quarter of the standard, with only isolated cases in central Taiwan reaching about half the limit. For PFOS + PFHxS, 98% of samples were below a quarter of the limit, confirming that drinking water PFAS levels are generally safe nationwide. Surface water sources tend to have lower PFAS than groundwater, with the north, south, and eastern regions showing particularly low concentrations.

According to the Ministry, guideline values for emerging contaminants are updated continuously, following expert consultation and international trends such as the EU Drinking Water Directive. The new total PFAS guideline is 100 ng/L, and local environmental agencies and water utilities have been instructed to implement monitoring according to these values.

The Ministry also noted that future updates will follow international developments, with the National Environmental Research Institute enhancing testing methods and capacity, including total organofluorine screening techniques, to ensure Taiwan’s drinking water remains safe and aligned with global standards.