Japan's amended Water Supply Act imposes enforceable drinking water limits on per- and polyfluoroalkyl substances (PFAS) from April 2026, creating an immediate need for PFAS water testing standards aligned with the revised requirements. Restek has launched the PFAS-10 certified reference material (CRM) Mix, a single ready-to-use ampul containing ten linear PFAS compounds covering all analytes the Act requires and recommends.
How Has Japan's Water Supply Act Changed PFAS Testing Requirements?
The April 1, 2026 revision converts quarterly PFAS water testing from a voluntary practice to a mandatory obligation: water utilities must act when the combined concentration of perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) in tap water exceeds 50 ng/L. Japan's standard notification method classifies perfluorohexanesulfonic acid (PFHxS) as a recommended monitoring compound alongside PFOS and PFOA.
Sourcing individual component standards and blending calibration solutions from separate lots raises error risk and extends turnaround time; a single-ampul CRM that covers all targeted analytes directly reduces both. Restek formulated PFAS-10 in its ISO-accredited labs from materials greater than 99% pure. ¹⁹F NMR identifies isomers, LC-MS/MS quantifies trace PFAS impurities below 1%, and expanded data packs document that no off-target analytes affect quantitative results.
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PFAS-10 covers the analyte scope, purity standard, and documentation needs for compliant PFAS water testing programs:
- Ten Linear Compounds required and recommended under the Japan Water Supply Act (April 2026)
- Greater Than 99% Purity with isomers identified by ¹⁹F NMR; trace impurities quantified by LC-MS/MS below 1%
- Expanded Data Packs with lot-specific impurity profiles for every batch
- Verified Composition And Stability supporting long shelf life and consistent method development
- In Stock And Ready To Ship from Restek's certified reference material portfolio
PFAS-10 Applications: Drinking Water, Compliance, and Beyond
Beyond Japan Water Supply Act compliance, PFAS-10 suits any PFAS water testing program built around linear compound targets. The table below maps its ten-compound scope to key analytical workflows and geographic frameworks.
| Application Area | Relevance of PFAS-10 |
| Amended Water Supply Act Compliance (Japan) | Covers PFOS and PFOA (mandatory standards) and PFHxS (recommended study item), plus seven further linear compounds |
| Drinking Water and Wastewater Monitoring | Supports routine LC-MS/MS quantification for regulatory compliance programs |
| PFAS Method Development | Enables multi-analyte calibration from a single preparation step |
| Asia-Pacific Environmental Programs | Applicable to regional monitoring frameworks sharing linear PFAS target lists with Japan's revised standards |
PFAS-10 joins a growing Restek portfolio that includes single-component standards and method-specific mixes for EPA Methods 533 and 537.1, providing PFAS water testing coverage across a range of global regulatory frameworks.
Restek's PFAS-10 Reduces Calibration Complexity for Compliant PFAS Water Testing
PFAS-10 consolidates ten linear compounds into one traceable reference material, eliminating the need to source, blend, and manage multiple individual standards for Japan Water Supply Act compliance. Every batch ships from stock with purity above 99% and lot-specific impurity data included, ready to integrate into existing LC-MS/MS workflows. For labs meeting Japan's mandatory quarterly testing obligations, PFAS-10 offers a direct, documented path to compliant PFAS water testing.
This article is based on a press release issued by Restek Corporation and was produced under Separation Science's AI Editorial Guidelines.
