Risk Assessment
Related Topics
Environmental Health Division
Chemicals Under Review
The Health Risk Assessment unit conducts reviews for contaminants through the Health Risk Limits program and Contaminants of Emerging Concern initiative. Contaminants are selected for review in partnership with state agencies or may be submitted for review from the public for the Contaminants of Emerging Concern initiative.
Completed contaminant reviews and their year of completion are available on the Human Health-based Water Guidance Values Table.
2026 Contaminants under review table
| Chemical Name | CAS Number* | Program or Initiative | Date Posted |
|---|---|---|---|
| Arsenic | 7440-38-2 | Health Risk Limits | 5/29/2025 |
| o-Toluidine | 95-53-4 | Contaminants of Emerging Concern | 4/3/2025 |
| Pyroxasulfone and Pyroxasulfone M1 | 447399-55-5 1379794-40-7 | Health Risk Limits | 3/25/2025 |
| Trifluoroacetate (TFA) | 14477-72-6 | Contaminants of Emerging Concern | 4/9/2025 |
Guidance completed in the past two years
| Contaminant Name | CAS Number* | Program or Initiative | Date completed |
|---|---|---|---|
| Sulfentrazone | 122836-35-5 | Health Risk Limits | April 2025 |
| Sulfentrazone 3-Carboxylic Acid | 134391-01-08 | Health Risk Limits | April 2025 |
| Tributyl Phosphate | 126-73-8 | Contaminants of Emerging Concern | April 2025 |
| Methyl Ethyl Ketone | 78-93-3 | Health Risk Limits | March 2025 |
| Perfluorooctane Sulfonate (PFOS)) | 45298-90-6; 1763-23-1; 29081-56-9; 70225-14-8; 2795-39-3; 29457-72-5 | Contaminants of Emerging Concern | 2024 (Adopted as Rule in August 2025) |
| Perfluorooctanoate (PFOA) | 45285-51-6; 335-67-1; 3825-26-1; 2395-00-8; 335-95-5; 335-93-3 | Contaminants of Emerging Concern | 2024 (Adopted as Rule in August 2025) |
| Diketonitrile (DKN) (Degradate of Isoxaflutole) | 143701-75-1 | Health Risk Limits | May 2024 |
| Isoxaflutole | 141112-29-0 | Health Risk Limits | May 2024 |
*CAS Number = Chemical Abstracts Service Registry Number
Last Updated: 02/09/2026