Health Risk Limits Rules
- Health Risk Limits Rules Home
- Rule Amendments
- Overview and Links
- Comments Received
- Contaminants
- Dual Notice
- Proposed Rules
- Request for Comments
- SONAR
- Current HRL Rules
- Rulemaking & Guidance History
- SONARs
Related Topics
Environmental Health Division
Health Risk Limits Rules for Groundwater
Rules Amendments - Contaminants
August 2025
MDH proposes amendments to the Health Risk Limits (HRLs) Rules approximately every two years. This allows new and updated human health-based water guidance values to be considered for adoption into rule.
In June 2023, the Minnesota Legislature passed a session law that requires Minnesota Department of Health to "...amend the health risk limit for perfluorooctane sulfonate (PFOS) in Minnesota Rules, part 4717.7860, subpart 15, so that the health risk limit does not exceed 0.015 parts per billion..." (Laws of Minnesota, Chapter 60, Article 3, Section 34) This rulemaking began in August 2023 and ended in August 2025 with the adoption of updated values for the contaminants listed below. See Health Risk Limits Health Risk Limits Rules Amendments: Overview and Links for more information.
Contaminants included in additional Session Law rulemaking for Health Risk Limits (estimated timeframe: 2023-2025)
| Chemical Abstract Service (CAS) Number | Chemical Name | Previously adopted values in HRL Rule? (year adopted) |
| 120-12-7 | Note: This outdated value will be repealed only. New RAA guidance is already available. | Yes (1993) |
| 1897-45-6 | Chlorothalonil | Yes (1994) |
| 106-93-4 | 1,2-Dibromoethane (ethylene dibromide, EDB) | Yes (1993) |
| 75-71-8 | Note: This outdated value will be repealed only. New RAA guidance is already available. | Yes (2011) |
| 45298-90-6; 1763-23-1; 29081-56-9; 70225-14-8; 2795-39-3; 9457-72-5 | Yes (2009) | |
| 45285-51-6; 335-67-1; 3825-26-1; 2395-00-8; 335-95-5; 335-93-3 | Yes (2018) |