MSHHSD Issues PFAS Public Health Drinking Water Screening Levels for PFAS
The Michigan Department of Health and Human Services, Division of Environmental Health (MSHHSD) has released its report which sets forth “screening levels” for PFOA, PFOS, PFNA, PFHxS, PFBS. Human exposure to per- and polyfluoroalkyl substances (PFAS) is a public health concern that the MSHHSD has been working on with the Michigan PFAS Action Response Team’s (MPART) and other agencies.
Drawing heavily on toxicological profiles and analysis used by the State of Minnesota and the yet to be finalized federal Agency for Toxic Substances and Disease Registry (ATSDR), MSHHSD has set the following limits for public drinking water, stating the limits protect the most vulnerable of the population:
- PFOA - 9 ng/L (parts per trillion [ppt])
- PFOS 8 ng/L (ppt)
- PFNA 9 ng/L (ppt)
- PFHxS 84 ng/L (ppt)
- PFBS 1000 ng/L (ppt)
While these “screening levels” have no immediate regulatory effect, they will be used by MSHHSD in making recommendations related to PFAS in drinking water and more importantly, will serve as the starting point for MPART’s consideration of health based values for the state’s Maximum Contaminant Levels for PFAS in drinking water. Michigan Department of Environmental Quality (soon to be Michigan Department of Environment, Great Lakes and Energy (EGLE)) Director Liesl Clark and MPART have set forth an aggressive schedule for final promulgation of PFAS Maximum Contaminant Levels (MCLs) by April of 2020. The schedule provides that the newly appointed 3 person Science Advisory Workgroup is to recommend health based values for the MCLs by July 1, 2019, leaving the workgroup less than three months to review other toxicological data and information to make their recommendations.
While MSHHSD has issued drinking water screening levels for other chemicals in the past that are less than corresponding MCLs, the PFAS screening levels developed by MSHHSD are significantly less than EPA’s health advisory level of 70 ppt and may be a signal of where MPART and EGLE are headed. Given the aggressive time frame the state has set for promulgating PFAS MCLs and MSHHSD’s issuance of its screening levels in advance of MPARTs promulgation process, it is questionable as to how much public input will be considered despite MPART’s insistence that the MCLs will be developed in an open and transparent process. More to come……