New Hampshire: Updated PFAS MCLs

June 27, 2019

On June 28, New Hampshire announced updated PFAS MCLs. The main difference in the updated MCLs is that NH is now using the Minnesota model that accounts for higher exposures of breastfed infants.  Other cahnges include that the Reference Dose for PFOS is now based on immune system toxicity.  These new updated MCLs will not go out for public comment, but will go through an administrative process in order to be finalized.

Specific PFAS Updated (ppt) Current (ppt)
PFOA  12 38
PFOS  15 70
PFHxS 18 85
PFNA  11 23


Additional infomration: 

  • Press release (link
  • Technical support document (link)
  • NH DES response to public comments on the earlier MCLs proposed in January (link)