What is the Massachusetts drinking water standard?

On October 2, 2020, MassDEP published its public drinking water standard or Massachusetts Maximum
Contaminant Limit (MMCL) of 20 nanograms per liter (ng/L) or parts per trillion (ppt) – for the sum of the
concentrations of six PFAS. The six PFAS are: perfluorooctane sulfonic acid (PFOS); perfluorooctanoic acid
(PFOA); perfluorohexane sulfonic acid (PFHxS); perfluorononanoic acid (PFNA); perfluoroheptanoic acid
(PFHpA); and perfluorodecanoic acid (PFDA). MassDEP abbreviates this set of six PFAS as “PFAS6.” This
drinking water standard is set to be protective against adverse health effects for all people consuming the

For information on the PFAS6 drinking water standard see: 310 CMR 22.00: The Massachusetts
Drinking Water Regulations
. For more information about the technical details behind the MMCL, see MassDEP’s technical support document at: Per- and Polyfluoroalkyl Substances (PFAS): An Updated Subgroup Approach to
Groundwater and Drinking Water Values

Show All Answers

1. What are PFAS and how are people exposed to them?
2. What is the Massachusetts drinking water standard?
3. What health effects are associated with exposure to PFAS6?
4. How can I find out about contaminants in my drinking water?
5. What options should be considered when PFAS6 in drinking water is above MassDEP’s drinking water standard?
6. Where can I get more information on PFAS?
7. Where can I find more information about Treatment Devices for PFAS?