Posts made in May 2021

EPA Adds Treatment Information for 11 PFAS

Last week (May 2021), in a Press Release, EPA announced they had added treatment information for the following 11 PFAS compounds to their Drinking Water Treatability Database:

  • Perfluoropentanesulfonic acid (PFPeS)
  • Perfluorohexanesulfonamide (PFHxSA)
  • Perfluorobutylsulfonamide (PFBSA)
  • Perfluoro-4-methoxybutanoic acid (PFMOBA)
  • Perfluoro-3-methoxypropanoic acid (PFMOPrA)
  • Perfluoro-3,5,7,9-butaoxadecanoic acid (PFO4DA)
  • Fluorotelomer sulfonate 4:2 (FtS 4:2)
  • Ammonium 4,8-dioxa-3H-perfluorononanoate (ADONA)
  • Perfluoro-4-(perfluoroethyl)cyclohexylsulfonate (PFECHS)
  • F-53B: a combination of 9-chlorohexadecafluoro-3-oxanone-1-sulfonic acid and 11-Chloroeicosafluoro-3-oxaundecane-1-sulfonic acid
  • Perfluoro-2-{[perfluoro-3-(perfluoroethoxy)-2-propanyl]oxy}ethanesulfonic acid, also known as Nafion BP2

EPA Press Release:

Link to information about EPA’s Drinking Water Treatability Database:

Link to EPA’s Drinking Water Treatability Database:

3M Sues Michigan Over PFAS MCLs

Earlier this month (May 2021), 3M sued the State of Michigan in an effort to overturn MCLs adopted in August 2020 for seven PFAS (see below).

Michigan National Public Radio quoted from a 3M statement as follows:

“Environmental regulations should be set using established processes and rigorous science that provide public transparency and accountability for regulators. In its rush to establish these regulations, the State of Michigan acted arbitrarily without measured consideration of the scientific evidence, nor serious consideration of the costs, particularly considering the speculative benefits of these regulations’ enforcement. This lawsuit aims to prevent these arbitrary, burdensome restrictions from being implemented unless regulators follow prescribed processes for rulemaking.”

From Michigan’s Press Release here is part of the State’s response:

“3M profited for years from its sale of PFAS products and concealed its evidence of adverse health impacts from state and federal regulators,” said Attorney General Nessel.  “It is no coincidence that this out-of-state company is resorting to attempts to rewrite our state’s standards put in place to protect Michiganders from PFAS in their drinking water.  3M knows it is responsible to address contamination in Michigan and it has been unwilling to do so. Now, it wants to change the rules so that it can continue to shirk its responsibility to Michigan residents and to the health of the water resources that define our state.”

Michigan Press Release in response to the lawsuit:,4629,7-136-3452-558805–,00.html

Michigan National Public Radio article:


In 2017 Michigan created MPART [Michigan PFAS Action Response Team] in response to PFAS contamination throughout the State.  MPART consists of members from the following State government departments: Environment, Great Lakes and Energy; Health and Human Services; Natural Resources; Agriculture and Rural Development; Transportation; Military and Veteran Affairs; and Licensing and Regulatory Affairs.

In March 2019, Governor Whitmer directed MPART to form a Science Advisory Workgroup that would “inform the rulemaking process for appropriate MCLs for PFAS.”   In June 2019 the three-member Science Advisory Workgroup recommended “health based” levels for the seven PFAS.  Three public hearings were held on the proposed MCLs in January 2020.  In August 2020 Michigan adopted final MCLs for the following seven PFAS:

PFNA (Perfluorononanoic acid) – 6 parts per trillion (ppt)

PFOA (Perfluorooctanoic acid)  – 8 ppt

PFHxA (Perfluorohexanoic acid) – 400,000 ppt

PFOS (Perfluorooctanesulfonic acid)  – 16 ppt

PFHxS (Perfluorohexane sulfonate)  – 51 ppt

PFBS (Perfluorobutane sulfonic acid)  – 420 ppt

HFPO-DA (Hexafluoropropylene oxide or Gen-X) – 370 ppt

OEHHA Recommended Cyanotoxin NLs

OEHHA Recommended NLs for Cyanotoxins

On February 4, 2021 the State Water Resources Control Board (SWRCB) Division of Drinking Water (DDW) submitted a written request to the California Office of Environmental Health Hazard Assessment (OEHHA) to develop recommended Notification Levels (NLs) for four cyanotoxins (copy of the February 4, 2021 DDW memo is here DDW Request to OEHAA for Cyanotoxin NLs_2021-02-04).

In response to that request, on May 3, 2021 OEHHA submitted the following recommended NLs to the SWRCB:

Anatoxin-a – Recommended NL 4 µg/L

Saxitoxins – Recommended Interim NL: 0.6 µg/L

Microcystins – Recommended Interim NL 0.03 µg/L

Cylindrospermopsin – Recommended Interim NL: 0.3 µg/L

Two memos from OEHHA to the SWRCB providing background and how the NLs were calculated are here (OEHHA NL_Anatoxin_2021-05-03 OEHHA_Interim NLs_Three Cyanotoxins_2021-05-03 ).

For three of the cyanotoxins, OEHHA recommended that the NLs be used on an interim basis “…while it completes its review of the sizeable database of recent toxicity studies on these cyanotoxins and derives final recommendations.”

Link to OEHHA announcement;