PFAS
What is PFAS?
Per- and polyfluoroalkyl substances (PFAS) are a family of chemicals that are made and distributed by many companies around the world and are used in a variety of products and manufacturing processes. Eventually, these “forever chemicals” reached the groundwater aquifers serving east metro communities and trace amounts have been detected in Oak Park Heights drinking water source.
PFAS presence in drinking water has generated a lot of attention, as water is one of the most managed and monitored areas when it comes to PFAS. But it’s important to note that PFAS chemicals are present in many other areas of our environment and in thousands of products. According to the Minnesota Department of Health (MDH) website, PFAS can be measured in the blood of most people around the world, including Minnesotans. Consumer products that are grease, oil, stain and/or water resistant are a much greater source of PFAS exposure than drinking water.
For most Minnesotans, the majority of PFOS exposure comes from non-drinking water sources. These can include:
- food packaging (fast food containers/wrappers, pizza boxes, microwave popcorn bags and candy wrappers),
- stain resistant carpets, upholstery, and other fabrics,
- water resistant clothing,
- cleaning products,
- non-stick cookware,
- personal care products and cosmetics (e.g., shampoo, dental floss, nail polish and eye makeup); and
- paints, varnishes and sealants,
- Fire-fighting foam,
- Industrial Processes.
New MN Dept of Health Standards for PFOS and PFOA
The Environmental Protection Agency (EPA) and Minnesota Department of Health (MDH) continues to study the health effects of PFAS and periodically updates its guidance level for two specific types of PFAS. The new MDH drinking water guidance values, based on daily consumption over a lifetime, for PFOS and PFOA are 2.3 and 0.0079 parts per trillion, respectively. These are extremely low levels and, in some cases, current technology does not yet exist to detect these levels. One part per trillion (ppt) denotes one part per 1,000,000,000,000 (1012) parts. This is equivalent to about thirty (30) seconds out of every million years or one drop in an Olympic size swimming pool that is 4,000 feet deep.
How much PFAS is in OPH Drinking Water?
On April 10, 2024, the EPA finalized the current Maximum Containment Levels (MCL’s) for four (4) PFAS chemicals and set a hazard index formula for a combination of chemicals known as Gen X chemicals. The level of PFAS chemicals detected in OPH’s water is lower than the EPA’s enforceable MCL’s. However, Oak Park Heights is anticipating the MDH will issue a drinking water advisory regarding trace detections of PFOA at levels above .0079 ppt in both municipal wells.
Actions we are taking.
Since PFAS levels in OPH water is lower than the EPA’s enforceable MCL’s, no action is required at this time. However, if detected PFAS levels in our source water ever exceed the EPA’s MCL’s, the City would be required to filter water through granular activated carbon or ion exchange resin. The roughly estimated cost for the City could be between $13 - $20 Million dollars for treatment facilities. Given such costs, assistance from the Federal Government and State will be needed. The City currently is seeking $500,000 in State funding to allow us to complete preliminary feasibility studies and preliminary design to determine the best approach to remove PFAS from our drinking water supply.
The City has also opted into a nationwide class action lawsuit against Dupont and 3M, two among many companies that create and or distribute PFAS chemicals. Both suits were settled with neither defendant admitting liability. DuPont agreed to pay $1,185,000,000 and 3M agreed to pay $12,500,000,000 to be distributed among the nations qualified drinking water systems that opted in to the class action. Due to the presence of PFAS in our water supply, OPH is qualified to receive settlement dollars, although the amount is not yet known.
What can you do?
The most effective methods of removing PFAS chemicals from water is filtering it. Filters containing activated carbon or reverse osmosis membranes have been shown to be effective at removing PFAS from water supplies. But remember, all water treatment units require regular maintenance to work properly. Water treatment units that are not properly maintained will lose their effectiveness over time. Visit the MN Department of Health PFAS and Home Treatment of Water website for more detail.
If PFAS chemical concentrations are so low, why does it matter?
Research and monitoring is ongoing and it is anticipated that the MDH and the EPA will make adjustments to health advice as each considers necessary. For more detail including a history of PFAS, testing results and information related to PFAS, visit the MN Department of Health PFAS Page and visit the City of Oak Park Heights website www.cityofoakparkheights.com for updates as we work through this new regulation.
Oak Park Heights Test Results Compared to the EPA (Federal) PFAS MCL’s
|
Compound |
OPH Well1 |
Final MCL (enforceable levels) |
Compound |
OPH Well 2 |
Final MCL (enforceable levels) |
|
PFOA |
2.68 ppt |
4.0 parts per trillion (ppt) (also expressed as ng/L) |
PFOA |
2.6 ppt |
4.0 parts per trillion (ppt) (also expressed as ng/L) |
|
PFOS |
0 ppt |
4.0 ppt |
PFOS |
0.26 ppt |
4.0 ppt |
|
PFHxS |
1.3 ppt |
10 ppt |
PFHxS |
6.5 ppt |
10 ppt |
|
PFNA |
0 ppt |
10 ppt |
PFNA |
0 ppt |
10 ppt |
|
HFPO-DA (commonly known as GenX Chemicals) |
0 ppt |
10 ppt |
HFPO-DA (commonly known as GenX Chemicals) |
0 ppt |
10 ppt |
|
Mixtures containing two or more of PFHxS, PFNA, HFPO-DA, and PFBS |
0.13 |
1 (unitless) |
Mixtures containing two or more of PFHxS, PFNA, HFPO-DA, and PFBS |
0.91 |
1 (unitless) |
|
Hazard Index |
Hazard Index |
Hazard Index |
Hazard Index |
MDH Health-based Values for PFAS
|
PFAS Detected in Minnesota PFAS Specific Information Sheet Available |
Drinking Water Guidance Value (ppb) |
|
perfluorobutane sulfonate (PFBS) |
0.1 |
|
perfluorobutanoic acid (PFBA) |
7 |
|
perfluorohexane sulfonate (PFHxS) Toxicological Summary for: perfluorohexane sulfonate (PFHxS) (PDF) |
0.047 |
|
perfluorohexanoic acid (PFHxA) |
0.2 |
|
perfluorooctanoic acid (PFOA) |
0.0000079 |
|
perfluorooctane sulfonate (PFOS) |
0.0023 |
Oak Park Heights Test Results Compared to Minnesota Department of Health: Health Based Values (Unenforceable)
|
Chemical |
MDH HBV in ppt |
Well 1 Results |
Well 2 Results |
|
PFBS |
100 ppt |
1.47 ppt |
5.08 ppt |
|
PFBA |
7,000 ppt |
115 ppt |
100 ppt |
|
PFHxS |
47 ppt |
1.56 ppt |
7.68 ppt |
|
PFHxA |
200 ppt |
1.65 ppt |
4.13 ppt |
|
PFOA |
.0079 ppt |
2.68 ppt |
2.63 ppt |
|
PFOS |
2.3 ppt |
0 ppt |
0.39 ppt |