Read the full article by Michigan Radio’s Stateside staff
“Over the past two years, Michiganders across the state have become aware of the chemicals known as PFAS. They first made news when elevated levels were found in more than 20 private water wells in Oscoda. Now, there are 35 known contamination sites around the state.
The term PFAS refers specifically to ‘per- and polyfluoroalkyl substances,’ (the term ‘PFCs,’ or perfluorinated chemicals is also sometimes used).
There are more than 4,000 different chemicals in this family, including two common ones called ‘PFOA’ and ‘PFOS.’ PFAS chemicals are known for their durability – they are incredibly resistant to most elements, which is why they’ve been used in materials ranging from waterproof shoes to firefighting foam to non-stick pots and pans since the 1950s.
The quality that gives PFAS chemicals such a wide range of industrial uses is also what makes them a public health hazard. These chemicals are nearly impossible to break down, meaning that they persist in the environment…
A recent national survey that examined large water systems found that systems with elevated levels of PFAS were linked to proximity to military fire training areas, wastewater treatment plants, and facilities that manufactured PFAS in the past. PFAS exposure typically results from contaminated drinking water as the chemicals cannot easily be absorbed through the skin.
Michigan Radio will be reporting on PFAS contamination across the state every day this week. Below, you’ll find Stateside conversations that answer listener-submitted questions about the chemicals’ impact in Michigan…
Tom Bruton is a scientist at the Green Science Policy Institute. He joined Stateside to discuss what makes PFAS chemicals so difficult to clean up…
‘Becuse PFAS are so persistent, a lot of the tools and tricks that engineers have for cleaning up water contamination don’t work for as well for PFAS,’ Bruton said.
Bruton has researched one method that does work for PFAS remediation: in-situ chemical oxidation.
‘It’s a little bit like adding bleach to your laundry. Bleach is an oxidant chemical. You add it to the laundry, it reacts with the stains in your clothes, the stains go away, the bleach doesn’t leave anything too nasty around. In-situ chemical oxidation is a similar process, where we introduce an oxidant underground, and hopefully detoxify the contaminants,’ he explained.
Unfortunately, because PFAS compounds are so stable, the treatment is not entirely effective. This method also requires a large amount of chemicals to be pumped into the ground.
The most common way to treat PFAS-contaminated water is the ‘pump and treat method.’ After water is pumped out of the ground, it is run through a PFAS-removing filter, then returned to the same spot. This, Bruton said, would be a costly and time-intensive solution. Addressing all the PFAS water contamination across Michigan would likely take decades and cost billions of dollars…
Rick Andrew is the Global Business Development Director of Water Systems at NSF International. He joined Stateside to discuss how NSF tests water filters that claim to treat for PFAS chemicals.
Manufacturers have created filters to treat PFOA and PFOS, two chemicals in the PFAS family. NSF, an independent global public health organization based in Ann Arbor, tests those filters to ensure they are, in fact, treating water for PFAS chemicals.
Andrew said the group’s main goal is to “make sure that the filter is treating those chemicals effectively when it is being used by people who are counting on it to provide clean, safe drinking water for their families.”
In order to be approved, the filters need to limit the water’s chemical concentration to 70 parts per trillion, which is the safety threshold set by the U.S. Environmental Protection Agency. The testing protocols ensure that approved filters are removing at least 95 percent of PFOS and PFOA in drinking water.
Andrew said the tests are difficult to control because the level of PFAS they are testing for is so low, but he said NSF has designed specialized equipment to accurately measure levels of PFAS…”