non-stick pans

PFAS – per- and polyfluoralkyl substances – are a group of organic compounds that have been extensively used to provide water-, oil-, and dirt-resistance to a wide range of products ranging from non-stick pans, clothing, and packaging to paint, car polish, and fire-suppressant foam. Exposure to specific PFAS compounds is associated with multiple adverse health effects, including altered immune and thyroid function, liver disease, kidney disease, poor reproductive and developmental outcomes, and cancer. PFAS compounds do not break down in the environment and therefore, over time, become concentrated in plants, animals, and people.

Government agencies such as the EPA in this country and the EU have set strict limits for allowable levels of PFAS in drinking water. Testing water for the trace amounts of PFAS that constitute the limits is time-consuming and expensive and requires complex equipment and experienced personnel.

Researchers at MIT have now introduced a technique for making a portable, inexpensive test that can easily and selectively detect PFAS in water samples. The test makes use of a special polymer containing fluorinated dye molecules that cause the polymer to fluoresce red. If PFAS are present in the sample, they enter the polymer and displace the dye molecules and switches off the red fluorescence.

The new technique is suitable for on-site detection in highly contaminated regions. Detecting smaller concentrations can be achieved with sufficient precision after pre-concentrating the samples using the process of solid-phase extraction.

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Tracking down Environmental Toxins

Photo, posted October 16, 2021, courtesy of Nenad Stojkovic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

One of the toughest classes of pollutants are per- and polyfluoralkyl substances, or PFAS, as they are known. PFAS are often called “forever chemicals” because they are extremely long-lasting and difficult to clean up. They are found in household products including non-stick pans, dental floss, water-repellent fabrics, and many others. They can be found extensively in U.S. waterways and soil.

PFAS move through the food chain, accumulating in humans at levels that scientists say can cause adverse health effects. While these have not been definitively proven, there is evidence that higher cholesterol levels, cancer, thyroid disruption, and low infant birth rates are all associated with PFAS ingestion.

PFAS are difficult to get rid of because their carbon-fluorine covalent bonds are some of the strongest in organic chemistry. Researchers at Princeton University have been studying a process known as Feammox in which ammonium breaks down in acidic, iron-rich soils in New Jersey wetlands and similar locations. They found that this reaction takes place when a bacterium called Acidimicrobium A6 is present.

Using gene-sequencing techniques, they found that the microbe has characteristics that could help break down carbon-fluorine bonds, and therefore break down PFAS. In tests using microbe-loaded soil samples, they found that the bacterium removed 60% of PFAS pollutants within 60 days.

The research has been published in the journal Environmental Science and Technology and the team is now testing the bacterium’s effectiveness over different time-spans in lab conditions before testing it in the field.

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New Jersey Soil Microbe Shown to Break Down ‘Forever Chemicals’

Photo, posted November 9, 2017, courtesy of the Department of Environmental Quality via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Tracking down PFAS toxins

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Breaking Down Forever Chemicals

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