The future of forever chemistry

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PFAS chemicals are characterized by a carbon-fluorine backbone (the “F-C” in “forever chemicals”) – the carbon-fluorine bond is one of the strongest bonds in organic chemistry.

The incredible complexity of our global ecosystem … at so many levels …

Well, then there’s “better living through chemistry” … the plastic ocean, plastic in our food chain, and PFAS in our tap water (and blood).

Here’s one of many articles in the news cycle this week prompted by a recent study from the United States Geological Survey (USGS) – which “analyzed water collected from over 700 taps and kitchen faucets in homes, offices and schools across the country.”

• The Washington Post > “Toxic ‘forever chemicals’ taint nearly half of U.S. tap water, study estimates” by Kate Selig (July 6, 2023)

The federal [USGS] study, one of the most extensive of its kind looking directly at water coming out of a tap, adds to a body of research showing that PFAS — per- and polyfluoroalkyl substances — chemicals are not only long-lasting but widespread in drinking supplies.

PFAS refers to more than 12,000 chemicals that persist in the environment and can build up in the body. They are widely used in industry and consumer products, ranging from clothing and cosmetics to fast-food wrappers and microwave popcorn bags.

“Millions of people have been drinking a toxic forever chemical linked to cancer all their lives and are only discovering it today,” Scott Faber, the senior vice president for government affairs at the Environmental Working Group, said Thursday on the research.

They [the researchers] … tested the water for the presence of 32 types of PFAS. (… the few that can be analyzed at this time … .)

The researchers more frequently detected PFAS in urban areas or areas next to potential sources of the chemicals such as airports, industry and wastewater treatment plants, Smalling said. She estimated that about 75 percent of urban tap water has at least one type of PFAS present, compared with about 25 percent of rural tap water.

Elsie Sunderland, a professor of environmental chemistry at Harvard, added that the numbers are “alarming” but cautioned that the sample size could be too small to draw sweeping assumptions from the USGS study alone.

What is being done

  • In March, the Environmental Protection Agency proposed the first drinking water standard for some PFAS.
  • The manufacturing giant 3M also announced at the end of June … to pay $10.3 billion over 13 years to cover testing for and cleaning up PFAS in water supplies across the country.
  • States are also stepping up action on PFAS, including through legislation banning or restricting the use of PFAS in everyday products and implementing drinking water standards.

What needs to be done

  • Regulate the companies that are producing these chemicals.
  • Filter potable water (some filters can remove PFAS).

4 comments on “The future of forever chemistry”

  1. Modeling global climate change … and more regional ecosystem tipping points. Getting better levels of complexity, a better handle on key drivers (destabilizing factors).

    Terms: tipping point

    • Space.com > “Catastrophic climate ‘doom loops’ could start in just 15 years, new study warns” by Ben Turner (July 8-2023)

    According to the research, more than a fifth of the world’s potentially catastrophic tipping points — such as the melting of the Arctic permafrost, the collapse of the Greenland ice sheet and the sudden transformation of the Amazon rainforest into savanna — could occur as soon as 2038.

    Unlike the well-established link between the burning of fossil fuels and climate change, the study of tipping points is a young and contentious science.

    Tipping point

  2. Water filter

    In response to the USGS survey of our nation’s tap water …

    Are consumer water filter pitchers effective at fully filtering out PFAS?

    ARTICLE

    • cbsnews.com > Health > “Environmental group tests to find the best water filters for removing PFAS” (includes video) by Stephanie Stahl (July 11, 2023) – To work properly, filters need to be changed, which can be costly.

    PHILADELPHIA (CBS) — Water filters have become more popular following studies that show nearly half of the country’s tap water could be contaminated with potentially toxic compounds. But which are the best water filters?

    There are different ways to filter your water at home, according to a recent study focused on specialized pitchers that are designed to block PFAS, also known as forever chemicals.

    The Environmental Working Group tested 10 water pitchers and found some of the most well-known are “not” effective at fully filtering out PFAS.

    SOURCE

    • ewg > “Getting ‘forever chemicals’ out of drinking water: EWG’s guide to PFAS water filters” by Sydney Evans, EWG (July 11, 2023) – Overview | Best overall | Recommended | Others we tested (including the popular Brita Filter Pitcher, 6-Cup) | Methodology

    For this guide, EWG bought 10 different types of filters, including some that claimed to reduce PFAS in drinking water. We tested for 25 individual PFAS using SimpleLab’s GenX and PFAS Water Test.

    EWG’s guide has limitations. Our test results provide only a snapshot of how these filters work, since we only tested one of each filter and one water sample from each filter.

    • ewg > “EWG tests find four water filters that effectively remove ‘forever chemicals’ from home taps” (July 2023) – EWG researchers tested the performance of 10 popular home water filters.

    WASHINGTON – New laboratory tests commissioned by the Environmental Working Group found four water filters that reduce the detected “forever chemicals” known as PFAS in sampled drinking water by nearly 100 percent.

    “It’s crucial that after choosing a filtration system, you keep changing the water filter,” said Tasha Stoiber, Ph.D., a senior scientist at EWG. “If you don’t change it, and it becomes saturated, the levels of PFAS in the filtered water can go above the levels coming from the tap.”

    Water utilities nationwide are testing drinking water for 29 PFAS compounds as part of the EPA’s Fifth Unregulated Contaminant Monitoring Rule. Those tests are taking place between 2023 and 2025, with some data expected to be released this summer.

  3. Electrochemical filtering of PFAS using metallocenes

    Caption: Graphical representation of a metal-containing polymer with ferrocene units used for reversible uptake of perfluorinated compounds. Credit: Markus Gallei, Professor of Polymer Chemistry at Saarland University.

    So, if I use water filters to remove PFAS (among other things), a major concern is disposal of used filters. Manufacturers (and local waste collection services) are more or less transparent on this subject. Some have established 3rd-party recycling partnerships. But, in general, my impression (from experience and online research) is that most used water filters end up in landfills (much like most plastic).

    The filters themselves may be environmentally hazardous: (a) the plastic containers; and (b) the 10’s of thousands of activated carbon & zinc-copper-resin beads). Then there’s the filtered out contaminants as well.

    • Phys.org > “Chemists develop sustainable method to remove ‘forever chemicals’ from water” by Saarland University (July 6, 2023) – The research is published in the journal ACS Applied Materials & Interfaces.

    Key points

    1. PFAS remediation is both complex and challenging, and the processes used can themselves have a detrimental impact on the environment and the climate.

    2. Detection of PFAS is challenging because only small quantities are required for a large effect.

    3. Conventionally, recovering the PFAS from water filter systems – so that they can be permanently destroyed – either requires the use of harsh chemical conditions or incineration.

    4. A new electrochemical method can remove PFAS chemicals from water and then efficiently release them again for destruction (without needing to incinerate the filter).

    5. Unlike systems using activated carbon filters (which have to destroyed once saturated with PFAS molecules), the new electrochemical filtering method – using metallocenes (metal-containing polymers) – is regenerative, allowing ready release of captured PFAS molecules and continued use of the filter.

  4. Microwave safe

    The Anthropocene epoch, the Plastic era. It’s cheap, it’s convenient, almost indispensable in so many ways … “can’t live with ’em, can’t live without ’em” … if companies “knowingly produce” something that releases micro/nano plastics …

    Yeah, I haven’t used plastic containers in my microwave for decades. (My favorite containers are made of borosilicate glass.) I probably noticed articles about leaching toxic chemicals into the food (aside from some “microwave safe” plastics melting or cracking). The article below is a reminder of the pervasive presence of plastics in our food chain, in our bodies, and the cumulative impact on future generations.

    “Microwave safe” is not a certification – such branding of polypropylene jars, reusable food pouches, etc., does not fool chemistry. Or our kidneys.

    Microwaving delivers a triple whammy: heat, UV irradiation, and hydrolysis, a chemical reaction through which bonds are broken by water molecules.

    • Wired > “For the Love of God, Stop Microwaving Plastic” by Celia Ford (July 31, 2023) – A study of baby-food containers shows that microwaving plastic releases millions upon millions of polymer bits.

    As a new dad and a PhD student studying environmental nanotechnology … Hussain [Kazi Albab Hussain] wanted to know how much was being released from the kinds of containers he’d been buying. So he went to the grocery store, picked up some baby food, and brought the empty containers back to his lab at the University of Nebraska—Lincoln. In a study published in June in Environmental Science & Technology, Hussain and his colleagues reported that, when microwaved, these containers released millions of bits of plastic, called microplastics, and even tinier nanoplastics.

    … nanoplastics are small enough to slip across cell membranes … “the chemicals used in plastics hack hormones,” says Leonardo Trasand, a professor at the NYU Grossman School of Medicine and the director of the Center for the Investigation of Environmental Hazards.

    To get a plastic product approved for food or beverage packaging, a manufacturer needs to submit a limited amount of self-reported data to the FDA. But the agency doesn’t have the resources to test the safety of all plastic products before they go on the market or to spot-check them once they’re available in stores.

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