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I'm going to weight in because my partner is an environmental engineer who performs remediation of PFAS contaminated sites for the EPA and other Federal entitie

I'm going to weight in because my partner is an environmental engineer who performs remediation of PFAS contaminated sites for the EPA and other Federal entities. > Even though they 'stopped' using these chemicals in manufacturing 10-15 years ago, there's still an incredible level of contamination They haven't stopped using them, the chemicals are still used in stain and water resistant carpeting and textiles. They're used in cosmetics and sunscreens among other things. One of the biggest sources of contamination is fire retardant foams used in fire suppression. If you look at some of the sites in that report listed as having contaminated water, many are located near military bases, like Oceanside CA. These bases are the largest sources of ground water contamination of all sorts but specifically PFAS because they routinely practice fire suppression exercises. > 26,000 sites listed by EPA [1]. But that's sort of irrelevant, because these compounds don't break up over human time scales. PFAS is an emerging contaminant and isn't strictly regulated yet. Keeping track of these sites however is not irrelevant, it's extremely important that we know of and track these sites because they can and are being remediated. The current method of remediation involves setting up hundreds or thousands of ground water monitoring wells around a contamination site to track the plumes and then using pumps to remove the ground water and filter it through activated carbon filters. The filters are treated as hazardous waste and incinerated. > It's hard not to be alarmist about this, PFAS contamination is genuinely terrifying. I wouldn't say you're being alarmist at all, if anything the current response to PFAS is insufficient and we should be treating it as a public health crisis at least on par with Lead.

hammock 6y ago
>If you look at some of the sites in that report listed as having contaminated water, many are located near military bases, like Oceanside CA. These bases are the largest sources of ground water contamination of all sorts but specifically PFAS because they routinely practice fire suppression exercises. I read a report recently that suggested the DoD was scrambling to incinerate its firefighting foam supplies, to avoid a PR disaster. However, the safety of incineration as disposal method has been called into serious question, namely that it doesn't sufficiently break it down and instead distributes it more widely through the environment. Any insight from you or your partner?
- cptskippy 6y ago
  According to my partner, the purpose of incineration is to break down the sulfur bonds rendering the resultant chemicals inert. However one of the attractive characteristics of PFAs is it's stability, so breaking these bonds requires a tremendous amount of energy. No particular insight into the DoD's disposal but it's entirely possible, and wouldn't be surprising, to find that the DoD is carrying out the destruction improperly.
  - nate_meurer 6y ago
    > so breaking these bonds requires a tremendous amount of energy. Nope. C-F bonds are chemically very stable, but they exhibit high thermal reactivity and degrade far below proper incineration temperatures. Proper incineration, where the flu gasses are maintained at over 800 deg C, will easily drive all flourinated organics to their mineral endpoint, which is HF. And none of this has anything to do with the sulfur. For one thing, most end-use PFA products don't contain any sulfur. PTFE, for example, has no sulfur in it, yet many of its thermal degradation products are quite toxic. Sulfur is only present in chemicals used as surfactants, such as the water repellent coatings and fire retardants. But there is no evidence that merely cleaving the sulfonate group would make the compounds harmless.
    - petertodd 6y ago
      Good example re: thermal reactivity is how teflon coated pans can kill birds if you let them overheat, eg by letting a pan boil dry: http://www.animalplanet.com/pets/other-pets/teflon-bird-guide/ http://www.animalplanet.com/pets/other-pets/teflon-bird-guid... Causes harm to humans too. But birds happen to be particularly susceptible. Looks like the research agrees with you re: incineration: https://www.sciencedirect.com/science/article/pii/S0045653519306435 https://www.sciencedirect.com/science/article/pii/S004565351... "Results indicate that, within procedural quantitation limits, no statistically significant evidence was found that the PFAS studied were created during the incineration of PTFE. Therefore, municipal incineration of PTFE using best available technologies (BAT) is not a significant source of the studied PFAS and should be considered an acceptable form of waste treatment."
aerojoe23 6y ago
Do we know if the incinerated breaks down the PFAS into something that will biodegrade?
- cptskippy 6y ago
  According to my partner, the purpose of incineration is to break down sulfur bonds and render the chemicals inert.
  - nate_meurer 6y ago
    This doesn't really make sense. Removing the sulfonate group would render the chemical non-polar, but the effect on biological activity is still unknown. Aside from that, and to answer the question, proper incineration will completely destroy all fluorinated organics. The only fluorine left is HF, which will be removed by the scrubbers.
    - cptskippy 6y ago
      > This doesn't really make sense. That's entirely possible. We're playing a game of telephone between a software developer and a civil/environmental engineer.
hanniabu 6y ago
> PFAS is an emerging contaminant and isn't strictly regulated yet It's not emerging, it's been around a while. Big business just keeps regulation at bay.
- cptskippy 6y ago
  > It's not emerging, it's been around a while. The term "Emerging Contaminant" doesn't mean we're only just starting to use it or that it's only just starting to become a problem. It means we're only just starting to realize the gravity of the situation we've put ourselves into by using it heavily for decades. In layman's terms "Oh fuck".
  - hanniabu 6y ago
    The gravity of the situation was known long ago. Dark Waters is a great film about it.
deleted 6y ago
[deleted]
xedeon 6y ago
> If you look at some of the sites in that report listed as having contaminated water, many are located near military bases, like Oceanside CA Precisely, the military has used PFAS in firefighting foams on aircraft, ship fires and training. Here is a map of the military sites that showed elevated levels of PFAS: https://www.ewg.org/interactive-maps/2020-military-pfas-sites/map/ https://www.ewg.org/interactive-maps/2020-military-pfas-site...
yabones 6y ago
Thanks for sharing and putting it in perspective. Would you recommend any articles/books/papers to learn more about the reality of PFAS contamination, especially when it enters the broader water supply (ie. outside bases)?

hammock 6y ago

>If you look at some of the sites in that report listed as having contaminated water, many are located near military bases, like Oceanside CA. These bases are the largest sources of ground water contamination of all sorts but specifically PFAS because they routinely practice fire suppression exercises. I read a report recently that suggested the DoD was scrambling to incinerate its firefighting foam supplies, to avoid a PR disaster. However, the safety of incineration as disposal method has been called into serious question, namely that it doesn't sufficiently break it down and instead distributes it more widely through the environment. Any insight from you or your partner?

cptskippy 6y ago
According to my partner, the purpose of incineration is to break down the sulfur bonds rendering the resultant chemicals inert. However one of the attractive characteristics of PFAs is it's stability, so breaking these bonds requires a tremendous amount of energy. No particular insight into the DoD's disposal but it's entirely possible, and wouldn't be surprising, to find that the DoD is carrying out the destruction improperly.
- nate_meurer 6y ago
  > so breaking these bonds requires a tremendous amount of energy. Nope. C-F bonds are chemically very stable, but they exhibit high thermal reactivity and degrade far below proper incineration temperatures. Proper incineration, where the flu gasses are maintained at over 800 deg C, will easily drive all flourinated organics to their mineral endpoint, which is HF. And none of this has anything to do with the sulfur. For one thing, most end-use PFA products don't contain any sulfur. PTFE, for example, has no sulfur in it, yet many of its thermal degradation products are quite toxic. Sulfur is only present in chemicals used as surfactants, such as the water repellent coatings and fire retardants. But there is no evidence that merely cleaving the sulfonate group would make the compounds harmless.
  - petertodd 6y ago
    Good example re: thermal reactivity is how teflon coated pans can kill birds if you let them overheat, eg by letting a pan boil dry: http://www.animalplanet.com/pets/other-pets/teflon-bird-guide/ http://www.animalplanet.com/pets/other-pets/teflon-bird-guid... Causes harm to humans too. But birds happen to be particularly susceptible. Looks like the research agrees with you re: incineration: https://www.sciencedirect.com/science/article/pii/S0045653519306435 https://www.sciencedirect.com/science/article/pii/S004565351... "Results indicate that, within procedural quantitation limits, no statistically significant evidence was found that the PFAS studied were created during the incineration of PTFE. Therefore, municipal incineration of PTFE using best available technologies (BAT) is not a significant source of the studied PFAS and should be considered an acceptable form of waste treatment."

aerojoe23 6y ago

Do we know if the incinerated breaks down the PFAS into something that will biodegrade?

cptskippy 6y ago
According to my partner, the purpose of incineration is to break down sulfur bonds and render the chemicals inert.
- nate_meurer 6y ago
  This doesn't really make sense. Removing the sulfonate group would render the chemical non-polar, but the effect on biological activity is still unknown. Aside from that, and to answer the question, proper incineration will completely destroy all fluorinated organics. The only fluorine left is HF, which will be removed by the scrubbers.
  - cptskippy 6y ago
    > This doesn't really make sense. That's entirely possible. We're playing a game of telephone between a software developer and a civil/environmental engineer.

hanniabu 6y ago

> PFAS is an emerging contaminant and isn't strictly regulated yet It's not emerging, it's been around a while. Big business just keeps regulation at bay.

cptskippy 6y ago
> It's not emerging, it's been around a while. The term "Emerging Contaminant" doesn't mean we're only just starting to use it or that it's only just starting to become a problem. It means we're only just starting to realize the gravity of the situation we've put ourselves into by using it heavily for decades. In layman's terms "Oh fuck".
- hanniabu 6y ago
  The gravity of the situation was known long ago. Dark Waters is a great film about it.

deleted 6y ago

[deleted]

xedeon 6y ago

> If you look at some of the sites in that report listed as having contaminated water, many are located near military bases, like Oceanside CA Precisely, the military has used PFAS in firefighting foams on aircraft, ship fires and training. Here is a map of the military sites that showed elevated levels of PFAS: https://www.ewg.org/interactive-maps/2020-military-pfas-sites/map/ https://www.ewg.org/interactive-maps/2020-military-pfas-site...

yabones 6y ago

Thanks for sharing and putting it in perspective. Would you recommend any articles/books/papers to learn more about the reality of PFAS contamination, especially when it enters the broader water supply (ie. outside bases)?