Do they want to be underwater or something?
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full text without a paywall
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PFAS and other perflorinated compounds are certainly not “isolated” to anything, unless your constraint is “Planet Earth.”
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TIL some trivia…
The first piece of which is that there is an international news letter for the filtration industry, “International Filtration News”. 
(That publication is now on my reading list right up there with the Magazine of the National Parking Association, which is to say, “not”.) 
If I’m ever in Beaver Falls PA I must find out if they commemorate Thomas Midgley Jr., born there and largely responsible for the environmental disasters which were leaded gasoline and CFCs (Freon), two of Time Magazine’s “50 Worst Inventions” (IMHO a spectacular understatement). My second piece of trivia, which I learned from International Filtration News, is that Teflon is just polymerized (edit:) polymerized from the class of chemicals that includes Freon. So we can at least partially credit Midgley with this environmental disaster as well. 
(Edit: corrected by a chemist, below.)
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That’s not true. Teflon is polymerized tetrafluorethene (generically referred to as PTFE outside of NA). You can’t polymerize Freon (at least not classic Freon-12)… it’s methane-based, so no double bond with which to polymerize (and I’m pretty sure there’s chlorine involved, which is what gave Freon it’s ozone busting capabilities).
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OK, now I really need to know the full answer here, having never even thought about there being any connection at all between Teflon (a polymer) and Freon (a type of liquid gas, I thought) before.
I don’t even know enough to figure out how to look it up.
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This is going on stuff I learned a long time ago when the ozone hole was all the hype. Freon is one of a class of material called a chlorofluorocarbon (CFC), so named because they are composed entirely of chlorine, fluorine and carbon atoms. Freon’s major properties are that it’s pretty inert chemically, has a high latent heat of vaporization and readily changes state at around room temperature given changes in pressure, either absorbing or releasing that latent heat when it changes phase, which allows you to move heat from one place to another. Unfortunately, upon exposure to unfiltered sunlight, Freon breaks down into its constituent parts, including chlorine, which breaks ozone down into oxygen when it’s in the stratosphere.
Tetrafluoroethene is related to CFCs, (being made of fluorine and carbon, but no chlorine, so it’s not a CFC, but the same company discovered it since they were messing with organic compounds with halogens) but has very different properties from Freon (it’s not inert at all and can be polymerized for two).
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Huh… OK, I’m not a chemist, the article lumps Freon in with “these compounds” which was a jump I should have made more carefully:
Midgley was subsequently demoted and went on to work on the development of less toxic and less reactive refrigerants, which was a major issue in the 1920s. The result was Freon 12 (dichlorodifluoro methane). At the time it seemed like a major breakthrough. It was of low toxicity, reactivity and was an excellent heat transfer fluid. It was accidentally discovered that polymerization of these compounds created Teflon. It replaced all other refrigerants for a while.
Still… Midgely eh?
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That was very helpful…thank you!
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The worst drought in…1,200 years!
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There needs to be an national plan to bring water to all those people now. And address the climate issues.
The current plan seems to be - I guess they’ll move when they’re in terminal dehydration. It won’t be pretty.
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Bow before your corvid overlords!!
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