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A comment on The EPA is proposing that 'forever chemicals' be considered hazardous substances. Parent comment

Re:The EPA is proposing that 'forever chemicals' be consider... by timr on Friday February 02, 2024 @06:32PM (#39235967)
PTFE is not a PFAS unless you define PFAS so broadly as to be meaningless.

They're common only in that they both contain polyfluorinated carbon chains.

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Re:The EPA is proposing that 'forever chemicals' be consider... by StableAlkyne on Friday February 02, 2024 @08:24PM (#39236744)
Polytetrafluoroethylene is a polymer where the individual monomers are fluorinated alkanes.

I fail to see how a polymer made entirely of fluorinated alkyl substances is not a polyfluorinated alkyl substance. I'm not really sure how one could argue they're not if we ignore politics and just look at chemical nomenclature

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Re:The EPA is proposing that 'forever chemicals' be consider... by timr on Sunday February 04, 2024 @02:55PM (#39253741)
> I fail to see how a polymer made entirely of fluorinated alkyl substances is not a polyfluorinated alkyl substance.

It is a "polyfluorinated alkyl". The term is so broad as to be meaningless, and PFOA is wildly different, chemically and physically, than PTFE. One is a water-soluble acid. The other is an insoluble substance that is one of the most chemically inert things known to science.

It's like labeling something as "fluoride-containing" and panicking because your city water supply has it (which some people do, but I digress).

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Re:The EPA is proposing that 'forever chemicals' be consider... by hcurtiss on Friday February 02, 2024 @06:45PM (#39236069)
As it turns out, the definition of PFAS is hotly contested, with those advocating for increased regulation often also advocating for a very broad definition. https://www.bu.edu/sph/news/articles/2022/is-there-a-right-d...
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Re:The EPA is proposing that 'forever chemicals' be consider... by dataflow on Friday February 02, 2024 @09:22PM (#39237046)
https://chemsec.org/the-teflon-chemical-ptfe-is-often-touted...

"PTFE, or polytetrafluoroethylene, belongs to a subgroup of PFAS called fluorinated polymers"

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Re:The EPA is proposing that 'forever chemicals' be consider... by giantg2 on Saturday February 03, 2024 @12:29AM (#39237771)
Then you should add some sources and correct Wikipedia.
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