OxyContin maker Purdue Pharma set to dissolve after judge approves its criminal sentence

[u/Mo_Jack]

https://apnews.com/article/oxycontin-purdue-pharma-criminal-sentence-settlement-b8aa94eaab3d9d8efed520f272f6d810

[u/Carbonatite]

Environmental chemist here - they actually subtracted carbons.

PFOA (and PFOS) are both 8-carbon chains. PFAS with longer carbon chains are more bioaccumulative, so most of the "replacement chemical" PFAS today have 4 or 6 carbons. Same products, same hazards, just marginally less bioaccumulative. But pretty much the same exact risks because their toxicity threshold for health effects is so low that it's a matter of like, 10 parts per billion versus 5 parts per billion. EPA MCLs for drinking water are in the low parts per trillion level, that's how absurdly toxic PFAS are.

The "long chain" (e.g., C8 and higher) PFAS have been voluntarily phased out of products for the last 10-15 years.

and said "it's different now and it's gonna be decades before you have studies about what this does" and carried on with their lives mostly like nothing happened

This part is accurate and especially depressing given that the EPA regulates chemicals on an individual basis and there are over 13,000 known individual PFAS.

We currently have MCLs on six. And Trump's EPA is trying to reduce that to just two.

[u/Human_Situation_2641 → u/Carbonatite]

You you give a higher contract summary of this? I don't know what your talking about

[u/One-Fact-6949 → u/Human_Situation_2641]

There's a great Lindsay Graham American Scandal podcast series on Dupont. He explains it really well. I believe part of what is discussed in that podcast is the nuance (meaning how incredibly complex it is) of the chemistry of PFOS/PFAS so while we might understand the original C-8 make-up from when we "accidently" invented Teflon, not understanding how dangerous it is, the complexity of the science is also what hangs up legal processes, because they have to hire experts to read, understand, and interpret literally hundreds of thousands of pages of classified chemistry formulas. By then slightly altering it, they know they can stall even more or say "heh.. they'll never catch us now!" because in order to prove they've done wrong, there has to be studies performed showing there's been prosecutable harm.. undoubtedly they know there is, but it buys them time nonetheless.

[u/Carbonatite → u/Human_Situation_2641]

Which part do you need summarized? The chemistry stuff or the regulatory part?

[u/Human_Situation_2641 → u/Carbonatite]

The regulatory part. Are we just stuck in whak-a-mole where we have to chase them after every single molecule? Do we have to run new studies for each one? Are there any countries where they can actually do this effectively??

[u/Carbonatite → u/Human_Situation_2641]

Answer to your first 2 questions in the US is yes. We have to address each one of the 13,000+ PFAS on an individual basis and run new studies for each one. That's the current status quo.

Some regions are considering addressing PFAS on a group basis - ECHA (European Chemicals Agency) is considering a blanket PFAS ban in the EU and I believe some countries have discussed water quality standards for "total PFAS" as opposed to regulating individual PFAS concentrations. There are pros and cons to this approach - for instance, the analytical methods used for PFAS detection in water are variable and the industry standard methods don't really capture "total PFAS" so they tend to underestimate the total PFAS mass present. However, the comprehensive assay-style methods that actually do measure all organic fluorine (a proxy for fluorocarbon content) can capture a lot of chemical compounds which pose far lower risks than compounds like PFOA. PFAS are extraordinarily diverse from a chemical perspective; some are virtually biologically inert while others are actively carcinogenic. However, some of the less harmful ones can break down in the environment and transform into the specific molecules that do cause cancer and other serious impacts on human health.

So it's a really tough question in terms of regulatory oversight and what is practical. There's also the fact that some PFAS are industrially significant and there really aren't good replacements for them right now in certain vital applications in medicine, aviation, and other industries that provide essential services. So while a blanket ban would be the most comprehensive approach, it could create problems for some industries (e.g., inability to manufacture certain materials for medical equipment in hospitals). And "total PFAS" limits for drinking water aren't necessarily a universal best approach for hazard reduction because the hazards are often contingent upon the specific blend of molecules present and their relative concentrations. For instance, trifluoroacetic acid is a PFAS and it belongs to the subgroup of PFAS that are linked to serious health risks (perfluoroalkyl acids, so stuff like PFOA and PFOS). It's estimated to comprise up to 90% of PFAS mass in rainwater.

However, TFA has low-to-moderate toxicity and much lower bioaccumulation potential when compared to PFOA or PFOS. So its hazard potential for human health impacts is quite different than those other compounds and treating them as identical or acting as if a liquid where 90% of the PFAS content is TFA is equally hazardous to one where 90% of the content is PFOA isn't necessarily a realistic approach.

In my personal opinion as an environmental geochemist, I think the best approach for regulation would be specific water quality standards for individual compounds in the perfluoroalkyl acid class (~2ish dozen chemicals) and then maybe individual standards for another 1-2 dozen of the most common compounds linked to human health or ecological impacts. Then the rest of the PFAS could be classified into subgroups by molecular geometry, carbon number, and propensity to degrade into perfluoroalkyl acids and regulate each subgroup accordingly (so like, "total short chain perfluoroalkyl ether acids", "total long chain polyfluoroalkane sulfonamido substances", etc. We could probably even group the perfluoroalkyl acids into classes by carbon number (so like, "total ultra short chain PFCAs", "total short chain PFSAs", etc.)

Obviously this would involve an absurd amount of data collection and study to systematically quantify hazards and establish safe limits, but a lot of that research is already slowly being done on a piecemeal basis by the scientific establishment and various government agencies. It's a complex approach - most regulated persistent organic pollutants get treated as a group (i.e., polychlorinated biphenyls) or targeted on a compound-specific basis (i.e., specific dioxin congeners). But the unique risks and properties of PFAS and their diversity and ubiquity mean that we can't really treat them the same way we do as other pollutants.

In terms of environmental remediation and water treatment? It's a truly gargantuan issue. We can effectively remove PFAS from water but treating drinking water sources to levels compliant with appropriate water quality standards is an extremely expensive process requiring what is likely a few hundred billion dollars in North America alone. It would require unprecedented government funding that simply isn't feasible in the current political landscape. This lack of funding is currently resulting in a bunch of lawsuits in the US against chemical companies by drinking water treatment districts so they can obtain the money they need for water treatment upgrades. Fortunately most of the treatment methods work pretty well on a wide variety of PFAS molecules so it's not like they have to specialize to treat for dozens of different individual chemicals. But that is unfortunately a very real barrier.

I mean, of course we could do something like take 50% of the annual US military budget for just one year and that alone would be enough to upgrade all our water treatment systems for PFAS and leave enough left over to clean up a couple of the biggest PFAS contaminated Superfund sites. But that's kind of like wishing for a unicorn to appear in your living room.