[starwatch]

If you want more context on PFAS, I recommend this Veritasium video [0]. It expanded on my usual thought of "PFAS = bad," explaining why non-stick cookware is probably fine while other forms of PFAS are problematic. The video also covers the environmental damage caused by PFAS manufacturing.

[0]: https://youtu.be/SC2eSujzrUY

[Citizen8396]

The extremely toxic PFOA and PFOS are byproducts of manufacturing Teflon. After decades, we have managed to just barely regulate it. We don't know if these newer compounds will ultimately have similar effects. DuPont had reason to believe these original compounds were harmful, but they suppressed that fact in favor of profit. "Probably fine" is not acceptable, considering we can't meaningfully clean the stuff up.

https://en.wikipedia.org/wiki/Timeline_of_events_related_to_...

[ck2]

skiers have been putting teflon wax on their skis for decades now

it's in the snow, ground, and water-supply

forever

[usefulcat]

According to the linked Veritasium video, Teflon is not directly problematic, it’s the chemicals used to manufacture Teflon that are the problem.

[schiffern]

"Teflon" ski wax (fluoro-wax) contains PFOA impurities, which is that same problematic chemical. It's expensive to remove so most manufacturers don't bother.

https://skiracing.com/future-without-fluoros-a-complete-guid...

[cluckindan]

It’s also applied to skis by heating it, which breaks down the polymers.

[j4coh]

Veritasium seems to be frequently wrong or at least incomplete. I empathise, it’s hard to make definitive statements like that, but maybe at some point it’s better not to if you’re not sure and more about entertainment than anything else.

[kjreact]

That’s a bold statement to make that “Veritasium seems to be frequently wrong”. Can you list some of these many wrong statements that they make?

[j4coh]

Why leave off “or incomplete” when people can see it directly above what you misquoted? But sure, plenty of examples here: https://news.ycombinator.com/item?id=38779199. You can search on Google for Veritasium wrong (or misleading, incomplete, etc.) if you’d like more examples.

[kjreact]

The YouTube video in your link refers to a single Veritasium video regarding their coverage of Waymo autonomous driving. But I feel the entire video is invalidated by the fact that Veritasium clearly mentions that their video is sponsored by Waymo. As a viewer I already know that there will be bias because of this declaration. Veritasium isn’t hiding it, so what’s the issue?

On HN I’d hope to read insightful comments instead of ones making strong statements without justification and asking others to Google for examples. If you’re too lazy to type out them out it’s probably better not to post at all; this is not Reddit.

[kjreact]

How am I misquoting you? If you meant to say that Veritasium is frequently incomplete then just say that. No need to add the frequently wrong part at all. You’re implying something much stronger than what you intended; just to sway people’s opinion. But I didn’t need to write this because as you say people can just read your bias.

[horsawlarway]

It's not like this is going unnoticed either, though.

The International Ski Federation (FIS) now bans fluorinated wax in all their competitions, and this wax is explicitly called out alongside cookware in much of the legislation that's going around in places like CA/CO for PFAS bans.

[lm28469]

You forgot rain. Maybe one day people will remember we're just sharing one small planet, the air, the water, the food supplies, ... all the shit you dump/burn ends up in your food or water eventually

[alright2565]

What is the physical process that leads to PFAS ending up in the rain?

[titzer]

The planetary hydrological cycle.

https://www.bbc.com/news/science-environment-62391069

[citizenpaul]

Oh snap that was some good "the expert" energy.

https://www.youtube.com/watch?v=BKorP55Aqvg

Why cant we have parallel lines that intersect. Geometry.

[alright2565]

That article's only citation is a review paper, and it doesn't answer my question or substantiate your claim. It only covers how much PFAS is found in rainwater, and not how it got there.

The sources cited includes https://doi.org/10.1016/j.watres.2020.116685, which is paywalled, but the snippet of the conclusion that is shown indicates that a possible major cause is industrial emissions:

> As local sources were determined to be significant, the results imply that local action can have an impact on PFAS contamination in precipitation. A three-way ANOVA model determined that functional group, chain length, and location were significant predictors of PFAS concentrations

If you can get the full text I'd be very interested in reading about it.

[vel0city]

Sure, its probably at its highest concentrations right where its being manufactured or used heavily, but in the end its migrating just about everywhere.

https://pubs.acs.org/doi/10.1021/acs.est.2c02765

> n Figure 1B, the levels of PFOS in rainwater are shown to often exceed the US EPA drinking water health advisory for PFOS, except for two studies conducted in remote regions (in Tibet and Antarctica).

I don't think there are a lot of industrial emissions in Antarctica.

[titzer]

There's a journal paper (i.e. already reviewed and accepted) linked at the bottom:

https://pubs.acs.org/doi/10.1021/acs.est.2c02765

That paper alone has 61 references. There are plenty of papers to go read.

[pengaru]

> all the shit you dump/burn ends up in your food or water eventually

but most that shit doesn't survive the journey intact, being out in the elements and bombarded by the sun isn't kind to most things

hence the focus on "forever chemicals"

[lm28469]

But still a lot of things do, pesticides following the rain cycles is a good example. We're killing the biodiversity and ourselves with it. We already almost entirely rely on synthetically amending fields with petrol byproducts to feed ourselves, tomorrow we might have to manually pollinate crops when insects won't be enough to do the job.

PFAS are a problem, co2 is a problem, but we have dozens of other very big problems that are partially, if not entirely, obscured

https://usrtk.org/healthwire/banned-pesticides-found-in-clou...

[bossyTeacher]

> We already almost entirely rely on synthetically amending fields with petrol byproducts to feed ourselves

elaborate please

[tremon]

https://en.wikipedia.org/wiki/Haber_process

> Nearly 50% of the nitrogen found in human tissues originated from the Haber–Bosch process. Thus, the Haber process [enabled] the global population to increase from 1.6 billion in 1900 to 7.7 billion by November 2018.

[NetMageSCW]

I assume that means we have to use fertilizer to ensure we can produce enough food crop.

[Zigurd]

Future archaeologists will wonder that we first fouled our nest from edge to edge with lead in gasoline, and then there's that radioactive layer, and following immediately after the forever chemicals layer.

[pengaru]

The anthropocene, aka the petroradiata layer

[SirMaster]

But you can filter out PFAS from water...

[cyanydeez]

you can filter anything out of water...you're just arguing end users should bare the cost of billion dollar corporations doing whatever they want.

The filtration at the levels we're talking about would add thousands of dollars to every household everywhere, all at once.

Talk about something that just is a bit more than, "but you can filter it".

[Bjartr]

Not saying it's a good approach to solving the problem, but surely you'd want to do the filtering at the water utility level. It would be a lot more cost effective that way.

[tristor]

It probably can't be effectively filtered at utility scale. There are only a small number of effective filtration methods and they basically coalesce to either distillation or reverse osmosis, neither of which is effective at utility scale. The other side of that is that both methods concentrate contaminates when removing them, and distillation puts some contaminates into the air, which means neither is a panacea even at residential scale.

The largest reverse osmosis plant in the world produces 165MGD of water, which is less than is required for any of the top 10 largest US cities, while primarily being used purely for desalination (SWRO). At the levels of filtration and membrane size required for removal of PFAS, it would nearly be impossible to cost effectively filter 200MGD+ of water for a major city.

[trainsarebetter]

Okay so how are you going to filter all the water in every water shed, pond, lake, estuary, etc?