A Concerned Scientist @BE@qoto.org

I'm trying to rent an AWD cargo van to move a few pieces of larger furniture and I'm finding that all of the rental places that have them, put them behind a "call for details" so you can't reserve them online. As soon as I call they ask why I need an AWD or 4WD since it's winter time. I say that I'm moving off grid and I'm up a dirt "driveway"(call it a road and they immediately hang up on you) and they all freak out. "Take it off of the paved road and you're violating our terms of service!"

I'm actually going to be brief here. Shocking, I know.

https://www.nytimes.com/2024/05/28/climate/pfas-forever-chemicals-industry-lawsuits.html

I think these lawsuits will ramp up. I've been trying to get someone I know who's suffering, and has plenty of money, to start one himself.

I also think, based on discussions with actual lawyers previously, that there will be a day in court where in one room lawyers are saying, "Sure, you're unwell, but, how do you know that's from PFAs and not COVID?" While lawyers in the next room over are saying, "Sure, you're unwell, but how do you know that's from COVID and not PFAs?"

Just a reminder to check your local wastewater testing if it still exists. Ours does not, but the two closest to us on https://data.wastewaterscan.org are both straight vertical lines now. This new variant's wave looks like it's likely to be a big one. At least locally, brick and mortar schools are mostly finishing up this week. Maybe that'll alleviate some of the pressure.

@datum

I know you're scientifically literate, so rather than dumbing it down some, tell me if this answers your first question:

https://www.asdwa.org/wp-content/uploads/2021/02/ASDWA-PFAS-Lab-Testing-Primer-FINAL-02032021.pdf

If not, definitely ask more questions.

The basic answer to the activated charcoal vs. RO from my standpoint is two-fold.

One, in short, I've seen various tests with some different results. I think if you think about activated charcoal like column chromatography, length, time and temperature all matter. I've seen various numbers coalescing around 80-ish percent, though, and that's probably a fair number, but, real life results will differ.

Specifically, I've sent this to a couple of people because the supplementary data to this paper lists out some exact brands of filters that they used under real life conditions(it's not too hard to get the number you're looking for, for just one chemical in the lab). I stumbled on it looking for something else recently, and Berkey filters must be popular because at least three people asked me about it and they tested three of them, for instance.

https://pubs.acs.org/doi/suppl/10.1021/acs.estlett.0c00004/suppl_file/ez0c00004_si_001.pdf

Two, I always have to say this even if you know it, RO's just more comprehensive. There's always stuff that you just don't know about in there, and RO's going to get more of it.

Honestly, the Swiss cheese approach works here, too. I have a whole home filter that filters everything coming into the house, and THEN I run the drinking/cooking/dishwashing/ice making water through RO.

@NilaJones

I have read that the Aura-specific thing was about the straps. I don't know if that's fact? I just haven't seen a source on it. I am assuming that it is, though, and that's part of why I'm attributing it to manufacturing contamination rather than intentionally making the mask, itself, waterproof with PFAs.

More in general, the study that included just 1 N95 alongside 6 cloth masks and a firefighting mask wasn't Aura specific, but, did give tenth of a microgram precision numbers. So I thought that would make a good test case for scale.

The fact that more or less random cloth tested higher for PFAs than the N95 tells me that it's likely manufacturing contamination with the N95. Manufacturing parts are a mess in that regard.

Math time!

The paper cited above about PFAs in masks was designed to study their accumulation in dumps. I don't want to gloss over that, but, I'm going to anyway.

On an individual mask basis, you have to do some math to figure out how much PFA contamination you're talking about, because they were looking at it per square meter of mask materials.

The N95 in the study tested out at 15.2 micrograms per square meter. Your mask is obviously not a square meter.

I'm going to make an assumption and do some rounding here, just to get a ballpark number.

I pulled a 3M Aura off of a hook by our door(my wife wears one to get the mail, or slap on if the FedEx guy keeps knocking and won't go away) and a quick measurement tells me it's around ~6" x 8" or about 300 square centimeters. There's 10,000 square centimeters in a square meter, so, one Aura mask is roughly 3% of a square meter.

15 * 0.03 = 0.45 micrograms of 3 PFAs combined on a single mask. Most limits for PFAs are listed in ppt(ng/L) or ng/kg body weight. So, 0.45 micrograms is 450 nanograms.

So, in that same ballpark, what does it mean?

*I am not saying that there is a "healthy" PFA dose. Your body struggles to get rid of it and it doesn't ever break down.*

The European Food Safety Authority says that the tolerable weekly intake of PFAs is 4.4ng/kg of body mass. That would mean ~220 pound person could eat their N95 every week and stay within the limits(please don't).

The state of Virginia says that your water can legally contain 150,000 ng/L. In Virginia you could drink 333 N95's worth of PFAs continually(please don't).

Under the new EPA guidelines that will go into effect, maybe, years from now water must be under 4ppt. So, one N95 might contain the amount of PFAs in a month's worth of your drinking water if you drank 3L a day, and if that goes into effect and is enforced.

What does it mean for what you're actually exposed to already?

In a study some paints had upwards of 700 ppm total Fluorine. If, as expected, the PFA in the paint formulation was 6:2 FTOH, that would be around 50 ppm of that PFA, or 50,000,000 ppt. Thank goodness we don't ingest paint, but, I'm willing to bet we're all surrounded by it. How well encapsulated is it?

https://habitablefuture.org/wp-content/uploads/2024/03/97-pfas-in-paints.pdf

In a bad scenario, my friend who is now facing kidney failure has been drinking neighborhood water that was tested at ~59,000 ppt in 2016 for a couple of decades, or so. He may have been drinking upwards of 180,000 nanograms a day. That's the same as ingesting 400 masks worth A DAY. I do not recommend this.

https://www.ewg.org/interactive-maps/pfas_contamination/#about

Even in rain water, tested amounts of PFAs were between 1 and 40 nanograms per liter in urban environments, or, often upwards of an N95 masks worth of PFA for every 10L of rain water.

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

Yes, there's studies that absorbing PFAs through the skin is similar to ingesting them.

https://www.sciencedirect.com/science/article/abs/pii/S0278691520300016

If the data we have on N95's is in the right ballpark, it's just not high on the spectrum of PFA concerns in my opinion.