I've alluded to the fact that I spent many years working on a nation-wide(US) water testing project once and that I don't own the results, they were never published, and I can't specifically give away those results that I don't own. All of this recent talk about PFAs in water is absolutely killing me. This new water testing is going to take place over the next three years, and it's important to note that it's *only* talking about a handful of chemicals.
I've found that particularly US-based people really think their water is great and vastly overestimate how great it is. It comes out of the tap, you drink it and you don't die of waterborne illnesses. Woohoo. Really, it's an accomplishment.
But until you spend time in a water testing lab you don't really begin to realize how much isn't tested for in that water you drink and bathe in. It's just not possible.
People would ask me all the time "How do I get my water tested for everything?" You can't. Think of the story recently about how many chemicals are in plastics, for instance. 16,000-ish and over 4,000 that are potentially hazardous. Basically zero of those are tested for in any way whatsoever. To get something tested, someone has to care enough that it's there in the first place. Then someone has to create testing procedures and standards. Then there has to be a market for that test.
Let's JUST talk about PFAs. You know how many there are? Ballpark is ~15,000 different PFAs. You know how many are tested in this new EPA program? 25.
Now that we've established that, just how likely is it that testing will find PFAs in YOUR water in the US?
https://www.ewg.org/interactive-maps/pfas_contamination/
Pretty likely.
While I can't really talk about what states are likely to find if they honestly look, what I do talk about, and have for probably 20 years now, is what I did when I realized what's really in your water. I put in a whole home filter outside of our home to filter out a lot of stuff for showering and hand washing. No one so much as cleans vegetables here unless the water comes from the reverse osmosis system in our kitchen. Drinking water, ice, pasta water, fruit and veggie washing water, etc all comes from that.
I'm very sensitive to the fact that not everyone can do all of that. It's a step in the right direction that the EPA is beginning to do something about this, but it's far later than it should be and doesn't go nearly far enough. All I can say is that you should demand better, and not just about PFAs, but all contaminants in your water supply.
And before anyone asks, yes, the spring water on the homestead is about as clean as you can find anymore. Under 10 TDS and no contaminants that I've found to date. Again, can't test for everything even if you wanted to and had a million dollars to throw at it. It was a major selling point on the property for us.
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.
Wasn't that 3m data saying the PFAS in Aura masks was only in the straps? And only in some flavors of Aura?
Not where we would be breathing
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.
Most factories and plants have a good deal of teflon - it's in some roller bearings, it's some low-friction planar surfaces, etc. etc.
Please don't burn energy on this if it's not super easy for you, but on the possibility that it's no trouble:
I know you laughed off the idea of testing for all PFAS, but how might one go about getting water tested for just PFOS?
And, long shot, does your library happen to have any source for RO vs. activated charcoal filtration of PFAS?
Trying to convince some folks - including someone who wants to get pregnant, after recent miscarriages - to be a bit more careful with their intake. A hard line to walk because it's dangerously easy to come across as blaming.
I can't convince them to avoid SARS2 (yet) but they don't have the same mental blocks around environmental contamination.
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.
@BE even if I knew I was breathing in a dose of it by wearing a mask I would still rather breathe in forever chemicals than Covid.