Tldr;
In 2022, a team at University of California at Riverside discovered that blasting wastewater with special “short-wave” ultraviolet rays causes PFAS chemical bonds to break down without creating harmful byproducts.
this post was submitted on 06 Jun 2024
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Don't we already filter municipal water and make sure all of this stuff is below some level of ppb?
I'm just going to give a quick overview of what wastewater treatment is and does.
The basic idea is that you can have something like a can of 7-up, it looks clean, but would kill a fish dead. It's got loads of dissolved sugar, and if you dumped it into a river, microbes would go nots on the sugar, sucking out all the oxygen as they grew, and causing a boatload of other problems.
But you can't filter dissolved sugar. I mean you can but it requires a highly specialized filter that would imeaditley foul is wastewater. And we're not just talking dissolved sugar, there's a whole range of everything in there.
So we do something very simple: we let the 7up grow moldy. 7 up would go through a coffee filter, but mold wouldnt. We let the mold suck up the sugar, then seperate that.
In reality it's a bit different but that's the idea. We grow a ton of microbes, let them suck everything out, then move them to another tank where they all stick together and settle to the bottom. The result is that the liquid at the top of the tank is clear, and free of anything dissolved as the bugs ate it all. (how we then get rid of all of that bug mass is whole other thing but basically we squeeze all the water out we can and it becomes dirt).
The problem with stuff like pfoas or any other micropollutant is that the bugs aren't that interested. And they're at such a low concentration it's incredibly hard to get such a small amount out of millions of gallons every day.
Wastewater treatment was meant to mimic natural ecology so that when it was discharged we didn't overwhelm the environment. If you poop in the woods, it's probably not a problem. If everyone poops in the same area of the woods... The woods are going to look different and not in a good way. We solved that problem, but not the one of what to do when the poop is "radioactive".
One last note: what I described above is secondary settling (letting the bugs settle and taking the liquid off the top). There ARE filters to seperate the bugs from the liquid, but they are no where near selective enough for specific compounds. Again, think coffee strainer.
In the US, a limit was only imposed in the last year. It only goes into effect in 2027. Before then, all there was was an EPA recommended limit in drinking water.
Nope, not PFAS. Few places have filtration sufficient to address them, from my understanding.
Systems that were already using activated carbon or ion exchange for organics removal may have some treatment capacity, but otherwise the first systems specifically for treating drinking water are being designed and constructed now. There are contaminated sites that already have treatment or containment in place.
This is very interesting. Currently, most ion exchange systems that remove PFAS have to dispose of their brine as hazardous waste, which is very costly and doesn't necessarily destroy PFAS - in Florida, for example, they inject the brine into a deep aquifer.
A lot of novel technologies target PFAS destruction in these concentrated waste streams, but often further concentration is required before you can effectively destroy PFAS with advanced oxidation processes. If they could use low-UV to destroy it without further concentration or additional chemicals (beside the salt already used to regenerate the resin), ion exchange would become a much better solution for treated PFAS contaminated water.
Tell me when they have a way to remove it from my cell supply
donate blood. Firefighters (who train with hazardous PFAS foam/liquids) were shown to have lower levels in their blood stream if they donated blood regularly.
Give blood.
Or plasma which you can donate more often
Or platelets every two weeks, woo!
Does that remove pfas, though?
Looks like that one hasn't been specifically researched. But where I go they do "Platelets Plus," so as you're eligible they take an additional bag of either red cells or plasma. So, unless the all toxins are all in the white cells, it should do the job.
They do leave the body over time, but the half life is very long, like 3-10 years depending on the specific one.
Blood levels of many of them have fallen a lot since the year 2000ish as some were phased out, though of course there's dangers of more being made.
https://www.atsdr.cdc.gov/pfas/health-effects/us-population.html
There's also new rules going in effect 2025 to require them to be removed from tap water if present, using a different process called ion exchange. The method described in the article is a way of destroying them once they're removed, so a way to treat high pfa level waste basically.
https://www.atsdr.cdc.gov/pfas/health-effects/us-population.html
Horrible how multiple companies like 3M and Dupont were covering up their dangers for years. $10 billion doesn't seem like nearly enough in damages.
https://time.com/6289893/3m-forever-chemical-pfas-settlement/
Especially when the costs of keeping it out of affected drinking water systems alone is expected to be $1.5 billion, per year.
Yeah, it absolutely astounds me that they polluted the entire world and poisoned everyone and everything within it, and then the people are footing the bill for trying to cleaning it up. And that's only our drinking water, not all the plants and animals we eat all the time that have it in them in probably huge amounts. AFAIK there is no plan for that at all so our cells will still be swimming in them.
3M and others should be taken over by the government and turned into nonprofits where 100% of their profit goes to cleaning up the world.
So, uh, you weren't around for regular (leaded) gasoline? We humans are slowly figuring shit out. Given that we took a couple hundred thousand years to get past stone tools, and given what we've achieved in the last 100, we're doing sorta OK. Wish I could see the world in 200-300 years.
I get that there are lessons learned for new advances in technology and society, but companies like DuPont and 3M knew about this and hid it. Then when legislation comes out banning chemicals they use, they change basically one atom in the molecule to avoid the regulation and keep going. They aren't honest mistakes.
Well there will be way fewer people.