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  • Human-made chemicals that were once considered the peak of our ingenuity have come back to

  • haunt us in a big way.

  • Theyre present in our soil, air, water... and that means theyre in us, too.

  • And we don’t know how to get rid of them.

  • But recent work promises a way to break down these compounds that most of us are exposed

  • to every day, and the solution involves plasma.

  • Thesezombie chemicalsthat never die are called Per- and PolyFluoroAlkyl Substances,

  • or PFAS for short.

  • Theyre a whole family of thousands of different compounds that are all based on the strongest

  • bond in organic chemistry: the bond between carbon and fluorine.

  • Because the C-F bond is so freaking difficult to break, PFAS have been used in tons of everyday

  • products around the world since the 1940s as a handy barrier substance.

  • These compounds are used as stain repellents, non-stick coating on cookware, and super-effective

  • firefighting foam.

  • Theyre also used in semiconductors, cellphones, vehicle manufacturing, really... theyre

  • everywhere.

  • But the very trait that makes them so useful is also what makes them difficult to break

  • downeven when you want them to.

  • And while some of them may not be dangerous, we're still not sure what their long term

  • effects are.

  • Several public health studies have shown that PFAS are hanging around in the blood and urine

  • of 95-97% of the U.S. population.

  • Theyre really hard for your body to get rid of, because you can’t break them down.

  • And that means that as we get older, the amount of PFAS in our bodies may only increase.

  • And you thought diamonds were forever.

  • Were still really trying to get a handle on what exactly theyre doing to our bodies.

  • Were pretty sure that two specific kinds of PFASPFO and PFOAare hazardous to

  • our immune systems and increase our cholesterol.

  • They may alter our metabolism, our fertility, and pose risks to fetuses, like low birth

  • weight.

  • And perhaps most alarming of all, there is evidence to support a possible link between

  • these PFAS and a higher risk of thyroid disruption and even cancer.

  • More research is needed to understand exactly how these compounds are causing these changes,

  • and what levels of which PFAS cause what changes, because honestly, were still figuring it

  • out.

  • But long story short: there are tons of them, theyre everywhere, and theyve been nearly

  • impossible to get rid of... until now.

  • A new project out of the Air Force Civil Engineer Center has developed something called the

  • Enhanced Contact Plasma Reactor, which is as exciting as it sounds.

  • The device uses argon gas to push the PFAS to the surface of a sample of contaminated

  • water.

  • It then uses electrodes on either side of the isolated PFAS to generate plasma.

  • Plasma is basically a big cloud of particlespositive ions and free electronsthat can knock other

  • things apartlike that super strong C-F bond.

  • The new plasma technology reduces the concentration of those two most dangerous PFAS to a safe

  • level for drinking, and does it faster and cheaper than some of the other options out there.

  • It’s a huge step because other methods for removing PFAS from contaminated water samples

  • just filter them out.

  • Then you have clean water, but you still have PFAS waste to deal with.

  • While this method instead actually breaks the PFAS down into their different parts,

  • making them easier to dispose of.

  • This is a super exciting solution to the super staying power of PFAS, but it may still be

  • quite difficult to apply this method to huge aquifers of drinking water.

  • So the team is working on scaling up and making sure the tech can be easily mobilized at scale.

  • Plus, it’s only one of several innovations that were gonna need... because what about

  • PFAS in our soil, and in our air?

  • Some other teams have demonstrated that soil microbes can eat and process a certain kind

  • of PFAS, so that’s a cool possibility, and many other teams around the world are working

  • on all kinds of innovations to make PFAS lessforever’.

  • Hopefully as we learn more about the effect of PFAS and how to deal with them, we can

  • better understand how to leverage all of their perks, but for a limited time only.

  • If you want to learn about another surprising plasma purification innovation, then check

  • out our video on a new virus filter here.

  • And subscribe to Seeker to keep up with all of the latest tech that's helping us clean

  • up our world.

  • If you have another environmental remediation topic you want to see us cover, let us know

  • down in the comments below.

  • And as always, thanks for watching.

  • I'll see ya next time.

Human-made chemicals that were once considered the peak of our ingenuity have come back to

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這種新技術可以消除我們飲用水中的有毒PFAS。 (This New Tech Could Eliminate Toxic PFAS From Our Drinking Water)

  • 29 1
    林宜悉 發佈於 2021 年 01 月 14 日
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