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Have you or a loved one been  diagnosed with mesothelioma? Industrial exposure to asbestos may have put you at risk of this rare cancer. If you believe you’re entitled  to financial compensation, call 1-800-SUE-THE-PANTS-OFF-EM for extremely unbiased legal advice.

So, for legal reasons, I am not  a lawyer and this is a joke. I can’t help you sue anybody  if you have mesothelioma, but I can’t be the only one who  remembers those commercials, right? I can tell you some good news, though.

We’re making big progress  towards making asbestos really, for real illegal in the United States. Because yes, one major type  of it was still allowed. The reasons it was still around were… not good, but they were reasons.

Let me explain. [♪ INTRO] As of March 2024, the US  Environmental Protection Agency is banning the use and import of a  type of asbestos called chrysotile, and phasing out its use in industrial facilities. Congress passed the legislation in 2016, and it’s finally being implemented. Chrysotile is already illegal in the EU and more than 50 other countries.

New uses and imports of other  types of asbestos have been generally banned in the US since 1989. Though there are some frustrating loopholes. Even so, how did this other  type sneak under the radar?

To explain, let’s take a look at asbestos itself. Asbestos is strong and  fire-retardant, so back in the day it was used in loads of products,  including water supply lines, housing insulation and brake pads. In its heyday in the 70s there  were over a hundred million tonnes of it mined every year in the US.

Asbestos is a naturally-occurring fibrous mineral. But just because it’s natural  doesn’t mean it’s good for you. It’s made mostly of silicon, but the  other elements that make it up vary, giving us a variety of  different types of asbestos.

Amphibole asbestos includes  crocidolite and amosite. They have brittle, needle-like  fibers, and were used for tiling and various types of  insulation, including in homes. They’re the type of asbestos  that was already banned.

Well, again, loopholes, but theoretically banned. Chrysotile asbestos, which has  curly fibers, was thought to be less dangerous than its cousins  in the amphibole family. Chrysotile is the most  widespread asbestos in use today.

It’s used for brake pads, asphalt,  and plastics among other things. The problem is, both types of asbestos fibers get into your lungs and can’t  be cleared out by the body. They tend to collect in the  alveoli, the tiny sacs in your lungs where air gets exchanged with the blood.

This is as bad as it sounds. Asbestos fibers are abrasive and can lead to lung damage and scarring. Also, immune cells in the lung  are often smaller than the fibers, so they can’t help break them down, and that makes the immune system  panic, leading to more damage.

All this makes it difficult to  breathe, a condition called asbestosis. And asbestosis is just the start. Asbestos also increases the risk of lung cancer.

At the cellular level,  asbestos fibers increase levels of certain cancer-promoting  proteins, among other things. One study showed that asbestos exposure led to a 5-fold increase in lung cancer. But, as you already know if you’ve  seen those corny legal ads on TV, asbestos is especially infamous for  its association with mesothelioma.

Mesothelioma without asbestos  exposure is pretty rare. Mesothelioma is a cancer that affects the cells lining the organs’ exterior,  in this case the lungs. Yup, the asbestos fibers are  able to travel all the way to the outer lining of the lung  and mess things up there too.

So, if amphibole asbestos has been banned, but we’re only just getting around to chrysotile… is it less cancer-y? Well… industrial workers who work with chrysotile still have higher rates of  lung cancer and mesothelioma. Unfortunately, chrysotile  is commercially important, so that means there are motivated interests trying to show it’s less harmful than amphibole asbestos.

There have been people who have fought really hard to keep chrysotile legal. To explain the cancer rates  without incriminating chrysotile, something called the “amphibole  hypothesis” came into being. Basically, it hinges on two premises.

One, that chrysotile is safer than amphibole. In lab and real-world studies,  lung tissue accumulates more amphibole than chrysotile,  relative to the amount of exposure. This apparent lack of persistence in the body has been touted as evidence  that chrysotile is safer.

And two, that all chrysotile is contaminated with a little bit of amphibole, which is to blame for any increased risk in cancer. Does chrysotile deserve its free pass? Well, there seems to be a grain of truth here, which is that chrysotile  can be cleared by the lungs more quickly than amphibole fibers.

Unfortunately, these chrysotile fibers can still do damage before they get moved along. And chrysotile on its own has been shown to cause mesotheliomas and lung cancer. So there’s no way to make chrysotile asbestos safe for the people who work with it, and it isn’t worth trading their safety to have it as a commercial product.

However… we do owe asbestos  a little bit of thanks. It’s used in the production of chlorine, which we use to disinfect drinking water. And I don’t mean like fancy bottled water.

If you get up and turn on your sink right now, that water’s probably safe because of chlorine. Chlorine is produced by electrolysis. You basically run electricity through salt water, and out pops chlorine and caustic  soda, aka sodium hydroxide.

When zapping the salt water, the  positive and negative electrodes are separated by a membrane or diaphragm which is permeable only to specific molecules. That diaphragm has to be durable and resistant to the harsh chemicals involved  in chlorine production. Asbestos is one good material for that diaphragm, but it’s not the only option.

Some plants use membranes made  of fluoropolymers such as Teflon. This option comes with its own set of challenges, since fluoropolymers could potentially release polyfluorinated substances,  aka PFAS, into the environment. What did they use in the days before fluoropolymers and asbestos, I hear you ask?

Great question. Mercury. It was mercury.

Having chlorine is kind of essential  to the drinking water supply, so are fluoropolymers really the least horrible out of a lot of horrible options? For now yes, but there’s hope! A paper published in 2018 presented a way to produce chlorine without any diaphragm at all.

It’s still in the R&D phase, but hopefully will mean that one day this technology can be membrane-free. Regardless, we definitely don’t  need asbestos specifically. 8 chlorine facilities in the US that still use asbestos diaphragms will be phasing them out over the next decade or so. The majority of facilities  have already swapped over, so the drinking water supply  shouldn’t be in any danger.

An estimated 255,000 people die of asbestos-related disease each year,  nearly 40,000 of them in the US. Banning asbestos really is life or death. We finally have both the technology and the political will to get rid of the stuff.

But my money’s on the cheesy commercials sticking around a while longer. Thanks to EnergySage for  supporting this SciShow video! EnergySage is all about  helping you create a cleaner, more sustainable, more resilient home.

EnergySage helps people go solar with confidence. By installing solar panels,  your home can help avoid three to four tons of carbon emissions each year. It’s easier than planting over 100 trees annually.

And it’ll cut your electric bills. Over 1 million people have used  EnergySage to shop for solar, heat pumps, battery storage, and more. EnergySage’s simple marketplace and free, expert Energy Advisors make it easy to confidently shop for the right clean  energy solutions for your home and save 20% compared to going it alone.

They also have educational resources about other clean energy options  that might be right for you, like participating in a community solar program. You can join the movement towards  a planet powered by clean, affordable, and reliable energy  for all at EnergySage.com. Thanks for watching! [♪ OUTRO]