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  • Hi, this is Kate from MinuteEarth.

  • Lead is poisonous and it can leach into water, so you probably wouldn't gulp from a cup

  • made of lead.

  • Yet today, hundreds of millions of us worldwide get our water from plumbing that contains

  • lead.

  • Seriously, humans?

  • How did we get here?

  • We've actually had a complicated relationship with lead for a long time.

  • Scholars first recognized its dangers in ancient times, yet for the next 2000 years, we relied

  • mainly on lead to transport our water.

  • After all, lead is plentiful, and since it has a low melting point, it's easy to extract.

  • It's a super-soft metal, so it can easily be formed into pipe-y shapes, and it can last

  • for centuries - far longer than other plumbing contenders.

  • Lead is such an ideal water-transporter that the wordplumbingliterally came from

  • the Latin word for lead.

  • And while people have known for a long time that lead could make us sick, it was tricky

  • to nail down how big a risk it actually was.

  • It can take years to see the effects of lead on our bodies, and even then, its symptoms

  • can be mistaken for lots of other maladies.

  • But what really *led* to confusion was that in some places, lead pipes didn't seem to

  • make people sick.

  • Generally, lead can leach right out of a pipe and into the water rushing through it, poisoning

  • people one refreshing drink at a time.

  • But in places where water has lots of dissolved minerals, a hard, scaly crust builds up inside

  • pipes, which separates the water from the lead, keeping most of it out of our cups.

  • By 1900, we had figured out these quirks and fully understood the dangers lead pipes posed,

  • but two thousand years of plumbing had given lead some serious inertia.

  • By then more than 70 percent of large US cities used lead water lines.

  • Pipefitters and plumbers still preferred plumbum for their plumbing work.

  • And in some places, the powerful lead industry worked hard to keep promoting lead pipes for

  • decades.

  • All in all, it took many countries until the late 20th century - or longer - to ban the

  • installation of new lead pipes.

  • But there were still lots of lead pipes already out there, and replacing them would be incredibly

  • costly and difficult.

  • But we could put to work one of the things that had initially confused us about lead

  • pipes; we started adding dissolved minerals to water that didn't naturally contain them,

  • artificially forming that protective crust that makes lead pipes safe...well, safe-ER.

  • Occasionally, disaster happens - like when a drought in England caused the protective

  • barrier in a town's pipes to crumble, poisoning hundreds of people when water started flowing

  • again; or when officials in Flint, Michigan neglected to add minerals to the town's

  • water, exposing tens of thousands of households to lead.

  • It's time to get over the cost and effort of removing and replacing all that plumbum,

  • so that safe plumbing is no longer just a pipe dream.

  • In the US, instead of replacing lead pipes, the Environmental Protection Agency has tried

  • to monitor and limit lead levels in drinking water.

  • But here's the thing: their flawed testing method systematically misses high lead levels

  • in water.

  • What's more, the lead limit the EPA has adopted isn't actually based on what's best

  • for human health in the first place.

  • These not-so-minor details mean that tens of millions of Americans are currently at

  • risk of lead poisoning.

  • For more information about what's actually going on here, you can check out Buried Lead;

  • the result of a collaboration by APM Reports and The Water Main, the sponsor of this video

  • and an initiative of American Public Media that's working to build public will for

  • clean, affordable, accessible water.

  • You can read the story at apmreports.org/water.

  • Thanks to the Water Main for helping us make this video, and for trying to make sure the

  • water we're drinking is plentiful and safe.

Hi, this is Kate from MinuteEarth.

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B1 中級 美國腔

为什么我们仍然使用铅管?!(Why Do We STILL Use Lead Pipes?!)

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    joey joey 發佈於 2021 年 04 月 30 日
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