Lead Limited Brain and Language Development in Neanderthals and Other Hominids?

today.ucsd.edu

95 points

gmays

a day ago


64 comments

8bitsrule a day ago

Conceivable. And not just that far back. It's been thought that Beethoven's deafness was largely the result of the way wine was stored back in the 18th century.

And what did we learn from history? "The federal government banned the use of leaded pipe and solder in new plumbing systems in 1986, but many remaining pipe networks in older cities and homes predate the policy; the EPA estimates there are still 6 to 10 million lead service lines across the country." - https://greenyplace.com/when-did-they-stop-using-lead-pipes-...

  • userbinator 18 hours ago

    It was known long ago that lead (and other) water pipes develop a passivation layer due to minerals in the water, and the water is adjusted to do so if it doesn't naturally, but everyone knows about the case of Flint, Michigan where they didn't.

    • AdamN 16 hours ago

      Yeah those types of second order problems are really tough in low-intelligence bureaucracies. 1/ Lead is good for pipes!, 2/ lead is bad for health!, 3/ ok we've ripped out half the pipes but it turns out that when we control the mineral mix in the water we can mitigate the lead contamination from pipes that are hard to replace, 4/ let's do something cheaper and not do any due diligence and forget that 3 was done some time ago.

      • IAmBroom 10 hours ago

        5/ because it's only poor blacks anyway.

  • _glass 17 hours ago

    Yes, in Hamburg, Germany there are a lot of lead pipes still. When moving there I got to find this out by a letter from the government, that I should know that I have many times over the limit drinking water which I was consuming. I was always telling others to drink the safe tap water ...

    • AdamN 16 hours ago

      Funny. If you say that kind of thing in some of the German subreddits they'll run you out with pitchforks - "Germany has the best water in the world!" is the refrain.

      • ubercore 15 hours ago
        2 more

        Norway checking in, moved here from the US, and have family in Germany. Norway water is definitely my preference.

        • IAmBroom 10 hours ago

          "Preference" is not safest.

    • manmal 11 hours ago

      Why did you tell others to drink tap water if you haven’t verified it’s safe?

      • mjh2539 11 hours ago
        2 more

        Because in the first world it is reasonable to believe that the tap water in major metropolitan areas is potable.

        • manmal 8 hours ago

          I'm a tap water drinker myself, but only after moving away from a city where water from other areas had to be imported to reach safe levels (according to EU regulations) because several garbage deposits of thousands of tons leaked for decades unhindered:

          Almost 2 million tons of garbage, among that 40k tons of toxic waste: https://de.wikipedia.org/wiki/Fischer-Deponie

          1 million tons aluminum & other stuffs: https://www.fcp.at/de/projekte/details/sanierung-altlast-n6

          One might imagine that diluting such water to reach "safe" levels is not as healthy as water that never saw a toxic waste dump.

          It's also not the case that tap water is always safe, even if it's declared to be. During hot summers, there's very often bacterial contamination, requiring addition of chlorine or other antiseptics. But until that is caught, some days might go by.

  • rangestransform 4 hours ago

    Chicago has so much lead pipe because “lead is so dangerous that only union pipe fitters can work with it”, and the pipe fitters union lobbied to put in more to create more work for themselves. Union leadership should’ve went to jail for that

  • Modified3019 13 hours ago

    Avgas still has lead in it unfortunately.

    • tastyfreeze 10 hours ago

      It is also not used by many airplanes.

  • charcircuit 18 hours ago

    I think it's ridiculous that landlords are able to rent properties that will give tenants lead poisoning as long as they provide a warning. I have a feeling that many people think tbe warning is just for legal liability and don't realize that their landlord is knowingly poisoning them.

    • potato3732842 14 hours ago

      Nobody is being "actively" poisoned except perhaps the consumers of your rhetoric.

      The lead develops a layer that keeps it from dissolving into water (much like aluminum develops an oxide layer) and won't hurt anyone as long as the water source doesn't pull a Flint. This is true for pipes both in houses and city pipes upstream.

      Is it more dangerous than not, yes. But it's not really an "active" problem.

      • charcircuit 8 hours ago

        >Nobody

        Anecdotaly, a landlord tried to rent me an apartment with lead. After receiving the warning that complex was built before lead was banned for construction, I asked if they used lead pipes and was ghosted. When I tested the water and it came back positive with lead.

    • bell-cot 16 hours ago

      Unfortunately, "lead in the water" is not a boolean, and is extremely dependent on things the landlord doesn't control - especially the chemistry of the municipal water supply. But our legal system makes it easiest to sue the landlord.

      Sure, you could rip out all the old metal pipes and replace them with (say) PVC. Even handwaving the expense and issues of that - did you just replace "lead" with "microplastics"?

      • charcircuit 8 hours ago
        2 more

        >is not boolean

        There is a concentration of it where it becomes harmful.

        >dependent on things the landlord doesn't control

        They have the ability to filter water.

        • bell-cot 3 hours ago

          > There is a concentration of it where...

          Unfortunately, lead seems to follow a "anything above 0.000000000000% is harmful, though more is worse" rule.

          > They have the ability to...

          True, but there are a lot of filter-worthy things which can be found in drinking water -

          https://www.epa.gov/ground-water-and-drinking-water/national...

          - so how much filtering, for which contaminants, should they have to do? How often should they have to re-test the (probably municipal) water supply, to verify that their filtering is doing the job? And how much will they mark up the price of water for their tenants, to cover the expenses of all their extra filtering and testing?

    • quickthrowman 8 hours ago

      Lead service lines are like asbestos, they’re fine if they aren’t disturbed. A layer of minerals builds up on the inside. It’s still best practice to replace them, but excavation and plumbing for one house can be $15-20k.

      The city I live in is replacing lead service lines across the entire city and offers low interest financing for homeowners.

      Crucially, the water treatment chemistry needs to remain consistent. Changing the process is what caused the lead pipes in Flint to start leaching lead into the water. They changed water suppliers during a budgetary crisis.

      From the Wikipedia article:

      > In April 2014, during a financial crisis, state-appointed emergency manager Darnell Earley changed Flint's water source from the Detroit Water and Sewerage Department (sourced from Lake Huron and the Detroit River) to the Flint River.[7] Residents complained about the taste, smell, and appearance of the water. Officials failed to apply corrosion inhibitors to the water, which resulted in lead from aging pipes leaching into the water supply, exposing around 100,000 residents to elevated lead levels.[8] A pair of scientific studies confirmed that lead contamination was present in the water supply.[9][10] The city switched back to the Detroit water system on October 16, 2015.[11] It later signed a 30-year contract with the new Great Lakes Water Authority (GLWA) on November 22, 2017.[12]

      https://en.wikipedia.org/wiki/Flint_water_crisis

  • cyanydeez 12 hours ago

    Most likely leaded gasoline from the rise of cars is our bariatric les fascism.

    • Loughla 12 hours ago

      What does that mean?

  • j45 19 hours ago

    Meaningful in-home water filtration increasingly seems pretty much mandatory.

    The degree of water filtration often requires about having to learn about re-mineralizing.

    • 05 13 hours ago

      > The degree of water filtration often requires about having to learn about re-mineralizing.

      You can drink distilled water all day every day, you get all the minerals you'd ever need from food. Remineralization post-filters are purely for better taste (subjective of course).

      • oneshtein 12 hours ago

        I ate salty products like crazy after year or two on pure water. My doctor told me to drink mineral water or tap water instead of pure water — the problem is gone.

      • j45 6 hours ago

        Drinking distilled water can create micro deficiencies that can contribute to things like brain fog, etc depending on the type of water you normally have.

        Drinking distilled water strips your body of things that naturally are in water, because no fresh water lake, river, etc is distilled water.

        Another key part of distilled water is that it also has fewer electrolytes. Electrolytes to a good degree are our friend. If water already has a bit of magnesium in it, it's helpful, everyone just gets it.

        I respect if it's working for you but I have met many folks who it didn't work for.

        Remineralization felt like a pain, but like most things it doesn't hurt to try and collect your own experience rather than understand everything before beginning.

        Since drinking water can be location based, some water may have more calcium naturally in it, or something else, etc.

    • IAmBroom 10 hours ago

      This is the internet. It is global. In-home water filtration is a minority situation in the US.

      • j45 6 hours ago

        Trying to understand your point.

        Water filtration seems to exist plenty inside the US and outside too.

p0w3n3d 15 hours ago

I was taught by parents to not pour hot water to the kettle, because the water heater might have lead pipes and cold water was omitting them. I wonder was it the case...

  • dpark 9 hours ago

    It’s more that hot water will leech more lead from whatever lines do you have, including in the water heater itself. The biggest concern would generally be lead solder. There’s no reason you would have lead lines for hot water and copper lines for cold.

    Also the hot water sits in a tank (in most homes) full of scale and may just taste worse.

  • IAmBroom 10 hours ago

    That might have been true locally, but you need to know the actual lead levels (which can change with infrastructure changes) in cold and hot water to know for sure.

    I replaced my hot water heater and supply pipes myself, so it has no more lead than the cold. They're currently tearing up my street to replace the lead in supply lines, so... everything will hopefully improve here.

  • roryirvine 7 hours ago

    I grew up doing this, though in our case the old heating system drew water from a tank in the roofspace where it could have been left sitting for a long time before being used.

    We were also taught to run the cold tap until it got really cold (indicating that fresh water from the mains was coming out) before drinking from it.

    Weirdly, I remember that we had our water pipes replaced with plastic and the heating system modernised when the house was renovated in the late 80s, but we still persisted with those habits afterwards...

    Australian friends still get super upset with me for wasting so much water - they have water conservation drummed into them from an early age, so tend to see running the tap even for a second or two too long as being some sort of terrible sin.

  • quickthrowman 8 hours ago

    Your parents were correct about the advice, but wrong about the reasoning. Possibly hot water leaches out lead easier, but it’s more about water sitting in a hot water tank.

    Hot water in a home usually sits in a metal tank that is full of scale/minerals. Once the sacrificial anode is used up (maybe 1% of people actually replace their anode when needed), the tank begins corroding.

    Hot water is for washing things, cold water is for consumption.

IAmBroom 9 hours ago

> “One possibility is that they were looking for caves with running water inside,” Muotri said. “Caves contain lead, so they were all contaminated.

I'm not buying this claim that all caves contain lead (throughout Europe, at least). Europe is not a wonderland for lead mining. Southern Missouri (USA) historically produced a significant amount of the world's lead supply, but no early hominids evolved there.

And I don't understand the figure early in the article. It seems to show that Homo sapiens evolved with quite a lot of lead exposure, while H. neanderthalis did not - so they didn't need our "immunity" to lead.

Finally,

> “If all humans have this newer mutation in all corners of the world, very strong genetic pressure must have selected for it in our species.”

Or, it was present in the bottleneck die-off of H. sapiens 800kya, and hasn't mutated since. The added complexity in organoids in the lab is interesting, but the mere presence of a single base pair in a gene doesn't guarantee that it is genetically important.

> “The FOXP2 gene is identical between us and the Neanderthals, but it's how the gene is regulated by NOVA1 that likely contributes to language differences.”

That at least does underline the importance of this genetic difference.

hyghjiyhu 10 hours ago

What seems off to me is that lead (at that level) must have been a factor in the natural environment for a very long time, so it's strange for a tolerance mutation to be recent.

Ericson2314 10 hours ago

We gotta clone some neanderthals to really figure out!

(No I don't mean lead poison them, I mine figure out what they are like without lead.)

rendall 18 hours ago

Seems implausible that the entire taxonomic family of Homidae would be exposed to neurotoxic levels of lead because of cave water. I'm not convinced. Something is off, here.

  • stevenwoo 11 hours ago

    Somewhat coincidentally I am reading "The Language Puzzle" and the author puts forward the theory that based on the tool evidence left behind that the language development of Neanderthals was as much as they could do with their brain physiology and environment, i.e. there was no improvement in stone tools over their entire history versus the other human population evidence we have at close to the same time and that the improvement in stone tools in other populations had to be verbally communicated. There of course is the bias in the evidence we have may not be fully representative and this theory is not mutually exclusive with the genetic argument in the article.

  • rotis 16 hours ago

    Agreed. Lead main source in nature is galena, which is relatively nontoxic. It rarely occurs in metallic form.

    • daviesiesies 9 hours ago

      It is ok to handle galena if you don't eat with your fingers. But it is highly toxic if swallowed or inhaled.

dr_dshiv 12 hours ago

Incredible. How did they know to search for this relationship! So many dependencies.

Now, how can I get my family tested for lead exposure? I worry about the old silverware…

JoelMcCracken 20 hours ago

Do most people just not know how to write an interrogative sentence anymore? It is wild to me how often these fragments of questions appear on the front page.

I use this form sometimes myself in a dialogue, as it fits that context. But as an isolated story title, I invariably end up reading the whole sentence several times, trying to parse it.

  • bawolff 20 hours ago

    I think Hacker news removes "filler" words from headlines, which is why it is so weirdly phrased. The original headline is different.

    • floam 20 hours ago

      HN doesn’t do it but it does have a character limit: go to the submission form and paste the original title (“Did Lead Limit Brain and Language Development in Neanderthals and Other Extinct Hominids?”) and you’ll see too long.

      People lazily remove words until it fits instead of reworking the whole thing sometimes.

      • krapp 20 hours ago
        4 more

        HN does actually have automatic text filters to remove "extraneous" words from titles, even when they do fit. People have complained that the filters are too naive and sometimes destroy necessary context but for whatever reason the mods consider it necessary.

        • floam 20 hours ago
          2 more

          Oh, TIL. I guess in this case it couldn’t have been since you can’t submit if too long but I was unaware.

          • krapp 20 hours ago

            Could be one or the other, or both, but the filter's definitely there.

            Fair warning HN also automatically replaces submitted links with canonical links despite most canoncial links pointing to the original domain for SEO purposes. There is no warning or feedback for any of this, you're just expected to notice and edit your post after the fact.

        • andsoitis 19 hours ago

          You can edit the title after submission

      • floam 20 hours ago

        I personally would have tried:

            Did lead limit extinct hominid and Neanderthal brain development and language?
  • JoelMcCracken 5 hours ago

    Sorry for the grumpy comment y’all/OP. I’ve had a migraine for days during my vacation week and it’s getting to me.

  • rplnt 19 hours ago

    The completely pointless and oftentime confusing capitalization doesn't help, as usual.

bell-cot 16 hours ago

> “We stopped using lead in our daily lives when we realized how toxic it is, [...]” said corresponding author Alysson Muotri, Ph.D.

I'd say that's a "willfully optimistic" take. https://en.wikipedia.org/wiki/Lead_poisoning#History

  • Jackson__ 10 hours ago

    > In the late 1950s through the 1970s Herbert Needleman and Clair Cameron Patterson did research trying to prove lead's toxicity to humans. In the 1980s Needleman was falsely accused of scientific misconduct by lead industry associates

    > In 1991, together with Claire Ernhart, Scarr was involved as an expert witness on behalf of the lead industry in the lawsuit United States v. Sharon Steel Corp., on the opposite side of Herbert Needleman who was testifying for the U.S. Justice Department owing to his research on the relationship between lead exposure and IQ.[0]

    > When the trial was declared open to the public, Scarr initially refused to come and later when she was persuaded she constantly refused to answer questions. Scarr received money from the lead industry for consulting services which creates a conflict of interest.

    > Scarr retired to Hawaii in 1997, where she learned scuba diving, even obtaining a rescue diver certification. She also traveled "a lot, especially on cruise ships"

    Jesus Christ.

    [0] https://en.wikipedia.org/wiki/Sandra_Scarr

steveBK123 a day ago

Just like Huel!

  • MountDoom 20 hours ago

    I get your joke, but the thesis here isn't that Neanderthals were exposed to more lead. Instead, the claim is that we might have evolved a mutation that protects our brain against lead to some extent.

  • andrewflnr a day ago

    What, did they have a lead contamination issue?

    • ch4s3 20 hours ago

      Any time you collect a bunch of plants, dehydrate them, and pulverize them you’ll end up with a powdered concentration of whatever was in the plants. Since many plants can fix lead and because lead is everywhere you’ll get a little lead. It won’t be much, barely more than 1000x lower than the safe level, but some. Also cadmium probably.

  • zoklet-enjoyer a day ago

    I really wanted to like Huel. I like the idea of their meals, like chilli, but I didn't like it. Their Soylent type drink wasn't good either. Soylent 1.5 was the best.