Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Lead poisoning causes more death, IQ loss than thought: study

medicalxpress.com

Post reply on HN
Print view View original

201–210 of 479 posts

Re: Lead poisoning causes more death, IQ loss than thought: study

#201

Post by londons_explore »

gpt5 wrote: post #47
djmips wrote: post #22

Earlier quoted context omitted.

It is my understanding that the common filter pitchers don't filter out lead.

That's not correct. It depends on the water filter. A common Brita filter doesn't filter lead. But the referenced filter (Epic) does. There are other filters that can do that, the most popular is ZeroWater, which you can check their datasheet https://www.zerowater.eu/wp-content/uploads/ZeroWater-NSF-ce...

Be dubious of those claims. Lead can be in hundreds of chemical compounds. I very much doubt they have tested the filter against all of them.

Only reverse osmosis will do a decent job of removing lead, and even that won't be perfect.

Re: Lead poisoning causes more death, IQ loss than thought: study

#202

Post by toast0 »

weaksauce wrote: post #58
aidenn0 wrote: post #25

Earlier quoted context omitted.

I had a stop valve that went bad and I wanted to replace it with a ball-valve because I prefer quarter-turn valves for shutoff valves. No ball-valves at the hardware store were lead free.

just a fair warning that you should close that quarter-turn valve very gradually when there is running water if you ever find a non-leaded version... water hammer can and will burst the weakest of your pipes.

If we're warning about valves, be sure that your gate valves are fully open (or fully closed), otherwise the gate will erode and may erode to the point where it can no longer close.

Re: Lead poisoning causes more death, IQ loss than thought: study

#203

Post by 0xcde4c3db »

8f2ab37a-ed6c wrote: post #165

So is IQ a "largely pseudoscientific swindle" to quote a popular article from a few years ago, or is it not? Because if the consensus is that it doesn't matter, then why bother using it as a metric here?

I think it depends on the scope of what's being addressed as "IQ". As far as I know, there are some fairly robust methods and results around IQ, but it's usually hard to make the leap from those to a sales pitch for any particular product/service/policy/program in a similarly robust way. So any given invocation of IQ in the wider world has a high likelihood of being somewhere between scientifically sketchy and outright nonsensical. It's reminiscent of quantum mechanics and epigenetics in that sense.

Re: Lead poisoning causes more death, IQ loss than thought: study

#204

Post by Natsu »

JumpCrisscross wrote: post #194
Natsu wrote: post #144

Earlier quoted context omitted.

One problem with a lot of the studies is that the studies have a lot of confoundeing and estimates of lead's harm seem to be rising even as exposure decreases, which should make people stop and think more. But this doesn't come up that much because it is obviously bad for you, and there's generally no good reason not to avoid exposure and not many people care about precisely how bad it is for you. But it's weird that…

> estimates of lead's harm seem to be rising even as exposure decreases, which should make people stop and think more Is the effect size or confidence rising? The latter makes sense. We're moving from a population systematically exposed to lead (no control) to one with lead-free kids for a change.

Effect size, at least for harm to IQ:

What is the effect of 1 μg of lead on IQ?

Good studies from the different research eras can be used to illustrate how lead effect sizes have changed over time.

Landrigan et al. (1975) represents the Early Era. In this study, there were 46 children in the high lead group and 78 in the control group. Their respective BLLs were 48.3 and 26.9 in 1972 and 40.5 and 26.5 in 1973, and they were 8.3 and 9.3 years old, respectively. So we have a gigantic 14 μg/dL gap between these groups. The high lead group had an average IQ of 88.02 versus 92.88 for the low lead group, or a 4.86 point IQ gap, and thus a per μg effect of 0.35 IQ points.

Baghurst et al. (1992) represents the Middle Era. In this study, there were 494 children who had IQ results, and they were divided into quartiles by BLLs. The mean concentrations of blood at assessment age were 6.6 μg/dL for the lowest quartile, 10.1 for the second, 13.7 for the third, and 20.0 for the final one. Their IQs were 109.6, 107.7, 102.7, and 98.7, respectively. Going from the lowest to the highest lead exposure quartiles, we have a BLL difference of 13.4 μg/dL and an IQ difference of 10.9 points. Going quartile to quartile, the effect of 1 μg of lead was 0.54 IQ points, 1.39 IQ points, and then 0.63 IQ points, with the aggregate (1 - 4) being 0.81 IQ points.

Kim, Yu & Lee (2010) represents the the Modern Era. In this study, there were 302 children who were median-split by BLLs. The high BLL group had a mean BLL of 3.74 and the low BLL group had a mean of 1.92 with IQs of 106.4 and 110, respectively. These differences of 1.82 μg/dL and 3.60 IQ points mean that the per μg/dL IQ drop was 1.98 points.

Re: Lead poisoning causes more death, IQ loss than thought: study

#205

Post by mrguyorama »

crote wrote: post #154
xboxnolifes wrote: post #45

Earlier quoted context omitted.

In the past it was common knowledge not to. It's of much more uncertainty as house plumbing has changed.

That's because it is primarily a historical artifact[0]. Most modern plumbing heats water on-demand, which pretty much entirely avoids the risk of storage tank contamination or Legionella. [0]: https://www.youtube.com/watch?v=HfHgUu_8KgA

>Most modern plumbing heats water on-demand

Where is this the case? These kind of things are extremely locational and here in the US it seems like 45 gallon hot water tanks are still the norm. We had a fad with "on demand" hot water heating but everyone gave up on it when the "it saves you money" part didn't work so well.

Re: Lead poisoning causes more death, IQ loss than thought: study

#206

Post by rngname22 »

hedora wrote: post #27
rngname22 wrote: post #12

epic water filter + nalgene 32 oz hdpe bottle is a great, lightweight filtered drinking water on-demand system filter pitchers are easy to use and a good safe guard against poor plumbing if you haven't had your home water tested

HDPE Nalgene bottles probably leach PFAS: https://www.reddit.com/r/Nalgene/comments/wqdgbi/are_nalgene... Glass or stainless steel would be a better choice (especially for storage).

My old bottle with this same filter was glass, but it was very heavy and it also ended up shattering when I was climbing a mountain and lost my balance and had to toss it onto a nearby ledge. And the filter itself filters a lot of pfas and other microcontaminants.

"That's why we've taken a layered approach, incorporating a variety of high-performance filter media into one powerful filter. Crafted and rigorously tested in the United States, this multi-layered filter is engineered to effectively target both tap water pollutants such as chlorine, microplastics, lead, PFAS, and more, as well as outdoor water contaminants like bacteria, viruses, and microbial cysts like cryptosporidium and giardia."

And the lid and straw itself is also made of plastic. Life is hard and something is better than nothing.

Re: Lead poisoning causes more death, IQ loss than thought: study

#207

Post by placesalt »

trashface wrote: post #125
hedora wrote: post #6

I'd like to point out that, although it is illegal to put lead in water supply lines in the US, there is a loophole that allows it in hot water lines. As a result, for certain fittings, most big-box hardware stores only sell the leaded variants, and label them "hot water heater supply line" or something similar.

There is also an exception for leaded gas in small/private jets ("AVGas") so its used in some of those formulations.

It took ages, but that is finally being phased out

> On February 23, 2022, the FAA joined aviation and petroleum industry stakeholders to announce a comprehensive public-private partnership to transition to lead-free aviation fuels for piston-engine aircraft by the end of 2030.

https://www.faa.gov/about/initiatives/avgas

Re: Lead poisoning causes more death, IQ loss than thought: study

#208

Post by mrguyorama »

CodeWriter23 wrote: post #174
98codes wrote: post #155

Earlier quoted context omitted.

Wow -- how often for how long were/are they going?

I don’t know how much their exposure was but I’d estimate they are closer to the skinny edge of the bell curve.

Maybe they had especially bad practices, like never washed their hands, exclusively eats finger food after picking through their spent bullets and licks their fingers?

Re: Lead poisoning causes more death, IQ loss than thought: study

#209

Post by seventytwo »

jmount wrote: post #190

And lead is still allowed in aviation fuel. The planes (only piston?) are spraying it all over you every day.

Is this actually true? I think that’s changed. Also - how much of a problem is it? What kind of lead exposure do I receive from a small airplane flying over me one day? What does this risk compare to, say, smoking? Or not wearing my seat belt?

Simply stating that a bad thing exists is not enough.

Re: Lead poisoning causes more death, IQ loss than thought: study

#210

Post by tjohns »

jmount wrote: post #190

And lead is still allowed in aviation fuel. The planes (only piston?) are spraying it all over you every day.

It's being actively phased out. The replacement for 100LL was literally just approved by the FAA a year ago, after decades of work.

Many of the bay area airports have already started offering 94UL unleaded fuel, and the others across the country are likely to follow suit shortly.

Post reply on HN