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Lead exposure in last century shrunk IQ scores of half of Americans: study

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Re: Lead exposure in last century shrunk IQ scores of half of Americans: study

#441

Post by jounker »

hadlock wrote: post #289
jccooper wrote: post #258

For context, leaded gasoline phase-out began in 1973, based on the 1970 Clean Air Act. It was largely gone in the US by the 80s but not officially eliminated (except for General Aviation) until 1996. Other countries continued to use leaded gasoline, largely in Africa and the Middle East; the UN started an effort in 2002 to eliminate it in those places still using it. In July 2021, the last stocks of leaded gasoline (…

Yeah in the US I recall in 1991 or 92 the pumps had "UNLEADED" in great big letters running up the side of them. My dad's '77 chevy had a gas gauge near the center console that said "UNLEADED FUEL ONLY". There's been another push to get rid of leaded gas in aviation but studies show that it's virtually undetectable in the environment.

Given that you can smell the jet fuel downwind from an airport, I’d be greatly suspicious of those studies. They don’t seem to pass the smell test.

Re: Lead exposure in last century shrunk IQ scores of half of Americans: study

#442

Post by jounker »

dionidium wrote: post #294
veltas wrote: post #6

Didn't we have a previous study debunking this research on statistical grounds?

What has never made sense to me is that the IQ effects aren't equally visible across income/class groups, but we know there are millions of wealthy people living in old housing in Boston and NYC and Providence and so on. Lead levels in those houses must be just as high, right? But those kids aren't experiencing the same IQ effects. Surely this suggests that something else is a bigger factor?

If you have money, and it’s your house then you get the old paint stripped when you repaint. If you are buying a home, and there is lead paint, then you negotiate down on the price to compensate for removal.

Landlords of shitty apartments or houses just slap a new coat of the cheapest possible paint over the old.

Re: Lead exposure in last century shrunk IQ scores of half of Americans: study

#443

Post by ransom1538 »

tyjen wrote: post #309
breakyerself wrote: post #248

Black children had an adjusted 0.73 to 1.41 µg/dL more blood Pb (p https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7084658/

Learned about this phenomenon when considering buying a home built prior to 1978. The highest blood lead levels are seen in children living in denser population areas at or below poverty thresholds. Homes in these largely urban, low-income areas are disproportionately built before 1978 and subject inhabiting children to a significantly higher lead exposure risk. In 2014, it was estimated that 90 percent of all DC hom…

Buying a home pre-1978 is a mess. Every contractor asks "what year is the home". If you state something before 1978 - they wont open a wall, touch old tiles, do roof work, etc. Contractors immediately offer one of their friends to do asbestos removal or lead work. I had water leak in a 1967 home. Just to throw away plaster walls cost a fortune: "hazardous material". It looked like a sci-fi movie people in full outfits, full plastic wrapped rooms, negative pressure systems, air locks. My home insurance wouldn't pay - then dropped me that year.

Re: Lead exposure in last century shrunk IQ scores of half of Americans: study

#444

Post by hindsightbias »

downrightmike wrote: post #365

Small airports have more smaller prop planes, fun fact, they almost exclusively use leaded gas because it gives them more power. So if you live near one, you're getting a dusting of lead everyday. Like this one in the middle of $500k+ homes suburbs: https://www.google.com/maps/place/Chandler+Municipal+Airport...

When land developers finally get their hands on Reid-Hillview, you can be 100% sure of one thing: they won’t offer or be required to do any lead mitigation putting up all those condos.

Re: Lead exposure in last century shrunk IQ scores of half of Americans: study

#445

Post by phlipski »

This message feed reminds me of the (excellent) book "Cradle to Cradle". It's about sustainable design/manufacturing and one of the lines that has stuck with me since I read it years ago was (summarizing here), "In the US we regulate how much poison is acceptable per person rather than just outright eliminating the poison!"

Re: Lead exposure in last century shrunk IQ scores of half of Americans: study

#446

Post by sojournerc »

S201 wrote: post #362
istjohn wrote: post #331

Earlier quoted context omitted.

And we still use leaded fuel in aviation. [1] 1. https://www.faa.gov/about/initiatives/avgas

GA pilot here. This is true and most of us don't like using leaded gas either. It's nasty stuff that leads to increased wear on our engines, is more expensive, and is increasingly used as justification for closing airports. Plus we're exposed to it when fueling our planes. However, it's worth mentioning that recently the first unleaded avgas, G100UL, was approved by the FAA. We're trying to move away from 100LL (lead…

I agree with you except the increased wear. Lead is a lubricant and is/was an additive introduced to intentionally decrease wear.

That is largely why the FAA is reluctant to certify older high-compression engines for non-leaded fuel. AFAIK

Re: Lead exposure in last century shrunk IQ scores of half of Americans: study

#447

Post by kortilla »

nicolas_t wrote: post #337

I was recently horrified to learn that the baby glass bottle I had been using with my baby had lead paint on it. https://tamararubin.com/2021/12/sailor-themed-glass-nuk-baby... Apparently, it's considered to be acceptable by current standards. Despite the fact that babies will obviously touch the bottle (and the paint) and then put their hands in their mouth. I bought glass bottles because I wanted to avoid plastic t…

Being afraid of things in acceptable doses is just as ignorant and unhelpful as not being afraid at all.

Re: Lead exposure in last century shrunk IQ scores of half of Americans: study

#448

Post by marcosdumay »

jounker wrote: post #441
hadlock wrote: post #289

Earlier quoted context omitted.

Yeah in the US I recall in 1991 or 92 the pumps had "UNLEADED" in great big letters running up the side of them. My dad's '77 chevy had a gas gauge near the center console that said "UNLEADED FUEL ONLY". There's been another push to get rid of leaded gas in aviation but studies show that it's virtually undetectable in the environment.

Given that you can smell the jet fuel downwind from an airport, I’d be greatly suspicious of those studies. They don’t seem to pass the smell test.

On one hand, benzene goes much farther than any lead-containing organic compound, and the dispersal is exponential, so it's really much farther.

On the other hand, the thing is literally being dispersed from the high-up, so who knows. It is really a strange result, as one should expect detectable differences even if not large enough to matter. Is water carrying it away?

Re: Lead exposure in last century shrunk IQ scores of half of Americans: study

#449

Post by coryrc »

TigeriusKirk wrote: post #433
downrightmike wrote: post #365

Small airports have more smaller prop planes, fun fact, they almost exclusively use leaded gas because it gives them more power. So if you live near one, you're getting a dusting of lead everyday. Like this one in the middle of $500k+ homes suburbs: https://www.google.com/maps/place/Chandler+Municipal+Airport...

The good news is the FAA is working to eliminate lead from general aviation fuel by 2030. https://www.faa.gov/newsroom/faa-industry-chart-path-elimina...

They could just approved the alternatives today, if the APA wasn't lobbying because it saves them a little money to continue poisoning us.

Re: Lead exposure in last century shrunk IQ scores of half of Americans: study

#450

Post by sojournerc »

jounker wrote: post #441
hadlock wrote: post #289

Earlier quoted context omitted.

Yeah in the US I recall in 1991 or 92 the pumps had "UNLEADED" in great big letters running up the side of them. My dad's '77 chevy had a gas gauge near the center console that said "UNLEADED FUEL ONLY". There's been another push to get rid of leaded gas in aviation but studies show that it's virtually undetectable in the environment.

Given that you can smell the jet fuel downwind from an airport, I’d be greatly suspicious of those studies. They don’t seem to pass the smell test.

Leaded gas used in general aviation is not jet fuel. Slightly higher octane than "car" fuel, but definitely not jet fuel which is basically kerosene. I could be wrong, but I don't think you could smell the difference between leaded and non-leaded fuel in exhaust.
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