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

medicalxpress.com

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

#451

Post by Gibbon1 »

ClumsyPilot wrote: post #243
londons_explore wrote: post #183

Earlier quoted context omitted.

I think op may be referring to 'barrier pipe', which is a plastic -copper-plastic sandwich, which is designed to keep out pollutants which can diffuse through the plastic - eg. Diesel oil. If you don't use it for underground water pipes in cities, you'll normally get complaints from homeowners about 'chemical smelling' water, particularly first thing in the morning when water has been sitting stationary in pipes all…

oh dear i forgot that plastics are permeable to petrochemicals lile paper is to water

There is a test for plastics where they weigh a block of plastic then soak it in water and weigh it again. For some plastics the gain in weight can be a few percent.

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

#452

Post by mkoubaa »

harry8 wrote: post #364
mkoubaa wrote: post #252

Earlier quoted context omitted.

Most IQ skeptics think IQ correlates with intelligence. The argument is generally over how good a proxy it is for intelligence and what conclusions can and can't be drawn from statements about IQ

False. Low IQ correlates with lack of intelligence. Average and above means nothing. --IQ skeptic

That's still a loose correlation, but I do appreciate the correction

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

#453

Post by aidenn0 »

tbrownaw wrote: post #335
swayvil wrote: post #319

Earlier quoted context omitted.

If all of the IQs in a county went down we might investigate that. There's one. If we were looking for smart people for a role in whatever. There's another. If we were rating schools. There's a third. Gee, my imagination is feeling so stretched.

> If all of the IQs in a county went down we might investigate that. There's one. The average is always by definition exactly 100, neither higher nor lower. Also, this data already exists. The folks who make standardized tests collect it to use for translating raw results to standardized scores. > If we were looking for smart people for a role in whatever. There's another. This is illegal. There are ways to get the s…

> > If all of the IQs in a county went down we might investigate that. There's one.

> The average is always by definition exactly 100, neither higher nor lower.

The average for the population that the test is normalized is exactly 100. GP was suggesting that if the averaged dropped in a single locality (specifically county, but I'm generalizing), which is completely possible.

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

#454

Post by aidenn0 »

weaksauce wrote: post #440
kube-system wrote: post #257

Earlier quoted context omitted.

I use quarter turn ball valves everywhere and slam the crap out of them. If a pipe bursts from that, it needs to be fixed, and I’d rather it happen while I’m there slamming valves around than when I’m not home. But it has never happened.

you don't have embedded copper water lines in concrete slabs I assume? sure a little drywall damage is nothing but having to jackhammer that up is a bigger ask.

I've seen people just abandon those lines in favor of running pex through the walls rather than fix them.

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

#455

Post by reducesuffering »

kortilla wrote: post #399
Gigachad wrote: post #367

Earlier quoted context omitted.

Had a friend from Texas move near me in Australia and they have just been exhausted trying to keep up because they aren't used to walking. Walking here is the fastest and most convenient way to get around. By the time you get your car out and find parking, you could have already been there on foot. You'll observe that the rate of obesity is extremely low in the walkable areas which I really think is heavily because t…

The rate of obesity is low because of survivorship bias, nothing more, nothing less. For obese and/or disabled people, living in New York is an absolute nightmare if you can’t afford public transit. Despite loving the city amenities, culture, nightlife, one of my family members had to give up and leave NYC because he couldn’t afford cabs everywhere and hated showing up to events late and sweat-soaked otherwise.

> The rate of obesity is low because of survivorship bias, nothing more, nothing less

You think the rate of obesity is not at all affected by the amount of walking?

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

#456

Post by p3rls »

ComputerGuru wrote: post #382
p3rls wrote: post #226

Earlier quoted context omitted.

I am a plumber and sprinkler tech (nyc) and literally have never seen a broken pipe that could reliably be traced to water hammer damage. Really would only be concerned if you are building fire safety systems. Now those sudden GPMs need some support.

I had a problem just this past summer hooking up a pressure washer to a hose outlet. After two hours of constant on-off cycling, had the pipe leading to the hose bib burst. You could hear the water hammer quite clearly (and violently!) after I repaired it, so I went back and added a hammer arrestor.

To me what I hear: your pipes weren't supported and your pressure is too high if it can be described as violent. I can hear my old office's script telling me to sell you a PRV or two.

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

#457

Post by amluto »

WalterBright wrote: post #439
amluto wrote: post #433

Earlier quoted context omitted.

Stainless steel is just fine in a copper system if it’s not electrically connected to the copper. Even if it is, you are unlikely to have problems unless the wetted area of the stainless steel is comparable to or larger than the copper, in which case you may accelerate corrosion of the copper. You won’t have the problems you would have with galvanized steel. Copper ions leached out of a copper pipe will react with zi…

Stainless in (or near) contact with copper with moisture between them forms a battery, which will corrode them. Metals in a plumbing (i.e. wet) system need to be either isolated from each other or be galvanically compatible. This applies to roofing, too. Nail the flashing down with galvanically compatible nails, or you'll find the flashing all comes loose after a couple years.

> Stainless in (or near) contact with copper with moisture between them forms a battery, which will corrode them.

Not really?

A battery has two paired half reactions. Something gets oxidized, something gets reduced, and electrons flow through the conductive bits.

So if you have some metallic zinc, and you have some copper ions, and you have some metallic copper, and you have electrical contact, zinc will be oxidized, copper ions will be reduced and plate into the copper, and current will flow. Once the zinc is gone, if you had galvanized steel to start with, the iron will oxidize.

Now try stainless steel. The half-reaction involving the stainless steel, hmm, doesn’t involve iron — the iron is physically separated from the electrolyte by the passive layer. Chromium? Barely - a tiny bit oxidizes and then it stops. We’re left with 2H+ + 2e- -> H2. Which can happen without the stainless steel too, but with more available surface area, it’s faster.

So a lot of stainless steel will accelerate the corrosion of a small amount of copper. But the reverse has little effect.

There is apparently a real concern the with H2: some grades of stainless steel are apparently rather susceptible to hydrogen embrittlement.

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

#458

Post by arcticbull »

nate_meurer wrote: post #448
arcticbull wrote: post #167

Earlier quoted context omitted.

There's not really any issue with asbestos as long as you leave it alone and don't mess with it. It doesn't need to be torn out unless you're renovating. > "THE BEST THING TO DO WITH ASBESTOS MATERIAL IN GOOD CONDITION IS TO LEAVE IT ALONE!" [1] [1] https://www.cpsc.gov/safety-education/safety-guides/home/asb...

Kinda hard to do when your ceiling is covered in delicate popcorn asbestos that showers down on you every time it gets touched. This is very common.

If they're crumbling or damaged they should be abated, but if they're in good condition they don't pose a risk.

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

#459

Post by nate_meurer »

arcticbull wrote: post #458
nate_meurer wrote: post #448

Earlier quoted context omitted.

Kinda hard to do when your ceiling is covered in delicate popcorn asbestos that showers down on you every time it gets touched. This is very common.

If they're crumbling or damaged they should be abated, but if they're in good condition they don't pose a risk.

There is no such thing as a popcorn ceiling that doesn't crumble every time you so much as change a lighting fixture.

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

#460

Post by datavirtue »

sokoloff wrote: post #302
datavirtue wrote: post #294

Earlier quoted context omitted.

I recently fell in love with copper pipes. So many advantages, so easy to work with. Quick and nearly fool-proof. I tried introducing some stainless fixtures and did not have a good time with it. I'm not a pro by any means but I do all of my own plumbing and gas work in my house. Haven't had one issue out of iron gas pipe or copper water lines. I was actually planning a pex install/replacement, and I have worked with…

People often go to Pex because it's way cheaper than copper. I use copper because the rest of my house supply is copper, soldering pipe is a skill that I have and enjoy using, there's a slight anti-microbial action from copper, and I trust it to last longer than I have years left around. I sure don't do it because it's cheaper, though.

Straight new install of PEX might be cheaper but I can reuse copper fittings and they cost nearly nothing. Same with the runs of pipe...I can reuse copper without losing length. Just easier to deal with for maintenance.
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