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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

#191

Post by ska »

javert wrote: post #77
lotsofpulp wrote: post #70

Earlier quoted context omitted.

The societal risks are the same with additional worse effects for non participants with alcohol and they have been known for a long time. If society is OK with those risks, then I cannot see cannabis being an unacceptable risk in 50 years. Can throw in refined sugar too.

> The societal risks are the same and additional worse ones with alcohol I don't think this is correct, personally. (I'm pretty sure you'll find studies arguing for both sides, so we can only go on personal wisdom.)

> I'm pretty sure you'll find studies arguing for both sides, so we can only go on personal wisdom.

Without opinion on the relative damage of both, I'll note that considering this a logical statement is really flawed.

You can pretty much always find "studies arguing for both sides" on an issue, but that doesn't mean much in and of itself.

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

#192

Post by staticassertion »

arcticbull wrote: post #147
legitster wrote: post #136

Earlier quoted context omitted.

The study in the linked article found that lead reduced the IQ of exposed Americans 3-6 IQ points. A New Zealand study found that persistent cannabis users had a 6-8 point decline, even if they had given up cannabis : https://www.pnas.org/doi/abs/10.1073/pnas.1206820109 Here's a meta review that found a 2 IQ point drop across a wider range of usage types: https://www.cambridge.org/core/journals/psychological-medici..…

That's not actually what the study found. Further, cessation of cannabis use did not fully restore neuropsychological functioning *among adolescent-onset cannabis users*. They did not find a 6-8 point decline for folks who gave up cannabis if they started later in life. In fact they found no decline in IQ whatsoever for folks who started later in life - both when using it and after stopping. In contrast, within-perso…

Sorry, I took a look at the study and I couldn't tell - what is an adolescent? Like, 10-18? 14-25? I know what the word means, but for a scientific study I assume there's a specific range they're referring to.

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

#193

Post by micromacrofoot »

ryan93 wrote: post #138
micromacrofoot wrote: post #73

Earlier quoted context omitted.

> But then there's been a huge rise in crime Is this actually true? I've seen a lot of people saying this politically but haven't seen a lot of data to back it up. From what I've seen there's been a slight bump, which isn't too surprising given the state of everything... but it's still massively dwarfed by the decrease in the 90s and 00s For example https://www.bbc.com/news/57581270

https://www.pewresearch.org/fact-tank/2021/10/27/what-we-kno...

Thanks! this supports the fact that it's still lower than before the 90s decline, and possibly pandemic related. I guess we'll find out over the next few years.

> Despite rising sharply in 2020, the U.S. murder rate remains below the levels of the early 1990s.

> Americans remain far less likely to die from murder than from other causes, including from suicide and drug overdose.

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

#194

Post by pfranz »

xhkkffbf wrote: post #49
micromacrofoot wrote: post #3

Earlier quoted context omitted.

From what I've read the removal of lead from gasoline is partially a factor in the sudden reduction of crime during the latter half of the 20th century, but it's not enough to explain the entire trend... which seems to be a preponderance of factors.

But then there's been a huge rise in crime. The murder rate in some cities is dramatically higher than just a few years ago. But it's not like the gas suddenly became leaded again. This makes me think that we just can't be too certain about these things.

From what I've seen there has been a recent rise in the murder rate. In some places it was at historical highs--but the cities are also much, much larger now. When looking at per-capita data its still historically low.

You're right in that there doesn't seem to be a definitive cause, but quite a few things have changed since Covid started and we're not sure what changes are permanent.

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

#195

Post by giobox »

coding123 wrote: post #172
wutbrodo wrote: post #90

Earlier quoted context omitted.

Can we? Everything I understand about the public tells me otherwise.

It does seem weird to me that about 5-10% of a grocery store is bottles of alcohol.

Fluids consume large amounts of shelf space by volume regardless of what fluid it is, not much we can do about this, so a large amount of shelf space does not mean a large percentage of the store's total items, in theory. By percentage of total items, it's likely very small for most supermarkets.

See also the large amount of shelf space typically required to stock bottled water and soft drinks.

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

#196

Post by bnralt »

KennyBlanken wrote: post #127
WhompingWindows wrote: post #103

Earlier quoted context omitted.

Marijuana needs to be reclassified off of Schedule I Status in the USA, so it can be more thoroughly studied. Schedule I category shouldn't include recreational drugs like marijuana, which has no overdose possibility and has limited withdrawal side-effects. This wrong classification, going back to ignorant viewpoints of the early-mid 1900's, has heavily limited our scientific understanding of marijuana's effects on h…

> This wrong classification, going back to ignorant viewpoints of the early-mid 1900's It "goes back" to Nixon needing a tool to criminalize the anti-war and racial justice movement. https://www.cnn.com/2016/03/23/politics/john-ehrlichman-rich... By the time Nixon came out with that policy, multiple commissions around the world had concluded that pot was largely harmless and should be decriminalized. People in his ow…

I've tried doing deep dives into drug criminalization a few times before, and I've never been able to find a simplistic explanation for it. Keep in mind, this is something that every country in the world went forward with around the same time, even when they were adversaries who couldn't agree on much else. This was also something that nations often did on their own. A lot of these movements start much earlier than people think; look at Mexico's moves against cannabis in the late 1800's early 1900's. Or even the Gin Craze of the 1700's for a precursor.

There seem to be a few threads I've found that are worth pursuing:

1. The general increase in state power in various domains of life .

2. The decline of traditional communities and move toward urbanization creating a disconnected group of people that worried the upper classes.

3. The tendency of geopolitics to follow social trends/fads.

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

#197

Post by pedrosorio »

giobox wrote: post #188
dylan604 wrote: post #173

Earlier quoted context omitted.

> It does no harm to a user, to third parties, nor to society, Except it opens doors in people's minds which allows them to think differently for themselves. This results in them behaving less like sheeple. Why would that ever be scary for society?

My experience is it opens the door to not thinking much at all, but your mileage may vary. Is there anything more "sheeple" like than a bunch of stoned people sitting around not motivated to do much? Sure, not all mj users may experience it this way, but a lot do! I certainly wouldn't be arguing it opens the door to a bunch of usefully profound thinkers in society.

Parent's quote refers to the psychedelic DMT, not to mj.

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

#198

Post by staticassertion »

mrits wrote: post #175
antattack wrote: post #160

Earlier quoted context omitted.

Smoking (anything) is bad for your lungs, throat too.

Not a huge problem when we die from diabetes or heart disease first.

Something being bad for your lungs is presumably going to be very bad for your heart.

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

#199

Post by throwaway0a5e »

lern_too_spel wrote: post #176
throwaway0a5e wrote: post #157

Earlier quoted context omitted.

That is an incredibly naive way of looking at it. The way it usually goes is "everyone is +5, except the village that shares the watershed with the mine" On anything but the shortest timeline things like like wealth, health and productivity are fungible at the societal level. If the net cumulative effect of the externalities wasn't smaller than the benefits of the progress then the progress wouldn't happen because mo…

Not only is it not naive, but avoiding these scenarios woth market regulation is one of the main purposes of modern government. Hence, vaccination policies and CFC regulation. Libertarians like to believe that negative externalities and other market failures don't exist, that the invisible hand is always benevolent, but examples abound for those who do not follow a religion that forbids them from noticing.

>Not only is it not naive, but avoiding these scenarios woth market regulation is one of the main purposes of modern government. Hence, vaccination policies and CFC regulation. Libertarians like to believe that negative externalities and other market failures don't exist, that the invisible hand is always benevolent, but examples abound for those who do not follow a religion that forbids them from noticing.

It's still naive, or maybe obtuse. Repeating the "negative externality" buzzword doesn't give you a blank check to peddle your preferred ideology (government intervention/regulation) while crapping on the other team.

Without regulation we get lithium batteries and a couple dozen poisoned watersheds.

With regulation we get slightly more expensive batteries and fewer poisoned watersheds.

Regardless of how you or I or anyone else feels about regulation it's somewhere between farcical and deceitful to pretend that the economic activity in both of those situations doesn't help more than it hurts. If it didn't work this way progress would grind to a halt because the increased material wealth of having the batteries would be more than cancelled out by the problems that poisoned watersheds create, to run with the existing example.

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

#200

Post by teknopaul »

Independent of the effect of lead on intelligence isn't it impossible to reduce the IQ of half the population because IQ is a comparative calculation across that population. Ie as intelligence goes down the definition of 100 IQ points changes?

https://en.m.wikipedia.org/wiki/Intelligence_quotient

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