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Roman Empire's use of lead lowered IQ levels across Europe, study finds

theguardian.com

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Re: Roman Empire's use of lead lowered IQ levels across Europe, study finds

#91

Post by Anotheroneagain »

somenameforme wrote: post #60
trimethylpurine wrote: post #42

Earlier quoted context omitted.

IQs aren't changing much Isn't IQ a comparative representation of one's standing within their contemporary age group? My understanding is that within a given group the median should be 100. So you won't see it change between groups. This is highly relevant when you're talking about different groups being exposed to different concentrations of lead. As an extreme example to make the point, if people born in 1970 were…

You're right about how IQ is measured with 100 being the average and, generally, 15 points being a standard deviation. But numerous tests also record raw scores and these can be compared between generations. Scandiland and other places with compulsory conscription + IQ testing are the goldmine here. This is what led to the observation of the 'Flynn Effect' - the observation that IQ between generations was increasing,…

The explanation is that IQ measures the cerebellum, and the declining nutrition and increasing brain damage forces people to rely more on the cerebellum, the statistical engine, instead of abstract thinking.

Re: Roman Empire's use of lead lowered IQ levels across Europe, study finds

#92

Post by Anotheroneagain »

thaumasiotes wrote: post #44
trimethylpurine wrote: post #42

Earlier quoted context omitted.

IQs aren't changing much Isn't IQ a comparative representation of one's standing within their contemporary age group? My understanding is that within a given group the median should be 100. So you won't see it change between groups. This is highly relevant when you're talking about different groups being exposed to different concentrations of lead. As an extreme example to make the point, if people born in 1970 were…

You're basically right about the relative nature of IQ scores, but you're wrong about the comparison being drawn. To impute the effect of lead, you look at a bunch of people, measure the amount of lead in their blood, measure their IQs, and see how much of a difference there is between people with a lot of lead and people with less or none. Modern poor people who live in crummy areas where there's still a little bit…

The elites have always been the highest in lead. Slaves etc. had none.

Re: Roman Empire's use of lead lowered IQ levels across Europe, study finds

#93

Post by iSnow »

agumonkey wrote: post #20
cmrdporcupine wrote: post #10

Similarly, arsenical bronze (copper + arsenic) was common before tin started to be used, and I've often wondered how common arsenic poisoning was in the copper age / early bronze age. When we think of the nastiness of industry, it's often industrial 19th century Britain and so on, but some of these villages (often quite remote) back then were full on industrial sites with massive smelting operations and the entire po…

A repair guy taught me recently that up until the 40s cadmium was used as a layer on some metallic devices, then people realized it was toxic. Funny.

Also in pigments. There still has to be lots and lots of old devices, paint in houses, glass ware etc. around that derive their color from Cadmium.

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

Re: Roman Empire's use of lead lowered IQ levels across Europe, study finds

#94

Post by Anotheroneagain »

Rome fell after they stopped using lead.

There is no evidence whatsoever that lead was widely known to be toxic, until a group of conspirationists took over the academia. In fact such a belief couldn't have been widespread. The historical quotes appear to be fabricated.

In fact it's essential. Roman sewers and sanitation quickly flushed it down the drain, by 235 it was in chaos, long distance trade was no longer possible and a thousand years long dark age ensued. The original depletion happened deep in prehistory, the most major event happening around 26kya. Also by ice cores, substantiated by geological changes and mammoth skeletons.

Re: Roman Empire's use of lead lowered IQ levels across Europe, study finds

#95

Post by cma »

nahnahno wrote: post #51
curmudgeon22 wrote: post #3

> On average, lead levels in children’s blood at the peak of the Roman empire could have risen 2.4 micrograms per decilitre, the researchers found, reducing their IQ by 2.5 to 3 points. When taking background lead into account, childhood blood levels may have reached about 3.5 micrograms per decilitre. > A 2021 study by the Centers for Disease Control and Prevention in the US found blood levels in children aged one t…

2.5-3 micrograms per deciliter is nothing. Wouldn’t even come up as elevated by current childhood screening guidelines. I very much doubt 2-3 IQ point difference.

That's the average, so it would be much high the cities in the cities than rurally right?

Re: Roman Empire's use of lead lowered IQ levels across Europe, study finds

#96

Post by bell-cot »

vasco wrote: post #81
peeters wrote: post #46

> Roman Empire’s use of lead lowered IQ levels across Europe, study finds I'm not a fan of this phrasing. None of the findings had anything to do with measuring IQ levels in ancient Europe. They were about measuring historical levels of lead, which they then just plugged into modern models to presume some levels of cognitive effects. A study that was actually able to measure cognitive disparities and correlate them w…

Could also happen that all the advances in hygiene and infrastructure and logistics during the Roman empire had a more positive impact on IQ than the negative effect of lead. Not starving while growing up does wonders for the brain.

Plenty of people starved...just not (in their better centuries) the better-off Romans.

For (presumed) IQ benefits, I'd focus more on the hygiene, and the relatively disease-free drinking water which all those lead pipes & lead-lined aqueducts provided. (Plus the sewers.) There were lots of nasty diseases you could catch by drinking the water in ancient cities. And at scale, "lead lowered IQ" isn't much different to "unable to think well while ill", to "higher mortality makes education a poorer investment".

Re: Roman Empire's use of lead lowered IQ levels across Europe, study finds

#98

Post by SiempreViernes »

Anotheroneagain wrote: post #89
trimethylpurine wrote: post #42

Earlier quoted context omitted.

IQs aren't changing much Isn't IQ a comparative representation of one's standing within their contemporary age group? My understanding is that within a given group the median should be 100. So you won't see it change between groups. This is highly relevant when you're talking about different groups being exposed to different concentrations of lead. As an extreme example to make the point, if people born in 1970 were…

>Then people born in 2000 are exposed to far less lead and are super smart, What do you base this on?

It's clearly meant as a hypothetical example.

Re: Roman Empire's use of lead lowered IQ levels across Europe, study finds

#99

Post by rat87 »

peeters wrote: post #46

> Roman Empire’s use of lead lowered IQ levels across Europe, study finds I'm not a fan of this phrasing. None of the findings had anything to do with measuring IQ levels in ancient Europe. They were about measuring historical levels of lead, which they then just plugged into modern models to presume some levels of cognitive effects. A study that was actually able to measure cognitive disparities and correlate them w…

Would have implies they didn't use lead buy if they had it would have lowered IQs

May have lowered IQs based on extrapolation and modern studies

Might be a better way to put it

Re: Roman Empire's use of lead lowered IQ levels across Europe, study finds

#100

Post by watwut »

SMP-UX wrote: post #66
peeters wrote: post #46

> Roman Empire’s use of lead lowered IQ levels across Europe, study finds I'm not a fan of this phrasing. None of the findings had anything to do with measuring IQ levels in ancient Europe. They were about measuring historical levels of lead, which they then just plugged into modern models to presume some levels of cognitive effects. A study that was actually able to measure cognitive disparities and correlate them w…

This is one of the problems with modern academia. It's hard to extrapolate these things

The guardian article is not academia.
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