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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

#81

Post by vasco »

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.

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

#82

Post by userbinator »

PeterHolzwarth wrote: post #15

I have no idea if this is true (and honestly can only barely remember the reference, which I read maybe a decade or two ago), but I believe I saw a comment that the interior of lead pipes eventually develop a "calcified" (don't know what else to call it) lining of the lead reacting to water, such that lead stops leeching into the water that passes through the pipes. I believe this came up when reading something about…

I have some late-19th-century books on plumbing that mention the same passivation layer, and so clearly it was known, along with some of the toxic effects of lead, back when it was widely used for plumbing (which I must also mention that the 'plumb' comes from 'plumbum' - Latin for lead.)

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

#83

Post by userbinator »

Mistletoe wrote: post #4
leptoniscool wrote: post #2

I wonder if future historians will see a similar drop after widespread use of plastic

Has plastic been linked to lower IQ?

If anything, the correlation might be the opposite --- look at plasticiser use in East Asian countries, for example.

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

#84

Post by userbinator »

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.

Still widely used in military/aerospace.

https://en.wikipedia.org/wiki/Plating#Cadmium_plating

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

#85

Post by guerrilla »

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…

> models to presume some levels of cognitive effects.

Not "presume", "deduce" or "conclude".

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

#86

Post by timschmidt »

AngryData wrote: post #77
timschmidt wrote: post #17

Earlier quoted context omitted.

It's called mineralization, and happens so long as there are dissolved minerals in the water and PH is correct. Lead contamination happened in Flint, MI because additives to control the water PH were neglected to save cost, and slightly acidic water ate away at the mineralization layer in the pipes and began dissolving the lead again.

I don't know if I would call Flint's water just "slightly" acidic. It was acidic enough for the Flint hospital to complain about their stainless steel sinks rusting, for local automotive plants to dig their own wells because it was destroying parts they were washing, and turned their entire water supply system into swiss cheese that had to be replaced. It might be slightly acidic compared to highly concentrated acids…

Of course you are right, and no offense meant. I grew up in Flint, and have family there to this day. My intention was more to communicate that even small changes in water PH can affect this mineralization layer.

What I rarely see talked about with regard to Flint's water supply is that Detroit was willing to give them water for free, which is documented, and the only explanation that makes sense as to why they weren't taken up on the offer is the state governor's cabinet connections to fracking and a pipeline intended to bring lakewater inland to facilitate fracking. They wanted the taxpayers of Flint to help foot the bill. See: http://banmichiganfracking.org/the-flint-water-connection-to...

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

#87

Post by Ekaros »

PeterHolzwarth wrote: post #15

I have no idea if this is true (and honestly can only barely remember the reference, which I read maybe a decade or two ago), but I believe I saw a comment that the interior of lead pipes eventually develop a "calcified" (don't know what else to call it) lining of the lead reacting to water, such that lead stops leeching into the water that passes through the pipes. I believe this came up when reading something about…

Also when talking about downfall. I think it is also sensible question timeframe when these materials were first used. Was that during raise of empire or after it? As it feels wrong that something that had been used for generations during formation of empire would lead to downfall...

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

#88

Post by baud147258 »

thinkingemote wrote: post #74

Original paper https://www.pnas.org/doi/abs/10.1073/pnas.2419630121 ----- Note this isn't mainly about lead pipes: "most significant... may have been through background air pollution from mining and smelting of silver and lead ores "

> smelting of silver and lead ores

The smelting of silver and lead is detectable via ice cores, I remember seeing a graph showing the height of Roman silver production was only matched in the 18th century https://en.wikipedia.org/wiki/Roman_economy#/media/File:Worl...

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

#89

Post by Anotheroneagain »

trimethylpurine wrote: post #42
thaumasiotes wrote: post #23

Earlier quoted context omitted.

> reducing their IQ by 2.5 to 3 points I seem to recall reading an article that observed that every time we do a study of the effect of lead exposure on IQ, it gets larger. IQs aren't changing much, but lead exposure is going down, and so we keep imputing the same IQ gaps to ever-smaller quantities of lead.

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?

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

#90

Post by Anotheroneagain »

lifeisstillgood wrote: post #69

> A 2021 study by the Centers for Disease Control and Prevention in the US found blood levels in children aged one to five years fell from 15.2 to 0.83 micrograms per decilitre between the late 1970s and 2016 as leaded fuels were banned. So if my generation had lead levels 3-4 X higher than Roman kids, does this explain the “Exams are getting easier” meme - that exams are staying the same, but kids really are getting…

Exams are getting easier, because children are getting dumber, and wouldn't pass if they stayed the same.
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