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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

#21

Post by CyberDildonics »

luxuryballs wrote: post #18
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…

[flagged]

Lots of people across the world don't have fluoride in their water, you could compare populations right now.

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

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

#23

Post by thaumasiotes »

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…

> 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.

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

#24

Post by SteveNuts »

luxuryballs wrote: post #18
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…

[flagged]

Why specifically call out fluoride?

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

#25

Post by WorkerBee28474 »

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 haven't read it, but the book History of Toxicology and Environmental Health [0] would say that pipes were not a problem. Preparing food and wine in lead containers could have been a problem, but it wasn't until centuries after the Roman Empire "fell" that doctors even described the symptoms of lead poisoning.

And to throw in another quote from a scholarly source, "Water from the river Anio, which fed two of Rome's principal aqueducts, the Aqua Anio Vetus and Aqua Anio Novus, was particularly hard and conveyed high levels of dissolved calcium carbonate. Indeed, Frontinus complains in his treatise on the aqueducts of Rome, that "the accumulation of deposit, which sometimes hardens into a crust, contracts the channel of the water" (CXXII.1)." [1]

[0] https://www.sciencedirect.com/book/9780128153390/toxicology-...

[1] https://penelope.uchicago.edu/encyclopaedia_romana/wine/lead...

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

#26

Post by ahazred8ta »

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…

"Did arsenic poisoning make gods limp?" Apparently going lame was an occupational hazard. https://www.abc.net.au/science/articles/2015/03/31/4206279.h...

It was common from 4000 BC to 2000 BC. Ötzi the iceman lived near a copper-arsenic forge site. https://en.wikipedia.org/wiki/Arsenical_bronze#Arsenical_bro...

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

#27

Post by __MatrixMan__ »

sebmellen wrote: post #14
__MatrixMan__ wrote: post #9

Earlier quoted context omitted.

Maybe, but given that "plastics" are a broad category I'd expect that IQ would me a poor proxy for some of their effects. BPA for instance, is a xenoestrogen. I'm not sure what metric to watch for it, but it's probably not IQ.

Anogenital distance is likely the preferred measure. > Males with a short AGD (lower than the median around 52 mm (2 in)) have seven times the chance of being sub-fertile as those with a longer AGD. > Swan et al. report that the levels of phthalates associated with significant AGD reductions are found in approximately one-quarter of Americans tested by the Centers for Disease Control and Prevention (CDC) for phthalat…

I was imagining something a bit more impactful (and easy to find in the data), because as far as that one goes, it's not clear why anyone should know or care.

Maybe high school graduation rate (an inverse proxy to indicate bullying)?

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

#28

Post by lolinder »

SteveNuts wrote: post #24
luxuryballs wrote: post #18

Earlier quoted context omitted.

[flagged]

Why specifically call out fluoride?

It's a bit of a thing with a particular political persuasion in the US right now (RFK Jr has made his anti-fluoride position a big part of his deal for his future role as Secretary of Health and Human Services), and there was a report in the news recently that some see as backing up the claims against fluoride:

https://www.latimes.com/science/story/2025-01-06/what-a-new-...

It's not as conclusive a study as some people might claim, though:

> For starters, 52 of the 74 studies were judged by the report authors to have a “high risk of bias.” That undermines the validity and reliability of their results.

> Another issue is that most of the studies considered fluoride exposures far above the target level for the U.S. ... Only seven of the studies assessed children whose water contained less than 1.5 mg/L of fluoride. When they were considered on their own, there was no relationship between fluoride exposure and IQ.

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

#30

Post by cmrdporcupine »

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.

I mean, I can do better (worse). Up until .. the 60s? 70s? They used to literally spray lead-arsenate on apple orchards as a pesticide.

Incredibly effective one, too.

Just that unfortunate thing of poisoning the top soil forever.

A lot of those old apple orchards have had other things done with them since. Which is kind of scary.

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

"US EPA banned use of lead arsenate on food crops in 1988."

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