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…
Roman Empire's use of lead lowered IQ levels across Europe, study finds
111–120 of 176 posts
Re: Roman Empire's use of lead lowered IQ levels across Europe, study finds
#112I wonder what will happen to current empires from micro- and nano-plastics, PFAS, airpolution, as well as harmful yet popular habits like doomscrolling and games addictions.
Re: Roman Empire's use of lead lowered IQ levels across Europe, study finds
#113Earlier quoted context omitted.
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.
I wouldn't call it nothing. Current regulation requires water supply at the tap to measure 2-3 µg/L is significant.
Re: Roman Empire's use of lead lowered IQ levels across Europe, study finds
#114Earlier quoted context omitted.
Yes it matters. Faster car can run more miles in a day. More IQ can do more work.
Unfortunately for that we have computers so we don't need high IQ to do more work like calculations but higher quality work (which also depends on what kind of work you're doing) and that is oftentimes not primarily related to high IQ (think of creative work)
Re: Roman Empire's use of lead lowered IQ levels across Europe, study finds
#115Earlier quoted context omitted.
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.
Though that goes against Europe hitting the decline earlier than the US which leads in sugars and unhealthy foods.
Re: Roman Empire's use of lead lowered IQ levels across Europe, study finds
#116Earlier quoted context omitted.
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 "…
Re: Roman Empire's use of lead lowered IQ levels across Europe, study finds
#117Rome 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 poss…
Re: Roman Empire's use of lead lowered IQ levels across Europe, study finds
#118I 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…
You obviously would prefer non-lead pipes, but running the water for a period before using flushes out any lead if the pipes are in the house. Like you say in your comment, it's when water sits in a container like a wine vat where leeching has time to accumulate.
Re: Roman Empire's use of lead lowered IQ levels across Europe, study finds
#119> 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.