Explanation: A rare bit of OC from me!
The Roman Empire’s organizational and material technology was incredible, so much that it managed to harness the resources of Europe more efficiently than any combination of countries would for over 1500 years after its height. Quite impressive! Metallurgy, in particular, was pursued with great enthusiasm - resulting in a large amount of lead, used in various applications. Silver ore, silver being the main component of Roman currency, was a great contributor to the lead supplies of the Empire, as much of the accessible silver (galena) had to be separated from lead.
However, the Romans understood the danger of lead, and the often-suggested transmission route, that of water pipes, Romans recognized and counteracted pretty effectively!
… but recent research suggests a more insidious transmission route - the air itself. Ice cores dated to the period of the height of Roman industry show extremely elevated levels of lead in the air - to the degree that it may have decreased the average IQ (useless for measuring individuals, but sometimes useful in measuring general drops in demographic ability) by ~2% across all of Europe at the time. Comparable to the height of leaded gas in the 20th century AD. 😬
As the Romans had no conception of lead lingering in the air long after the smoke had dissipated, they were unaware of - and thus helpless against - this threat, even if they were inclined to counter it.
Wow, interesting! Thanks for sharing.
Do you have a link to the paper?
I find it insane if indeed they managed to increase lead levels on such a scale at that time in history. I knew they were well organised and an industrial power house, but increasing lead levels more than we did with leaded gasoline is … impressive albeit in a sad way.
Do you have a link to the paper?
Sure do! Cutting edge stuff - published just in 2025!
https://www.pnas.org/doi/10.1073/pnas.2419630121
The detrimental effects of modern lead exposure on human health are widely recognized. Evidence from the Roman era indicates substantial lead exposure that potentially impacted human health more than 2,000 y ago. The most significant exposure for the rural, nonelite population may have been to background air pollution from silver mining and smelting that underpinned the Roman economy. Using detailed records of Roman-era lead pollution measured in Arctic ice cores and atmospheric modeling, we show that lead emissions from these activities elevated air concentrations throughout Europe. Based on modern epidemiological studies, this air pollution enhanced childhood blood lead levels (BLLs) by about 2.4 µg/dl leading to widespread cognitive decline including an estimated 2.5-to-3 point reduction in intelligence quotient.
I find it insane if indeed they managed to increase lead levels on such a scale at that time in history. I knew they were well organised and an industrial power house, but increasing lead levels more than we did with leaded gasoline is … impressive albeit in a sad way.
Immensely sad. They knew about the poison, but didn’t understand it was all around them.
Europe wouldn’t reach the industrial output of the Roman Empire until ~1600 AD - ~1800 AD - and by that time, silver smelting methods were more advanced and less lead-heavy.
You’ll never convince me we’re not seeing a repeat of this history due to the Baby Boomers’ long term exposure to leaded gasoline
