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Lead Exposures in Ancient Rome
A paper published in the Jan. 21 issue of Proceedings of the National Academy of Sciences (PNAS) presents estimates of atmospheric lead pollution and blood-lead levels in ancient Rome. Basing their estimates on evidence from Arctic ice and atmospheric modeling, researchers examined the period between 500 BCE and 600 CE. They identified an increase in lead pollution around 15 BCE, and levels stayed high through 180 CE, the end of the Pax Romana. Information from media reports about the research appears below.
From “Ancient Romans Breathed in Enough Lead to Lower Their IQs, Study Finds. Did That Toxin Contribute to the Empire’s Fall?”:
“During the roughly 200-year stretch of the Pax Romana, the Romans were extracting and smelting a lot of silver to make coins. These processes are known to emit large amounts of lead into the atmosphere.”
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RESOURCES
Proceedings of the National Academy of Sciences: “Pan-European Atmospheric Lead Pollution, Enhanced Blood Lead Levels, and Cognitive Decline from Roman-Era Mining and Smelting” (January 2025).
Smithsonian Magazine: “Ancient Romans Breathed in Enough Lead to Lower Their IQs, Study Finds. Did That Toxin Contribute to the Empire’s Fall?” (January 2025).