"Greenland lead pollution tracked plagues, wars and empires" Topic

An 1100 BCE to 800 CE record of estimated lead emissions based on continuous, subannually resolved, and precisely dated measurements of lead pollution in deep Greenland ice and atmospheric modeling shows that European emissions closely varied with historical events, including imperial expansion, wars, and major plagues. Emissions rose coeval with Phoenician expansion and accelerated during expanded Carthaginian and Roman lead–silver mining primarily in the Iberian Peninsula. Emissions fluctuated synchronously with wars and political instability, particularly during the Roman Republic, reaching a sustained maximum during the Roman Empire before plunging in the second century coincident with the Antonine plague, and remaining low for >500 years. Bullion in silver coinage declined in parallel, reflecting the importance of lead–silver mining in ancient economies.

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It was all the leaded gas used to run their chariots.

Dan

Makes sense. High level mining and smelting production, especially away from the Italian peninsula, is predicated on political and social stability. Wars make for an increased need for metals but may make it more difficult to access the materials.