While the reasons for the Fall of the Western Roman Empire are quite complex, a popular theory that has since been disproven suggested that high lead levels in the water supply due to the use of lead pipes was a contributing factor.
What is known is that rain water is slightly acidic due to dissolved carbon dioxide, and carbonate anions can precipitate with calcium cations into a calcium carbonate deposit that decreases how much lead is exposed. While lead levels in the water supply were undoubtedly high, they weren’t necessarily high enough to cause widespread lead toxicity.
The reason why Flint, MI ran into trouble was that their water was too acidic (especially since they forgot to add phosphate buffer for a while) and it dissolved the protective scale and exposed the lead. (Although there are other things wrong with Flint’s water.)
Anyway, the main route of exposure to lead for Roman aristocrats was probably from the lead they sprinkled into their wine to sweeten it.
Lead Poisoning and Rome •