Rome was the first city on the planet to have an extensive and efficient municipal water system, thanks to the empire's ambitious aqueduct system that's still found throughout Europe. But that infrastructure was also pumping ancient Romans with lead — up to 100 times the amount of lead found in local spring water.
A new study reported in the Proceedings of the National Academy of Sciences confirms that Romans had high levels of lead contaminating their tap water, thanks to the lead pipes that they used to pass the water from aqueducts into the city. Researchers determined the ancient lead levels by taking sediment cores from a Tiber River canal, as well as from the harbour of a nearby port city on the Mediterranean that the canal flows to. Here, they could see a historic record of how waterborne contaminants had accumulated over time.
They found two kinds of lead isotopes in the sediments, one which originated in the mountains and rocks around Rome, and another, highly concentrated isotope which originated elsewhere, possibly from present-day Germany or England. This was likely the lead which was mined in these places and brought back to Italy to build the pipes, and therefore delivered the greater levels to Romans.
It's been theorized for decades that ancient Romans suffered from lead poisoning, which has been blamed for the downfall of the Roman Empire by causing widespread health problems like gout, anemia, and low birth rates, and even psychological issues ranging from mental instability to militant behaviour. But according to the new study, although the levels were high, they were likely not high enough to cause the downfall of the whole civilisation:
"It's marginal. You would start being worried about drinking that water all your life," said Francis Albarède, who led the study at Claude Bernard University in Lyon. "Even though they probably did not get degenerate, as some people say, or even get more violent, lead pollution might have been something to be concerned about."
Since we can't blame lead for the downfall of Rome, we'll have to go back to the original excuse: Christianity. [The Guardian]