Roman Empire: How lead reduction reduced the IQ of the population

Roman Empire: How lead reduction reduced the IQ of the population

New research results show worrying effects of lead pollution 2000 years ago: Scientists have discovered that the air during the "Pax Romana", a time of stability and expansion of the Roman Empire, was massively stressed with lead. These findings come from ice drilling nuclei, which were analyzed during a study under the direction of Joe McConnell from Desert Research Institute (DRI). As Kleine Zeitung reported, the lead concentration increased through the intensive silver mining, which was of central importance for the Roman economy.

The connection between lead pollution and intelligence

The study shows that the lead concentration in the air drastically increases during the flowering period of the Roman empire. This pollution led to the average IQ of people in the Roman Empire reduced by 2.5 to 3 points. Scientists demonstrated that children under the age of five had an average of 3.4 micrograms per deciliter, which not only harmed them in terms of health, but also impaired their cognitive skills. According to Science.de , the enormous lead concentration could also be made to high mortality during the Antoninian plague, which raged between 165 and 180 AD and killed up to ten percent of the population.

The data obtained by modern scientific methods illustrate that over 500,000 tons of lead came into the atmosphere during the Pax Romana. This not only affected locally, but across Europe and had catastrophic consequences for the health of the people of the time. "An IQ reduction by two to three points may seem low to us, but this is enormous in the overall picture of the European population," says Nathan Chellman from Dri.