Why did the Romans suddenly have a lower IQ?

Lead pollution during the Roman period could have reduced IQ scores by up to three points, a new study suggests.

The study, published in the Proceedings of the National Academy of Sciences (PNAS), looked at the effects of lead pollution on human health during the height of the Roman Empire, which lasted about 200 years, beginning around 27 BC.

According to Euronews on January 8, researchers examined the records of three ice core samples collected from the Arctic to determine the level of lead contamination with high accuracy.

Restoration of a Roman mosaic in Italy

"We took physical measurements of lead pollution, used atmospheric modeling to determine what lead concentrations were like in Europe 2,000 years ago, and then used these modern epidemiological correlations to link air pollution to blood lead concentrations in children," said Professor Joe McConnell, who led the study.

According to the study, more than 500 kilotons of lead were released into the atmosphere during the Roman period due to mining activities. Scientists combined these measurements with modern research on lead levels and cognitive decline to determine IQ loss, and concluded that the level of lead exposure during the Roman period was enough to reduce IQ by 2.5 to 3 points, with those near the mines being affected more.

Scientists say the study aims to increase understanding of the severity of lead poisoning in the context of air pollution. The team also considered only inhaled lead in the air, not lead from soil, plants and water.

“A 2.5 to 3 point drop in IQ may not sound like much, but on a population-wide scale, it's significant,” said McConnell.

What did children 2,000 years ago draw on walls?

In addition to air pollution, people are exposed to lead in other ways, through utensils, paints, and cosmetics. Today, lead exposure is known to be especially harmful to young children and women of childbearing age. The World Health Organization (WHO) says that even low levels of lead exposure can affect brain development.

Source: https://thanhnien.vn/vi-sao-nguoi-la-ma-bat-ngo-giam-iq-185250109085656541.htm