Roman Lead Pollution During Pax Romana Caused 2-3 IQ Point Decline

Jan 7, 2025, 05:23 AM

A recent study published in the Proceedings of the National Academy of Sciences reveals that lead pollution during the Roman Empire caused a significant cognitive decline across Europe. Researchers from the Desert Research Institute analyzed Arctic and Greenland ice cores to trace atmospheric lead levels between 500 BCE and 600 CE. The findings indicate that silver mining and smelting activities during the Pax Romana, a 200-year period of relative peace and prosperity, released over 500 kilotons of lead into the atmosphere. This resulted in an estimated 2.5-3 point drop in IQ levels across the population, with childhood blood lead levels increasing by approximately 2.4 micrograms per deciliter. The study highlights the earliest known example of widespread industrial pollution and its impact on human health. The research also suggests that lead exposure may have contributed to the decline of the Roman Empire, though other factors such as the Antonine Plague, economic instability, and plagues played a role. Lead exposure, even at low levels, is linked to cognitive impairments, reduced academic success, and other health issues, underscoring the long-term consequences of industrial activities.