Ancient Greece, widely recognized for contributions to democracy and philosophy, is now associated with the earliest recorded instance of environmental lead pollution. Researchers from Heidelberg University examined sediment cores collected from mainland Greece and the Aegean Sea, revealing evidence of lead contamination dating back 5,200 years. This discovery predates the previously known oldest lead pollution, identified in a Serbian peat bog, by 1,200 years. In antiquity, lead was emitted into the atmosphere as a byproduct of smelting ores to extract copper and silver. The toxic metal then condensed into dust and settled into the soil. The study, published in Communications Earth and Environment, identified the earliest signs of lead pollution near Thasos, an island in northeastern Greece historically known for silver mining and metalwork. Archaeological evidence suggests that lead pollution remained localized and minimal throughout the Bronze Age, Classical period, and Hellenistic period. The Classical period is notable for Athenian democracy and philosophers like Socrates and Plato, while the Hellenistic period marked the peak of Greek cultural influence across the Mediterranean.

A significant and abrupt increase in lead emissions was detected approximately 2,150 years ago, coinciding with the Roman conquest of Greece in 146 B.C. The integration of Greece into the Roman Empire transformed the region’s economic and societal structures. Increased demand for silver coin production led to intensified smelting, releasing more lead into the environment. Additionally, the Romans utilized lead extensively in construction, such as pipes, and in tableware. This study offers a more localized perspective on historical lead pollution, supplementing previous research that analyzed Greenland ice cores. Environmental experts emphasize that this discovery enhances the understanding of ancient industrial activities and their long-term environmental impacts.