SEVILLE, SPAIN—According to a statement released by the University of Seville, a team of researchers including Steven D. Emslie of the University of North Carolina Wilmington examined the remains of 370 individuals recovered from 50 tombs at 23 archaeological sites spanning a period of 5,000 years in Spain and Portugal. The researchers determined that people who lived at the beginning of the Copper Age, between 2900 and 2600 B.C., were exposed to high levels of mercury. Contact with mercury is thought to have come through the use of cinnabar—a mercury sulfide mineral that yields a brilliant red powder when pulverized. Throughout the Copper Age, paint made with cinnabar powder was used to decorate figurines, stelas, the bodies of the dead, and megalithic chambers in Portugal and Andalusia. Today, the normal level of mercury in hair is considered to be one or two parts per million. During the Copper Age, however, levels of 400 parts per million have been detected in the bones of some individuals. These people may have inhaled the powder while working with it, or may have even ritually inhaled or ingested it. To read about a rare form of liquid cinnabar found at Teotihuacan, go to "Mythological Mercury Pool," one of ARCHAEOLOGY's Top 10 Discoveries of 2015.