GUATEMALA: Something deadly was lurking beneath many Maya settlements—mercury. A geochemical survey of soil from 10 Maya sites across Central America revealed that 7 contain dangerous levels of the toxic element. This was likely caused by widespread use of cinnabar, which contains mercury, during the Classic period (A.D. 150–900). The bright red mineral was common in paint and decorations and was used in rituals. Mercury that seeped through soil into the water table would clearly have been hazardous to the health of those who lived at the sites.