TROMSØ, NORWAY—Science Magazine reports that archaeologist Hans Peter Blankholm of the Arctic University of Norway and his colleagues found “unhealthy” levels of toxic metals in the bones of Atlantic cod and harp seals recovered from garbage pits at eight archaeological sites on Norway’s Varanger Peninsula. The sites range in age from 3,800 to 6,300 years old. The analysis revealed that the cod and seal bones both contained high levels of cadmium, lead, and mercury, which can cause organ damage in humans when consumed. The metals are thought to have leached into the water supply as sea levels rose and covered previously dry land. Blankholm and his colleagues said, however, that it is unclear if eating contaminated sea creatures harmed the people who lived in these prehistoric Arctic communities, since they also ate fruit and meat from reindeer and rabbits, and may not have lived long enough to accumulate many pollutants from the otherwise beneficial, high-protein foods from the sea. The next phase of research will analyze human remains recovered from the archaeological sites. To read about prehistoric artifacts emerging from mountain ice patches, go to "Letter from Norway: The Big Melt."