Ancient Lead Emissions Polluted Arctic
Researchers have discovered lead emissions from ancient Roman and Greek smelters buried in British peat and Swedish lake sediments (SN: 3/26/94, p.198). But a new study shows that ancient airborne pollutants traveled even farther and contaminated the lower atmosphere of the lower Arctic.
"This...marks the oldest large-scale hemispheric pollution ever reported," Sungmin Hong of Domaine University in Grenoble, France, and his colleagues assert in the Sept. 23 SCIENCE.
The team analyzed cores drilled by the European Greenland Ice Core Project in central Greenland. Lead production increased during a period of Roman cultural expansion 2,500 to 1,700 years ago. Lead concentrations reached a high of about 2 picograms per gram (pg/g) of ice during the 800-year span. This is nearly four times the amount found in ice dating to before people began working lead.
At its peak, lead production in ancient Rome totaled about 80,000 metric tons per year, rivaling the output during the Industrial Revolution, the Hong group calculates. …