Greenland ice core reveals history of pollution in ...( New research reported this week in t...)

New research, reported this week in the online early edition of the Proceedings of the National Academy of Sciences, finds that coal burning, primarily in North America and Europe, contaminated the Arctic and potentially affected human health and ecosystems in and around Earth's polar regions.

The study, titled "Coal Burning Leaves Toxic Heavy Metal Legacy in the Arctic," was conducted by the Desert Research Institute (DRI), Reno, Nev. and partially funded by the National Science Foundation.

Detailed measurements from a Greenland ice core showed pollutants from burning coal--the toxic heavy metals cadmium, thallium and lead--were much higher than expected. The catch, however, was the pollutants weren't higher at the times when researchers expected peaks.

"Conventional wisdom held that toxic heavy metals were higher in the 1960s and '70s, the peak of industrial activity in Europe and North America and certainly before implementation of Clean Air Act controls in the early 1970s," said Joe McConnell, lead researcher and director of DRI's Ultra-Trace Chemistry Laboratory.

"But it turns out pollution in southern Greenland was higher 100 years ago when North American and European economies ran on coal, before the advent of cleaner, more efficient coal burning technologies and the switch to oil and gas-based economies," McConnell said.

In fact, the research showed pollutants were two to five times higher at the beginning of the previous century than today. Pollution levels in the early 1900s also represented a 10-fold increase from preindustrial levels.

Continuous, monthly and annually averaged pollution records taken from the Greenland ice core dating from 1772-2003 produced the results. And although data showed heavy-metal pollution in the North Atlantic sector of the Arctic is substantially lower today than a century ago, McConnell and his research partner, Ross Edwards, an associate r
'/>"/>