Coal's Toxic Legacy Revealed in Greenland Ice Core

Proving that Big Coal's nefarious influence knows no bounds, a new study published in the Proceedings of the National Academy of Sciences has shown that pollution from coal burning has contaminated the Arctic for the last 100 years. Measurements taken from an ice core in Greenland, dating from 1772 to 2003, showed that the levels of the toxic heavy metals cadmium, thallium and lead were much higher than predicted -- which may have impacted human health in this and neighboring regions.

Surprisingly, however, the authors, Joe McConnell and Ross Edwards of Reno's Desert Research Institute, found that pollution levels were higher at the beginning of the previous century -- and not during the 1960s and 70s, which most scientists had expected.

Coal pollution levels at their worst during 1900s
The reasoning behind this is that countries in Europe and North America reached the peak of industrial activity during those two decades -- right when the landmark Clean Air and Clean Water Acts were being passed, in 1963 and 1972, respectively. McConnell explained that pollution levels in southern Greenland were higher during the early 1900s because coal-burning technologies were dirtier than they are now; indeed, pollutant levels were 2-5 times higher then than they are today.

Rapid growth of Asian economies could worsen pollutant levels in the Arctic
While pollution levels have decreased since their peaks at the beginning of the 20th century, the authors are concerned that the high levels of emissions being produced by the coal-fueled Chinese and Indian economies could pose a threat to the health of Arctic ecosystems (for a visual, check out my previous post on China's air pollution).

Thallium, cadmium, lead and other heavy metals carried through the atmosphere and deposited in these regions tend to concentrate in higher trophic levels, putting at risk marine organisms like seals and whales and the humans that feed on them (think the effects DDT and PBDEs have had on peregrine falcons and other birds).

For a good overview of the study's results and its significance, check out this video interview of DRI researcher Joe McConnell.

(By Jeremy Elton Jacquot, TreeHugger, 19/08/2008)