Coal burning may make food supplies less healthy
Coal burning may make food supplies toxic
August 18, 2008
Coal burning is contaminating the Arctic, and may be affecting human health and polar ecosystems, warn scientists writing in the online early edition of the Proceedings of the National Academy of Sciences.
Presenting a record of heavy metal deposition in the Greenland ice sheet from 1772-2003, Joseph R. McConnell and Ross Edwards of the Desert Research Institute in the Nevada System of Higher Education show that contamination from coal-burning was “much higher than expected in the early 20th century, with tenfold increases from preindustrial levels by the early 1900s that were two to five times higher than during recent decades.” The results show that coal-burning is significantly more damaging to the environment than other fossil fuels and suggest pollution may worsen with increased use of coal as an energy source in Asian economies.
“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 lead researcher McConnell “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.”
“Contamination of other sectors may be increasing because of the rapid coal-driven growth of Asian economies,” McConnell and Edwards wrote, noting that heavy metal accumulation in the Arctic food chain, affecting human health. Fish and other marine organisms from the polar region are exported to global food markets. Heavy metal contamination has been associated with birth defects and damage to the central nervous system.
Joseph R. McConnell and Ross Edwards (2008). Coal burning leaves toxic heavy metal legacy in the Arctic. PNAS Early Edition August 18-22.