Common chemicals morphing into potential toxins in Arctic

Alcohols last up to 20 days in atmosphere.

Compounds used to protect carpets and fabrics may be travelling to remote regions of the planet and undergoing chemical reactions before building up in the food chain, says a new study from the University of Toronto.

Until now, scientists had no idea why the persistent chemicals – perfluorinated carboxylic acids (PFCAs) – were present in remote areas such as the Canadian Arctic, says U of T postdoctoral research fellow Jonathan Martin, a study co-author in the lab of chemistry professor Scott Mabury. "We've shown that fluorotelomer alcohols – chemicals used to prevent stains on textiles and in the electronics manufacturing industry – appear to last for up to 20 days in the atmosphere and are capable of delivering PFCAs to remote environments," he says. The study was published in the June 15 issue of Environmental Science and Technology.

Chemists at U of T, the Ford Motor Company and the University of Copenhagen used a smog chamber to simulate how the alcohols degrade in the atmosphere and discovered a previously unknown reaction that produced PFCAs. Martin says the team also found the compounds in polar bear liver tissue samples. Other studies are examining exposure levels in humans living in the far north.

"It does appear to be an issue that's going to affect Arctic food webs and Arctic people who depend on them. We don't know toxicologically how much of these chemicals an animal can withstand before it might start to cause problems," says Martin, noting that previous studies have suggested that a form of PFCAs in a mother's blood may pose developmental risks.

The study was funded by Natural Sciences and Engineering Research Council of Canada and the Danish Research Council.

23-jun-2004