Scrutinized chemicals linger in atmosphere

Don’t look up now, but new research indicates that industrial chemicals called fluorotelomer alcohols, or FTOHs, may remain suspended in the air for several weeks on average. Their longevity in the atmosphere suggests that they may widely disperse before degrading into durable environmental contaminants that have been found far from industrialized areas.

FTOHs are ingredients in many consumer products, including paints, polishes, adhesives, waxes, and stain-repellent coatings. Gradually, the chemicals escape into the air. Some scientists presume that FTOHs and related alcohols break down into extremely durable, so-called perfluorinated chemicals, which are widespread in the environment and have recently been found to accumulate in and harm animals (SN: 8/30/03, p. 142: Available to subscribers at Nonstick but not nontoxic).

To determine whether FTOHs have the wherewithal to spread far and wide, Scott Mabury of the University of Toronto and his colleagues at the university and at Ford Motor Company in Dearborn, Mich., simulated natural chemical interactions that would tend to degrade FTOHs in the atmosphere. The breakdown rates the team measured for three different FTOHs suggest that the humanmade substances remain intact and airborne for about 20 days, the scientists report in the Sept. 1 Environmental Science and Technology.

Mabury and his colleagues estimate that FTOHs could therefore travel about 7,000 kilometers before breaking down. Further study is needed to determine whether the breakdown products include hardy perfluorinated contaminants, they say.

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