When heated, teflon frying pans release substances containing fluorine, which can only be broken down very slowly in the environment. This is being reported  by Canadian scientists in today's issue of "Nature". The researchers state that some of these substances accumulate in the ground and in groundwater.

Other substances, on the other hand, may cause a breakdown of ozone in the upper atmosphere layers.

Teflon is part of a group of polymers containing flourine. Apart from frying pans and ovens, these polymers are also in used in internal combustion  engines and in the medical field.

When the researchers heated these polymers, they released a veritable cocktail of chemical fragments. Some of these fragments are already known to contribute to the destruction of the ozone layer in the stratosphere and to the green house effect.

Another chemical fragment found was triflouride acetic acid. This substance has often been detected in rainwater, but its origin has been unclear. This substance is very slow to break down, and very little research has been done on its long term effects on the environment.

Source: Nature, 18.07.01

Research: David A. Ellis, Department of Chemistry, University of Toronto; Jonathan W. Martin, Department of Envrionmental Biology, University of Guelph; Derek C.G. Muir, National Water Research Institute, Environment Canada, Burlington, Kanada; in Nature, Vol.412, No. 6844, July 19. 2001, pp 312- 324