Environment's stuck with nonstick coatings.

Environment's stuck with nonstick coatings.The family of nonstick materials that includes Teflon can degrade into pollutants that persist in the environment, new research suggests.  Known as fluoropolymers, these Teflon Coatings get their tough and slippery traits from fluorinefluorine (fl`ərēn, –rĭn), gaseous chemical element; symbol F; at. no. 9; at. wt. 18.998403; m.p. −219.6&degC;; b.p. −188.14&degC;; density 1.  atoms strongly bonded to the materials' carbon backbones. Manufacturers use the materials in products ranging from frying pans and other kitchen items to engines and electrical insulation.  Scott A. Mabury of the University of TorontoResearch at the University of Toronto has been responsible for the world's first electronic heart pacemaker, artificial larynx, single-lung transplant, nerve transplant, artificial pancreas, chemical laser, G-suit, the first practical electron microscope, the first cloning of T-cells,  and his colleagues heated a variety of fluoropolymers to 360 [degrees] C and 500 [degrees] C. In both cases, a version of nuclear magnetic resonancenuclear magnetic resonance: see magnetic resonance. nuclear magnetic resonance (NMR)Selective absorption of very high-frequency radio waves by certain atomic nuclei subjected to a strong stationary magnetic field.  analysis tuned to detect fluorine showed that the materials broke down into several undesirable products. One of these, called trifluoroacetate (TFATFA Teach For AmericaTFA Thyroid Foundation of AmericaTFA Trifluoroacetic AcidTFA Trans Fatty AcidTFA Two Factor Authentication (computer security authentication)TFA Texas Forensic AssociationTFA Total Fatty Acids ), is toxic to plants, and there's no evidence that it degrades in the environment. Environmental concentrations are low now but could eventually build to troublesome levels, say the researchers.  Other breakdown products included long-lasting fluorine- and chlorine-rich carboxylic acids, which might have negative health and environmental effects because animal tissues absorb them, Mabury's group reports in the July 19 NATURE. Moreover, Mabury says the team was surprised to find ozone-depleting chlorofluorocarbonschlorofluorocarbons (klōr'əflr`əkär'bənz, klôr'–) (CFCs), organic compounds that contain carbon, chlorine, and fluorine atoms.  (CFCs) and greenhouse gases known as fluorocarbons coming from the heated materials.  The researchers discovered the chemical cocktail while trying to solve a riddle, says Mabury. PTFE Coated Several years ago, scientists realized that gases known as hydrochlorofluorocarbonshydrochlorofluorocarbons: see under chlorofluorocarbons.  and hydrofluorocarbonshydrofluorocarbons: see under chlorofluorocarbons. , which have replaced ozone-destroying CFCs in many products, break down in the atmosphere to form TFA. However, the amount of TFA measured in the environment is much higher than this process could supply.  Using environmental models depicting TFA's diffusion into Toronto rainwater, Mabury's group found evidence that the widespread heating of fluoropolymers could produce the missing TFA. Among the sources for such heat are engines and open burning of household trash, Mabury notes.  This is "a plausible explanation for the observed amounts of [TFA] in rainwater around and downwind of urban areas," comments Tim Wallington, an atmospheric chemist with the Ford Motor Co. in Dearborn, Mich. Even so, he says, the benefits of such coatings currently outweigh their risks.  Mabury agrees. "I'm not getting rid of my frying pans," he says.  Still, since TFA sticks around for so long, researchers ought to keep an eye onto watch.- Shak.See also: Eye  it, adds Thomas M. Cahill of Trent University in Peterborough, Ontario. "In order to do that, we need to know how the stuff is getting into the environment," he says. On that score, he says, Mabury and his colleagues have "plugged a fairly significant hole [in our knowledge base]."  "It fills a nice little gap, but it's not a big gap that it fills," comments Hartmut Frank of the University of BayreuthFounded in 1975, the University of Bayreuth is one of the youngest universities in Germany. It's a medium size university with 9,500 students and 186 professorships. (2004/2005) External linkUniversity of Bayreuth   in Germany. Significant sources of TFA in the environment, particularly in the oceans, are still missing, he says.COPYRIGHT 2001 Science Service, Inc.No portion of this article can be reproduced without the express written permission from the copyright holder.Copyright 2001, Gale Group. All rights reserved. Gale Group is a Thomson Corporation Company.