Amid concern about the potential toxic effects of the fluorochemicals used in nonstick cookware, water-repellent clothing, and other consumer products, manufacturers are using new versions of these chemicals that may be safer. That's the topic of the cover story in the current issue of Chemical & Engineering News (C&EN), ACS' weekly newsmagazine.
C&EN Senior Editor Stephen K. Ritter cites indications that long-chain compounds like perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) can cause developmental problems, liver toxicity, and cancer in animals. Uncertainty exists over their health effects in people. Nevertheless, chemical companies are working with the U.S. Environmental Protection Agency (EPA) to phase out PFOS and are in the process of phasing out PFOA. The companies are replacing these chemicals with shorter chain fluorochemicals that perform just as well but appear to be safer.
Although these new ingredients are considered sound replacements, they may only be a temporary fix, pending development of a new generation of less toxic substitutes. After being surprised by the unexpected environmental persistence of PFOA and PFOS, EPA is taking extra caution with the replacements to avoid a similar problem in the future.
via Alternative chemicals ease safety concerns about nonstick, repellent coatings.
I stopped using Teflon coated pans years ago when I gave up fluoride toothpaste. I don't know if fluorine gas could be released from heating Teflon ( Fluorine gas kills ) but it seems clear that the pans do emit polymer fumes.
In chemistry, polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer of tetrafluoroethylene which finds numerous applications. PTFE is most well known by the DuPont brand name Teflon.
PTFE is a fluorocarbon solid, as it is a high molecular weight compound consisting wholly of carbon and fluorine. Neither water and water-containing substances nor oil and oil-containing substances are wet by PTFE, as fluorocarbons demonstrate mitigated London dispersion forces due to the high electronegativity of fluorine. PTFE has one of the lowest coefficients of friction against any solid.
PTFE is used as a non-stick coating for pans and other cookware. It is very non-reactive, partly because of the strength of carbon–fluorine bonds, and so it is often used in containers and pipework for reactive and corrosive chemicals. Where used as a lubricant, PTFE reduces friction, wear and energy consumption of machinery.
In January 2006, DuPont, the only company that manufactures PFOA in the US, agreed to eliminate releases of the chemical from its manufacturing plants by 2015, but did not commit to completely phasing out its use of the chemical. In the emulsion polymerization of PTFE, 3M subsidiary Dyneon has a replacement emulsifer despite DuPont stating PFOA is an "essential processing aid". As of August 2008, the EPA's position was that it "has no information that routine use of household or other products using fluoropolymers, such as non-stick cookware or all weather clothing, poses a concern."
The C8 Science Panel is the result of a court settlement, with three epidemiologists investigating if PFOA exposure in the community surrounding DuPont's Teflon producing Washington Works facility likely results in health effects. - wikipedia
Your non-stick pans can kill your birds. I think non-stick pans killed some finches we had when I was a kid, but we just thought they were unhealthy.
Polytetraflouethylene, (PTFE), was discovered in 1941. It is found in the fumes of non stick coatings. The danger of PTFE is that the fumes are odorless and colorless and it is not clear how long it lingers in the air. PTFE is found in most non stick cook and bakeware. Non stick coatings are made by many maufacturers, under many different names.
The first case of human suffering from polytetrafluoroethylene problems was reported in 1951. In humans, polytetrafluoroethylene produces flu like symptoms and is called "polymer fume fever," and is rarely fatal. For birds, contact with PTFE fumes can often prove fatal, occurring within as little as 5 minutes of exposure to the fumes.
Non stick begins to emit fumes as soon as it is heated. It was thought at one time that PTFE became dangerous only when over heated. It is now reported that temperatures as low as 285 degrees F can release PTFE fumes which can prove dangerous and fatal to our birds. In the case of cookware, a pan does not have to be burnt to emit PTFE fumes, or to become dangerous to our birds. If we are lucky enough that our birds are not effected immediately, the fumes emitted into the air linger indeterminably and they do circulate. If you have multiple birds residing in your home, the fumes may not effect all the birds, effect them all at the same time. The toxic fumes become airborne and travel on air currants in the house. The air currant containing the toxic fumes can by-pass one bird and come in contact with another; the fumes acting similarly to the way smoke would when it becomes air borne.
One well known manufacturor of polytetrafluoroethylene claims that its coating remains intact at 500 degrees F and that it takes only 5 minutes for one of their pans coated in non stick surfacing to reach a 736 degrees F. It takes only 3 minutes and 20 seconds for competitive brands of non stick coating to reach the same temperature. Researchers at the U of Missouri documented the death of 1,000 chicken chicks at 396 degrees F, exposed to the "offgas"; gases emitted by nonstick coated heat lamps. The boiling point of water is 212 degrees F at sea level, lower than the point where PTFE fumes begin to emit into the air. Foods that are fried should be fried at 350 to 360 degrees F. - qp-society.com
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