Originally Posted by Chef2337
.... Since the aresol in cooking sprays is what is bad for you and destroys your pans leaving that sticky residue. ...
The cooking sprays that come in a can (all of them that I am familar with) are not pure oil - they are a blend of oils and include added lecithin - which gives the spray it's non-stick quality ... BUT can cause the pan to develop a sticky residue if too much is used and ESPECIALLY if sprayed on non-stick cookware. The problem is that the lecithin is a chemical cousin of non-stick coatings - it forms a chemical bond which causes it to form an incomplete polymer (like not properly seasoning cast iron to fully polymerize the oil - leaving a sticky residue) - it has nothing to do with the propellant used as far as I know.
Now, I will admit that I have not read the labels of every iteration of every brand of cooking spray on the market. But the ones I have read seem to all agree on the "do not use on non-stick cookware" idea.
I can't use canned non-stick sprays indoors because I have asthma - it has nothing to do with the propellant - it has to do with the amount of fine particulate matter (mist) in the air. I have no problems if I go outdoors to spray it as long as the wind is at my back. I have a similar problem using a spritzer bottle to spray pure oil - just not as much of a problem because the mist is not as fine and does not linger in the air as long.
Personally - I find that if I pour a little oil into my pot/pan and wipe it around with a folded up paper towel I achieve the same results - I wind up with a small amount of oil coating the surface without it being aerosolized - and thus no over-spray that I have to wipe up off of the stovetop or a counter top.
Now - back to momerlyn's post ... I had never seen that either, but in some ways it might make sense. The heat will break down the surface tension in the small spray particles - allowing them to spread out and provide a better more uniform coverage of the pan surface.