Your post is a little confusing.
Is your a/c charged, or isnt it? If theres no gas in it, then you have nothing to lose. You can just take the fittings loose. If there is still gas in it, you really should have it recovered.
If you get a little on your skin it wont bother you, however you can get frostbite from an excessive amount. R-12 is extrememly harmful to the ozone. By releasing it you could end up with a big fine from the EPA. That is not likely, but under the right circumstances, it is possible.
The EPA rates different refrigerants by their "ODP" (Ozone Depletion Potential) R-12 rates a 3 on their scale. R-22 (used in home air conditioners) rates at a .3.
The higher the number, the higher the depletion potential. My point being, R-12 is very bad for the enviroment. Always recover it whenever possible.
andy