Tear gasses as a class are called Lachrrymators. As seen here: http://en.wikipedia.org/wiki/Tear_gas they act against enzymes, but I can also tell you that they release very acidic materials such as Hydrochloric Acid. So, I suggest that you take care with the camera and film so as to prevent corrosion and other problems. The release of these corrosive components only take place in the presence of water, so keep the camera, lens and film dry.

I have made one particularly potent variety of tear gas in the lab at one time or another so I am well aware of the properties. I have also worked with many Lachrymators. They are no fun!

PE