Research Help

Crazzyass

I'm doing an environmental science project. I've located a tobacco barn, and I'm taking air, water, and soil samples around the barns and away from them to see the difference in composition. I have pretty solid tests for the water and soil samples, and I've laid out particulate strips for the air, but I would like to do a qualitative analysis of some air samples. Do you have any ideas for relatively cheap (<$100) qualitative tests for air samples?