Airport Security Liquid Diagnostic

I work at the airport, and having to go through security every day you start to notice things. As you probably know liquids in amounts over 3fl oz have been banned. This means that if somebody has a bottle of shampoo they have to throw it away, and if it's a water bottle they have to empty it into a bucket at security. They should spend some of those tax dollars on equipping airports with machines which would detect dangerous chemicals in liquids. Instead of handing over a beverage a passenger could just pour a capful of the drink into the top of this machine, and if no chemical was detected they could pass. I don't know a lot about chemical detection/mass spectrometry but a machine like that should be simple enough (?) to make. Warnings would go off for petroleum products, nitro glycerin, acids, & other known chemical agents. The 'spent' drink samples would empty into a resovior once tested.