@freakazoid, I don't think so. They have explosive residue detectors, and they might have drug-sniffing dogs wandering around, but I don't think they religiously screen every piece of luggage, or even a majority of luggage, for drugs... unless there's enough of it to raise suspicion after an x-ray. International travel is probably a different matter, since they'd want to screen for illegal smuggling of plants and animals (to prevent drug smuggling, to prevent import/export duty avoidance, and to prevent accidental insect, bacteria, and virus import/export), but I think even there they still rely mostly on hand searches.
Does even the DEA have scanners for drugs? Is there any agency or place where bio+electronic scanners are used in lieu of drug k-9 units for detecting drugs? I've read about various drug detecting technologies over the years but I've never read of them being commercialized and mass produced.