Your halitosis contains countless organic molecules, from acetone - the chemical ingredient in nail polish remover - and volatile sulfur compounds to ammonia and carbon monoxide in smokers. If you abuse illegal drugs, additional compounds can be found there, and technology now exists to detect them in bad breath.
Toxicologists at the Karolinska Institutet in Sweden have announced a new method of drug testing that resembles a tried and true alcohol detector - the breathalyzer.
They published their findings in a recent issue of the Journal of Analytical Toxicology.
The team experimented with a breath-analysis system that collected exhaled air and tested it for the presence of drugs. Participants, who had all been admitted to medical care for amphetamine use, were asked to breath into a specially built mask for ten minutes.
Their breath - presumably bad breath - passed through a filter, where scientists inspected its contents using liquid chromatography and mass spectrometry, which are very sensitive methods of analyzing material for its constituent elements.
The team found that they were able to detect drugs on breath in concentrations as low as 0.2 trillionths of a gram per minute, even after the physical effects of amphetamines had disappeared.
Current urine and blood analysis technology cannot detect drugs in nearly such small amounts. The team said this breath-testing system may one day be used alongside breathalyzers in testing individuals for drugs.
A similar proposal, published in the journal Analytical Chemistry, recently unveiled another innovation in breath inspection technology - the detection of exhaled acetone, whose presence in high enough amounts indicates the onset of type 1 diabetes.
It's little wonder that the participants in the Swedish study had bad breath. The use of amphetamines and methamphetamines can cause a number of unpleasant oral side effects. These include dry mouth and gingivitis, each of which is an agent of halitosis. When the mouth is infected or unmoistened, anaerobic bacteria rapidly multiply and emit sulfuric molecules that smell strongly, even in tiny amounts.
However, amphetamines can do worse to the mouth than that. Heavy users of the drug often develop what is informally called "meth mouth," which the American Dental Association says can cause teeth to develop severe tartar, rot and fall out. This condition contributes to breath that would haunt even the most hard-nosed toxicologist.
Besides avoiding illegal substances, the best ways to prevent bad breath are to brush, floss and consider using specialty breath freshening products.