Washington: Testing exhaled breath could be a swift way to tell whether people have been exposed to toxic substances. Scientists have designed a simple, non-invasive hand-held device to test whether one's breath contains traces of any toxic substance that they may have inhaled.

The test has been developed by Andrea M Dietrich, Masoud Agah and their students Heather Vereb and Bassam Alfeeli in civil and environmental engineering, University of Virginia, the journal Environmental Science & Technology reports.

Sampling breath is less invasive than drawing blood, more convenient than taking urine samples and shows promise as an inexpensive method with a fast turnaround time, they state, according to a Virginia statement.

The technology can detect minute amount of substances in the breath and do so quickly -- offering the promise of helping limit human exposure and improve health.