Fingerprint Test Can Now ID What Person Has Touched

Cutting-edge technology now means fingerprints can reveal much more than just a person's identity, the New York Times reports. A spray developed by US researchers can analyze tiny molecular compounds left behind by the print and tell what materials a person has recently handled—including drugs or explosives. It can also separate one print from many overlapping ones.

The new test can detect as little as a billionth of a gram of material, according to researchers in the journal Science. The technique has great potential for crimefighting, although it was initially developed as a medical tool to quickly detect molecular danger signs. (More fingerprint stories.)