Spectrometer reveals £20 note secret
A group of scientists based in the West are helping in the worldwide fight against organised crime, drug dealing and terror attacks.
At the Mass Spec Analytical laboratory in Bristol spectrometers are able to detect minute traces of explosives and drugs.
BBC West home affairs correspondent Steve Brodie speaks to Dr Richard Sleeman who makes a surprising discovery about a £20 note from the reporter's wallet.
- From the section Bristol