The bacteria ‘biosensors’ could let forensic experts know within minutes if someone has traces of mercury, cyanide or arsenic in their bodies, and will be faster and cheaper than current testing methods.

“The biosensing bacteria glow if there is no poison present, but get dimmer if toxic chemicals such as pesticides or inorganic chemicals are found in urine tests,” Environmental Science and Research (ESR) forensic toxicology spokesperson Stuart Dickson says.

Although biosensors are common in medicine, soil and food quality testing, this is believed to be the first time they have been used in forensic toxicology. The test was developed in a joint project between ESR scientists in New Zealand and researchers in Scotland.