With new analytical techniques, evidence of drug use remains detectable in hair for months. This is the conclusion of the PhD thesis 'Improved forensic hair evidence for drugs of abuse by mass spectrometry' by Wilco Duvivier. He will defend his thesis on 5 July at Wageningen University.
Drug use can be demonstrated by analysing blood or urine, but the traces disappear very quickly. Hair is different. Traces of drug use remain detectable for months, which is useful for forensic and medical testing.
The thesis describes research into improvements in current hair analysis methods for detecting drug use, and entirely new ones. In one new approach, the entire length of a lock of hair is scanned, resulting in a detailed timeline of a person's drug use.
Besides monitoring drug use, in the future these new hair analysis techniques could also be used for detecting the use of prohibited growth stimulants in livestock farming.