Hair, science and crims

By Anna Sandiford 28/02/2010


Analysing hair for criminal casework purposes has had some new developments recently, as reported in Forensic Science International. For your delectation and delight, and as the journal has a log in, I have decided to share some of the papers that deal with day-to-day issues to which we can all relate:

In Sweden, if someone is convicted of either drug crimes (described as ’petty’, presumably referring to possession only) or drug driving, their driving licence can be revoked. In order to regain their licence the driver must prove that they have been drug-free for a given period time. As anyone working with drug offenders knows, it is relatively easy to pass a drug urine screening test: either abstain for a relatively short period or cheat the results by using someone else’e urine (there’s a black market for ‘clean’ urine — think Gattaca). When drugs are consumed, the pattern of use is recorded in hair, particularly in head hair. A Swedish study has looked at the viability of using hair analysis instead of urine analysis when assessing whether or not to return someone’s driving licence to them. Interpretation has several issues (including understanding and knowledge of the screening method limitations) but the people being tested apparently approved of hair sampling ’considering it a better means to prove their drug abstinence. In addition, both the clients and the clinicians thought hair sampling easier than urine sampling.’
(Hair analysis for drugs in driver’s license regranting. A Swedish pilot study, Pages 55-58, Robert Kronstrand, Ingrid Nyström, Malin Forsman, Kerstin Käll).
As with all cases where people have to prove drug abstinence by providing a sample of hair for analysis, it’s always interesting when they turn up to have their sample taken but have just come from the hairdressers where they had a Number 1…..

In Italy, a study has been completed to ’investigate acute and chronic exposure to environmental tobacco smoke (ETS) in a cohort of young adolescents using urinary cotinine and hair nicotine testing after recent implementation of Italian smoke free legislation,’ which has implications for everyone. The overall conclusions were that ’due to the implementation of smoke-free legislation and information campaign against smoking, a significant trend toward low exposure to ETS was observed in this study cohort with no association between exposure to ETS and respiratory illnesses.’ What I did find interesting was this: ’Hair nicotine was inversely related to educational level of the adolescents’ parents’ — not just the comment itself but the way it was phrased. It must have taken a while to phrase that appropriately…
(Assessment of exposure to environmental tobacco smoke in young adolescents following implementation of smoke-free policy in Italy, Pages 97-100, M. Pellegrini, M.C. Rotolo, S. La Grutta, F. Cibella, O. Garcia-Algar, A. Bacosi, G. Cuttitta, R. Pacifici, S. Pichini)

Finally, a French study investigated something that I find to be utterly fascinating: ’Heroin markers in hair of a narcotic police officer: Active or passive exposure?’ I think the Abstract just says it all without any need of assistance from me: In ’March 2007, a police officer (46-year-old man) and a clerk (37-year-old woman) were arrested and subjected to investigation on the charges of drugs of abuse trafficking. The loving couple was exploiting their administrative positions to make money with the resale of seized drugs. The laboratory was requested to analyse their hair for drugs of abuse. Hair of the 2 subjects tested positive for heroin by GC—MS. A few days later, analysis of hair obtained from 11 other police officers of the same unit was requested, in order to compare the results, as external contamination was proposed to account for the positive results. The aim of the investigations was to demonstrate that passive contamination could not occur for persons dealing every day with drugs of abuse with minimal caution and hygiene, and that the measured concentrations in the arrested subjects correspond to personal abuse. All the narcotic team tested negative, irrespective of the compound.’

And that’s this month’s round-up of Forensic Science International….