Can ethyl glucuronide in hair be determined only in 3 cm hair strands?

This paper addresses the suitability of ethyl glucuronide in hair (EtGH) strands other than 3 cm for alcohol consumption. This issue will be addressed (a) by statistically comparing the distribution of EtGH results for 3 cm hair strands to other hair strands analysed from 4126 cases and (b) by examining the stability of EtGH in an 8 cm hair strand and two 12 cm hair samples of two volunteers and a post-mortem case using 1 cm segmental analysis. For 3464 driving license re-granting Medical and Psychological Assessment (MPA) cases, the detection of alcohol consumption using hair lengths longer than 3 cm was never significantly less than for 3 cm hair lengths, even up to 12 cm hair lengths analysed non-segmented. For 662 non-MPA cases, where, in contrast to MPA cases, generally no abstinence was required, an increase in the EtGH positivity rate was observed with increasing hair length analysed up to 9 cm, indicating that EtG-washout effects seem to play a minor role if any. For both MPA and non-MPA hair samples less than 3 cm, a drastic, significant increase in the number of positive EtGH samples were observed, compared to 3 cm hair lengths, strongly supportive of EtGH incorporation from sweat after a recent alcohol consumption. Segmental studies indicated that EtG is stable in the hair matrix up to 12 cm long, hence supporting the above results. Even though both the statistical and the stability studies are preliminary results which need to be confirmed by other studies, they both provide evidence for the determination of alcohol consumption using EtGH in hair lengths longer than 3 cm. Amendments to the Consensus of the Society of Hair Testing, the German driving license re-granting guidelines and EWDTS hair guidelines with respect to testing for abstinence and/or alcoholism are proposed for the benefit of the donors.