No abstract

No abstract

The consensus on alcohol markers in hair was revised for the fourth time by an expert group of the Society of Hair Testing based on current state of research. This revision was adopted by the members of the Society during the business meeting in Brisbane on August 29th 2016. For both markers, ethyl glucuronide (EtG) and fatty acid ethyl esters (FAEEs), two cut-off values for discrimination between teetotalers or occasional low amount consumption and moderate alcohol drinking (low cut-off), and between non-excessive (abstinence up to moderate alcohol intake) and chronic excessive drinking (high cut-off value) were critically examined. For the current revision, the cut-off values for EtG (7pg/mg and 30pg/mg, respectively) remained unchanged despite different findings or discussions published in the meantime. This was mainly due to the lack of broader data collections from new studies with great numbers of volunteers following thorough study concepts. In contrast, an essential change of the consensus was accepted for the FAEEs, where the concentration of ethyl palmitate (E16:0) can be used autonomously for interpretation instead of the concentration sum (ΣFAEE) of the four esters ethyl myristate, ethyl palmitate, ethyl oleate and ethyl stearate, as previously applied. After evaluation of the data from seven laboratories, the E16:0 cut-off for abstinence assessment was defined at 0.12ng/mg for the 0-3cm segment and at 0.15ng/mg for the 0-6cm segment. The cut-off for chronic excessive drinking was fixed at 0.35ng/mg for the 0-3cm segment and at 0.45ng/mg for the 0-6cm segment. The use of E16:0 with these cut-offs in place of ΣFAEE for alcohol intake assessment produces only a minor loss in discrimination power, leads to no essential difference in the interpretation concerning chronic excessive alcohol consumption and is suitable to confirm EtG results in abstinence assessment if ethanol containing hair sprays or lotions are excluded.

No abstract

The assessment of alcohol consumption behavior in hair is well established in forensic toxicology. The Society of Hair Testing (SoHT) recommends the direct alcohol markers ethyl glucuronide (EtG) and fatty acid ethyl esters (FAEE) for the detection of past alcohol consumption. In this study, we investigated if detox shampoos which are sold online can have an impact on EtG or FAEE concentrations in hair. According to customer reviews, positive drug testing results could be avoided after long‐term incubation with shampoo under a swimming cap. To evaluate the potential of four detox shampoos, we incubated distal hair samples from three subjects, obtained during a standard haircut, for 2.5, 5, 7.5, and 10 hours. For EtG, three shampoos performed similar to deionized water. The fourth shampoo showed additional heavy washout effects with a decrease of up to 86% after 2.5 hours. For the apolar FAEE, no washout was observed. Incubation with two shampoos resulted in increases in FAEE concentrations due to FAEE being present as shampoo ingredients. Further investigation of EtG washout in proximal forensic hair samples (n = 9) with the most potent shampoo showed a mean decrease in deionized water of 23% ± 25%, and a decrease by the use of detox shampoo of 73% ± 12%, compared to non‐incubated hair after 8 hours. In conclusion, detox shampoos proved to have the potential to alter EtG and FAEE concentrations in hair during in vitro experiments.