Hair testing is superior to urine to disclose cocaine consumption in driver's licence regranting

Distribution pattern of common drugs of abuse, ethyl glucuronide, and benzodiazepines in hair across the scalp

While hair analysis is important and accepted in forensic applications, fundamental knowledge gaps still exist, exacerbated by a lack of knowledge of the incorporation mechanisms of substances into hair. The influence of the hair sampling location on the head on ethyl glucuronide (EtG) and cocaine concentrations was investigated by measuring the complete scalp hair of 14 (2 EtG, 4 cocaine, 8 both EtG and cocaine) study participants in a grid pattern for EtG, drugs of abuse, and benzodiazepines. Head skin perfusion and sweating rates were investigated to rationalize the concentration differences. For EtG, ratios between maximum and minimum concentrations on the scalp ranged from 2.5 to 7.1 (mean 4.4). For cocaine, the ratios ranged from 2.8 to 105 (mean 17.6). EtG concentrations were often highest at the vertex, but the distribution was strongly participant dependent. Cocaine and its metabolites showed the lowest concentrations at the vertex and the highest on the periphery, especially at the forehead. These differences led to hair from some head parts being clearly above conventional cut-offs and others clearly below. In addition to EtG and cocaine, the distributions of 24 other drugs of abuse and benzodiazepines/z-substances and metabolites are described. No clear pattern was observed for the head skin perfusion. Sweating rate measurements revealed higher sweating rates on the periphery of the haircut. Therefore, sweat could be a main incorporation route for cocaine. Concentration differences can lead to different interpretations depending on the sampling site. Therefore, the results are highly relevant for routine forensic hair analysis.

Hair analysis for the detection of drug use-is there potential for evasion?

BACKGROUND

Hair analysis for illicit substances is widely used to detect chronic drug consumption or abstention from drugs. Testees are increasingly seeking ways to avoid detection by using a variety of untested adulterant products (e.g., shampoos, cleansers) widely sold online. This study aims to investigate adulteration of hair samples and to assess effectiveness of such methods.

METHODS

The literature on hair test evasion was searched for on PubMed or MEDLINE, Psycinfo, and Google Scholar. Given the sparse nature of peer-reviewed data on this subject, results were integrated with a qualitative assessment of online sources, including user-orientated information or commercial websites, drug fora and "chat rooms". Over four million web sources were identified in a Google search by using "beat hair drug test" and the first 86 were monitored on regular basis and considered for further analysis.

RESULTS

Attempts to influence hair test results are widespread. Various "shampoos," and "cleansers" among other products, were found for sale, which claim to remove analytes. Often advertised with aggressive marketing strategies, which include discounts, testimonials, and unsupported claims of efficacy. However, these products may pose serious health hazards and are also potentially toxic. In addition, many anecdotal reports suggest that Novel Psychoactive Substances are also consumed as an evasion technique, as these are not easily detectable via standard drug test. Recent changes on Novel Psychoactive Substances legislations such as New Psychoactive Bill in the UK might further challenge the testing process.

CONCLUSION

Further research is needed by way of chemical analysis and trial of the adulterant products sold online and their effects as well as the development of more sophisticated hair testing techniques.

Segmental analysis of amphetamines in hair using a sensitive UHPLC-MS/MS method

A sensitive and robust ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed and validated for quantification of amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine and 3,4-methylenedioxy methamphetamine in hair samples. Segmented hair (10 mg) was incubated in 2M sodium hydroxide (80°C, 10 min) before liquid-liquid extraction with isooctane followed by centrifugation and evaporation of the organic phase to dryness. The residue was reconstituted in methanol:formate buffer pH 3 (20:80). The total run time was 4 min and after optimization of UHPLC-MS/MS-parameters validation included selectivity, matrix effects, recovery, process efficiency, calibration model and range, lower limit of quantification, precision and bias. The calibration curve ranged from 0.02 to 12.5 ng/mg, and the recovery was between 62 and 83%. During validation the bias was less than ±7% and the imprecision was less than 5% for all analytes. In routine analysis, fortified control samples demonstrated an imprecision <13% and control samples made from authentic hair demonstrated an imprecision <26%. The method was applied to samples from a controlled study of amphetamine intake as well as forensic hair samples previously analyzed with an ultra high performance liquid chromatography time of flight mass spectrometry (UHPLC-TOF-MS) screening method. The proposed method was suitable for quantification of these drugs in forensic cases including violent crimes, autopsy cases, drug testing and re-granting of driving licences. This study also demonstrated that if hair samples are divided into several short segments, the time point for intake of a small dose of amphetamine can be estimated, which might be useful when drug facilitated crimes are investigated.

Hair as an alternative matrix in bioanalysis

Alternative matrices are steadily gaining recognition as biological samples for toxicological analyses. Hair presents many advantages over traditional matrices, such as urine and blood, since it provides retrospective information regarding drug exposure, can distinguish between chronic and acute or recent drug use by segmental analysis, is easy to obtain, and has considerable stability for long periods of time. For this reason, it has been employed in a wide variety of contexts, namely to evaluate workplace drug exposure, drug-facilitated sexual assault, pre-natal drug exposure, anti-doping control, pharmacological monitoring and alcohol abuse. In this article, issues concerning hair structure, collection, storage and analysis are reviewed. The mechanisms of drug incorporation into hair are briefly discussed. Analytical techniques for simultaneous drug quantification in hair are addressed. Finally, representative examples of drug quantification using hair are summarized, emphasizing its potentialities and limitations as an alternative biological matrix for toxicological analyses.

Workplace drug testing in Italy - critical considerations

Workplace drug testing (WDT) was established in Italy on 30 October 2007. Two tiers of survey are required: the first tier concerns drug testing on urine samples, the second involves both urine and hair analysis. Between July 2008 and December 2011, 10 598 workers' urine samples and 72 hair samples for opiates, cocaine, cannabinoids, amphetamines, methylenedioxyamphetamines, methadone, and buprenorphine were tested in our laboratory. Urine analyses were performed by immunological screening (EMIT); hair analysis and confirmation tests in urine were performed by gas chromatography-mass spectrometry (GC-MS). Employees tested positive in urine for drugs of abuse numbered 2.8% in 2008, 2.03% in 2009, 1.62% in 2010, and 1.43% in 2011. As regards the second level of analysis, we observed that only one-third of the workers who had been tested positive for drugs of abuse were referred to an Addiction Treatment Unit in order to verify drug addiction. Our experience shows that, four years after approval of the law on WDT, the percentage of workers positive for drugs of abuse in urine has reduced in comparison to the first year. Moreover, our data show that most of the times employees who tested positive are tardily referred or not referred at all to a Public Addiction Treatment Unit to verify drug addiction. This makes us believe that the legal provisions are widely disregarded not paying the right tribute to the fact that Italy is one of few European countries with legislation on WDT.

Simultaneous determination of nicotine and PAH metabolites in human hair specimen: a potential methodology to assess tobacco smoke contribution in PAH exposure

The present methodology was developed to simultaneously assess chronic exposure to PAHs and to tobacco from the analysis of one hair specimen per examined individual. The method is a two step extraction of twelve mono-hydroxy-PAHs and of nicotine, and their separate analysis by optimized methods using gas chromatography-negative chemical ionization-mass spectrometry. After method validation and assessment of the hair decontamination procedure, 105 hair specimens from smokers and non-smokers were analyzed. All the hair samples tested positive for nicotine. Median concentration was 10.7ng/mg for smokers and 0.5ng/mg for non-smokers. 70% of the samples tested positive for OH-PAHs. The most common one was 2-naphthol (61%) and its concentration was significantly higher in smokers than in non-smokers (median: 111 vs 70pmol/g, p=0.006). 2-OH-benzo(c)phenanthrene and 6-OH-chrysene were only detected once in a non-smoker's hair. The concentration of the sum of all PAH-metabolites ranged from 24 to 67190pmol/g (median: 118pmol/g). Only six samples tested positive for more than two different metabolites. The simultaneous detection of nicotine and OH-PAHs in hair is possible and provides reliable results. This represents a useful tool for the accurate biomonitoring of chronic exposure to PAH and correct identification of the sources of exposure.

Hair testing is taking root

An increasing number of toxicology laboratories are choosing to expand the services they offer to include hair testing in response to customer demands. Hair provides the toxicologist with many advantages over conventional matrices in that it is easy to collect, is a robust and stable matrix that does not require refrigeration, and most importantly, provides a historical profile of an individual's exposure to drugs or analytes of interest. The establishment of hair as a complementary technique in forensic toxicology is a direct result of the success of the matrix in medicolegal cases and the wide range of applications. However, before introducing hair testing, laboratories must consider what additional requirements they will need that extend beyond simply adapting methodologies already validated for blood or urine. Hair presents many challenges with respect to the lack of available quality control materials, extensive sample handling protocols and low drug concentrations requiring greater instrument sensitivity. Unfortunately, a common pitfall involves over-interpretation of the findings and must be avoided.

Hair: a complementary source of bioanalytical information in forensic toxicology

Hair has been used for years in the assessment and documentation of human exposure to drugs, as it presents characteristics that make it extremely valuable for this purpose, namely the fact that sample collection is performed in a noninvasive manner, under close supervision, the possibility of collecting a specimen reflecting a similar timeline in the case of claims or suspicion of a leak in the chain of custody, and the increased window of detection for the drugs. For these reasons, testing for drugs in hair provides unique and useful information in several fields of toxicology, from which the most prominent is the possibility of studying individual drug use histories by means of segmental analysis. This paper will review the unique role of hair as a complementary sample in documenting human exposure to drugs in the fields of clinical and forensic toxicology and workplace drug testing.