SOFT 2004 Meeting Abstracts - Society of Forensic Toxicologists

M35
DRUG DETECTION IN HAIR: ASSESSMENT OF LEVELS FROM LARGE VOLUME SCREENING AND
CONFIRMATION TESTING
John Wicks*, John Sullivan and Lolita Tsanaclis: Tricho-Tech Limited, The Cardiff Medicentre, Heath Park, Cardiff,
CFI4 4UJ, United Kingdom.
In recent years understanding of the benefits of the use of hair in drug testing has increased, particularly its advantages
over urine, and more recently, oral fluid. The key benefit is the long time window of detection. This understanding
together with reliable techniques has contributed to the dramatic increase in the use of hair samples in the detection of
drug use. Amongst the wide variety of sectors that currently use hair for the detection of drugs, the largest are clinics,
family law firms, the police and various organisations for workplace testing. The main purpose is to verifY drug use or
monitor drug abstinence. Very often when the analysis is performed and the results issued, the most common question
that is raised is: what do the levels detected tell me about how much drugs were used by the person being tested
Because it is difficult to establish an accurate estimation of the amount of dose taken in relation to levels of drug in
hair, the levels of drugs detected in hair are best used as a guide to changes in use in the individual when sectional
analysis is performed or two different periods are compared in the same individual.
Nonetheless, it can be very useful, as a guide when writing reports or communicating with clients, to compare results
obtained from a hair test from an individual's hair sample with results obtained in other samples from a large group of
people. Hair samples (N=12,218) from various sources were received by Tricho-Tech for screening for drugs over a
two-year period and analysed using the same method. All samples were washed, extracted then screened using coatedplate
ELISA test for each drug group (Immunalysis Corporation, Pomona, CA, USA) and processed by an automated
analyser Triturus (Grifols, Cambridge, UK) at a cut-off of 0.5 ng/mg (Table I). Samples above the cut-off were
submitted for confirmation analysis by Gas Chromatography-Mass Spectrometry (GC-MS or GC-MS/CI) using
HP5973 (Agilent, Berkshire, UK) or Varian Inc. Saturn for GC-MS/MS (Walton-on-Thames, UK). The dynamic range
was from 2 to 160 ng/mL. Three ions for the drugs and two ions for the internal standards were monitored.
Tabl e I H' air samples analyse dbJy ELISA and GCMS WI·th confiIrmatlOn rates or eac hdruJg group.
I iScreened GCMS Confirmation Rate
i
i Group .N
N % N %
Amphetamines 7355 4128 (56%) 1839 (45%)
Benzodiazepines 5804 1879 (32%)
Buprenorphine 786
1415 (75%)
113 (14%) 63 (56%)
Cocaine 8919 3150 (35%) 2490 (79%)
Methadone 6127 .1893 (31%)
1666 (88%)
Opiates 8970 4164
1
J46%) 2901 -.i70o/~
Percentiles 25%, 50% (Median), 75%, 95% and maximum levels for all analytes in each drug group were calculated
and will be presented. Results for Cocaine Group are shown in Table 2.
Percentiles and maximum levels in n m of hair for Cocaine rou
25% 50% 75% 95% Maximum N
0.3 0.8 1.6 5.5 34.8 305
i""WY',,,,,,i",
Cocaethylene 0.3 0.5 1.2 4.1 9.4 339
0.4 1.1 3.6 16.5 163.7 1988
Cocaine 0.9 2.9 11.9 59.5 814.2 2483
Using Cocaine as an example of drug levels by sector, median levels were: Clinical=6.9 ng/mg; Police=5.0 ng/mg;
Medico-Legal=2.5 ng/mg and Employment =0.4 ng/mg. A consistent pattern was seen for the other drug groups.
The results show a wide range of levels for all analytes, frequency and distribution. Thus, this assessment of levels
provides an important comparative aid for interpreting results of detected drugs in samples of hair.
Keywords: Drugs, Hair, GC-MS/MS
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