Can Drunk Driving Arrests May Be Supported through Swabbing Your Forehead for Sweat?
William C. Head, DUI
Litigation Specialist
Senior Partner, Head, Thomas, Webb & Willis, LLC
Atlanta, GA, USA
An international effort to identify impaired drivers (drugs and
alcohol) has led to new efforts to estimate both alcohol quantities as
well as certain illegal drugs in persons who engage in risky driving
who might be stopped at roadside sobriety checkpoints. Breath
analysis equipment is generally limited to alcohol detection and
quantitfication. Drugs have become an increasingly difficult
impairment problem for police. Once reliability has been improved,
expect to have police officers request a "sweat sample" from your
forehead, to determine whether you may be impaired by drugs or alcohol
or BOTH alcohol and drugs.
The following summary of scientific studies regarding "sweat" sampling
was complied by Dr. Robert Forrest, a government physician (who is
also trained as an attorney) located in Great Britain, has complied
the following summary of preliminary studies regarding "sweat"
sampling. New techniques and possibly bio-mechanical devices used to
identify intoxicated or drug-impaired drivers will be deployed in this
decade.
Drugs in Sweat.
N. Samyn, G. De
Boeck and A. G. Verstraete (2002). "The use of oral fluid and sweat wipes
for the detection of drugs of abuse in drivers." Journal of Forensic
Sciences 47(6): 1380-7.
Blood,
urine, oral fluid (by spitting or with a Salivette), and sweat samples (by
wiping the forehead with a fleece moistened with isopropanol) were
obtained from 180 drivers who failed the field sobriety tests at police
roadblocks. With quantitative GC-MS, the positive predictive value of oral
fluid was 98, 92, and 90% for amphetamines, cocaine, and cannabis
respectively. The prevalence of opiate positives was low. The proposed
SAMHSA cut-off values for oral fluid testing at the workplace, proved
their usefulness in this study. The positive predictive value of sweat
wipe analysis with GC-MS was over 90% for cocaine and amphetamines and 80%
for cannabis. The accuracy of Drugwipe was assessed by comparing the
electronic read-out values obtained on-site after wiping the tongue and
the forehead, with the corresponding GC-MS results in plasma, oral fluid,
and sweat. The accuracy was always less than 90% except for the
amphetamine-group in sweat.
O. Y. Al-Dirbashi,
K. Ikeda, M. Takahashi, N. Kuroda, S. Ikeda and K. Nakashima (2001).
"Drugs of abuse in a non-conventional sample; detection of methamphetamine
and its main metabolite, amphetamine in abusers' clothes by HPLC with UV
and fluorescence detection." Biomedical Chrmatography 15(7):
457-63.
In
this paper, we report the detection of methamphetamine and its major
metabolite, amphetamine, in garments belong to known-abusers. These
compounds were extracted from the textile using a mixture of
chloroform:propan-2-ol (3:1, v/v), derivatized with
4-(4,5-diphenyl-1H-imidazol-2-yl) benzoyl chloride and separated using a
reversed-phase high-performance liquid chromatography. The derivatives
were detected by measuring either fluorescence at 440 nm or absorbance at
330 nm. By using 1-methyl-3-phenyl propylamine as an internal standard,
calibration curves of spiked textile samples were linear over a wide range
with correlation coefficients of 0.997 or better. Detection limits at a
signal-to-noise ratio of 3 were less than or equal to 37.3 and 0.4 pg on
column for the high-performance liquid chromatography-ultraviolet and
-fluorescence detection methods, respectively. Intra- and inter-day
variations at high and low concentrations (n > or = 3) were < or =12.7%.
The developed methods were successfully applied to the determination of
methamphetamine and amphetamine in clothes samples belong to abusers.
Copyright 2001 John Wiley & Sons, Ltd.
D. J. Crouch, R.
F. Cook, J. V. Trudeau, D. C. Dove, J. J. Robinson, H. L. Webster and A.
A. Fatah (2001). "The detection of drugs of abuse in liquid perspiration."
Journal of Analytical Toxicology 25(7): 625-7.
D. E. Moody and M.
L. Cheever (2001). "Evaluation of immunoassays for semiquantitative
detection of cocaine and metabolites or heroin and metabolites in extracts
of sweat patches." Journal of Analytical Toxicology 25(3):
190-7.
Two
types of immunoassays, radioimmunoassay (RIA) and microplate enzyme
immunoassay (EIA), were compared for their ability to detect and
quantitate cocaine and metabolites or heroin and metabolites in extracts
of sweat patches. Experiments used sweat patches that had been fortified
with cocaine, benzoylecgonine (BE), and ecgonine methyl ester (EME) or
6-acetylmorphine (6-AM), heroin, and morphine. Assays were first evaluated
for sensitivity in detection of the analyte(s) known to be excreted in
sweat (cocaine >> BE and EME; 6-AM > heroin > morphine). The cocaine
metabolite RIA had cross-reactivity for cocaine > BE > EME, and the
cocaine metabolite EIA had cross-reactivity for BE > cocaine >> EME. The
RIA, having greater sensitivity for COC, was studied further. Optimal
linearity was 4 to 200 ng/patch, and quantitation within these limits at
4, 75, and 150 ng/patch had intrarun %CVs within 7.8% and percent targets
within 15% and inter-run %CVs within 13.5% and % targets within 13%. The
opiate RIA had cross-reactivities for morphine >> 6-AM and heroin. The
opiate EIA had cross-reactivities for 6-AM and heroin of 42 and 28%
relative to morphine, respectively. The EIA, having greater sensitivity
for 6-AM and heroin, was studied further. The limits of detection ranged
from 1.7 to 24.7 ng/patch, and the lower limits of quantitation ranged
from 7.3 ng/patch to beyond the linear range. The assay, however, had
consistently good precision at 4 and 5 ng/patch, and optimal linearity was
established from 4 to 100 ng/patch. With controls at 5, 25, and 90 ng/patch,
both intrarun and inter-run precision were acceptable. Quantitation was
accurate at 5 and 25 ng/patch, but the 90 ng/patch controls were
consistently < 70% of target. Because our studies focused on the assays
that had greater sensitivity for the analytes excreted in sweat, we did
not fully evaluate the cocaine metabolite EIA or the RIA opiate screen and
therefore cannot make any comment on the usefulness of these assays for
detecting analytes in extracts of sweat patches beyond predicting that
they will have less sensitivity. Both the cocaine metabolite RIA and
opiate EIA had the ability to detect analytes known to be extracted from
sweat patches.
R. Pacifici, M.
Farre, S. Pichini, J. Ortuno, P. N. Roset, P. Zuccaro, J. Segura and R. de
la Torre (2001). "Sweat testing of MDMA with the Drugwipe analytical
device: a controlled study with two volunteers." Journal of Analytical
Toxicology 25(2): 144-6.
Rapid
on-site tests for the analysis of drugs of abuse in unconventional
specimens (e.g., sweat) have recently been developed. Two healthy
volunteers familiar with the effects of methylenedioxymethamphetamine (MDMA)
were given 100 mg of the drug as a single oral dose. MDMA and its main
metabolite 4-hydroxy-3-methoxymethamphetamine (HMMA) were determined in
plasma and urine by gas chromatography-mass spectrometry (GC-MS). MDMA was
also investigated in sweat with the Drugwipe (an immunochemical strip
test). Subjects' armpits were swabbed for 10 s at 0 time (predose) and at
2, 6, 8, 12, and 24 h after MDMA administration. MDMA consumption could be
detected using Drugwipe at 2 h and for as long as 12 h after drug
administration. However, in one of the volunteers, a faint color change
appeared at 0 time, when plasma and urine tested negative for MDMA and did
not disappear even 48 h later. Plasma concentrations of MDMA and HMMA
measured by GC-MS peaked at 2-4 h, and values greater than 20 ng/mL for
MDMA and of 40 ng/mL for HMMA were still detected at 24 h. Urine tested
positive by GC-MS for MDMA and HMMA in the 48-h collection period. These
findings preliminarily support sweat testing with Drugwipe for monitoring
MDMA use.
Y. H. Caplan and
B. A. Goldberger (2001). "Alternative specimens for workplace drug
testing." Journal of Analytical Toxicology 25(5): 396-9.
Recent
advances in analytical techniques have enabled the detection of drugs and
drug metabolites in alternative biological specimens for the purposes of
workplace testing. A wide variety of specimens are available, each
providing valuable information concerning prior or current drug use. The
present focus is on oral fluid (saliva), hair, and sweat. An extensive
evaluation by the Division of Workplace Programs of the Department of
Health and Human Services is underway to determine the utility of these
specimens in federally regulated programs. In future years, the testing of
alternative specimens will expand our ability to understand the patterns
of drug use and will become routine in all areas of forensic toxicology.
[References: 6]
D. A. Kidwell and
F. P. Smith (2001). "Susceptibility of PharmChek drugs of abuse patch to
environmental contamination." Forensic Science International.
116(2-3): 89-106.
The
key component of the PharmChek sweat patch, the membrane, has been tested
for the passage of externally applied materials. Drugs in the uncharged
state rapidly penetrated the membrane but charged species were greatly
slowed. In basic media, detectable concentrations of cocaine,
methamphetamine, and heroin were observed at the earliest collection time
(ca. 30 s), after drugs were placed on the outside of the membrane. Drug
concentrations increased over the 2 h time course, when amounts detected
(1710 ng cocaine, 1060 ng methamphetamine, 550 ng heroin per pad at 2 h)
represented 5-17% of the drug deposited on the surface of the sweat
patch.Drugs externally applied to human skin were shown to bind readily.
Drugs deposited on the skin of drug-free volunteers several days prior to
application of the sweat patch were not completely removed by normal
hygiene or the cleaning procedures recommended before application of the
sweat patch. Even 6 days of normal hygiene did not remove all drugs from
externally contaminated skin and positive sweat patches resulted. A
mechanism for passage of drugs through the sweat patch membrane, a
mechanism for retention of drugs on skin, and a redesign of the sweat
patch and modification of its use to reduce external contamination are
proposed. Appropriate care should be taken in the interpretation of
positive results from a sweat patch test until more research is conducted.
V. Spiehler (2000
Jan 10). "Hair analysis by immunological methods from the beginning to
2000." Forensic Science International. 107(1-3): 249-59.
Immunoassays for hair testing must satisfy three requirements: (1) They
must have cross-reactivity with parent drug and lipophilic metabolites
actually found in hair (2) they must not experience interference from the
dissolved hair matrix and (3) they must be titered for cutoffs appropriate
to the drug concentrations found in hair. Because the analytes found in
hair after drug use are generally the parent drug or its lipophilic
metabolites, immunoassays developed and intended for urine testing are not
suitable for hair. Immunoassays whose antibodies are bound to a solid
support, such as coated-tube radioimmunoassay or coated-plate ELISA tests,
experience less matrix interference than those which use other means of
separation of bound and free fractions. Homogenous assays are not suitable
for hair testing because the hair matrix frequently interferes in the
detection of the signal. Historically radioimmunoassays for drugs of abuse
were first used for detecting drugs in hair. Currently ELISAs and
coated-plate 96 well microplate EIAs are employed for screening hair
digests or extracts for drugs. The optimum cutoffs for immunoassays for
drugs in hair should be chosen based on the analyte concentration which
produces the fewest false positive or false negative results when applied
to tests of hair from known users and non-users of drugs. A hair
immunoassay test at these cutoffs should have a sensitivity and
specificity of better than 90%. The predictive value of the test will
depend on the prevalence of drug use in the tested population. Cutoffs or
decision thresholds for immunoassays used for screening for drugs should
not be at the limit of detection of the assay because that produces a very
large incidence of false positives. Because immunoassays are ligand-binding
assays, they have a short range of linearity with low precision at both
ends of the range. In the future, immunoassays will continue to be used
for screening hair and other matrices for drugs of abuse because they
provide rapid, inexpensive automated procedures for separating negative
specimens from those which are suspected of containing drugs. For forensic
purposes, all positive results must be confirmed by an independent
analysis using a procedure based on a different property of the analyte.
An immunoassay test should not be confirmed by a second immunoassay test
but by a chromatographic test performed on a different dissolved or
extracted aliquot of the original specimen. [References: 24]
M. A. Huestis, E.
J. Cone, C. J. Wong, A. Umbricht and K. L. Preston (2000). "Monitoring
opiate use in substance abuse treatment patients with sweat and urine drug
testing." Journal of Analytical Toxicology 24(7): 509-21.
Although urine testing remains the standard for drug use monitoring, sweat
testing for drugs of abuse is increasing, especially in criminal justice
programs. One reason for this increase is sweat testing may widen the
detection window compared to urine testing. Drug metabolites are rapidly
excreted in urine limiting the window of detection of a single use to a
few days. In contrast, sweat collection devices can be worn for longer
periods of time. This study was designed to compare the efficacy of sweat
testing versus urine testing for detecting drug use. Paired sweat patches
that were applied and removed weekly on Tuesdays were compared to 3-5
consecutive urine specimens collected Mondays, Wednesdays, and Fridays
(355 matched sweat and urine specimen sets) from 44 patients in a
methadone-maintenance outpatient treatment program. All patches (N = 925)
were extracted in 2.5 mL of solvent and analyzed by ELISA immunoassay for
opiates (cutoff concentration 10 ng/mL). A subset (N = 389) of patches was
analyzed by gas chromatography-mass spectrometry (GC-MS). Urine specimens
(N = 1886) were subjected to qualitative analysis by EMIT (cutoff 300 ng/mL).
Results were evaluated to (1) determine the identity and relative amounts
of opiates in sweat; (2) assess replicability in duplicate patches; (3)
compare ELISA and GC-MS results for opiates in sweat; and (4) compare the
detection of opiate use by sweat and urine testing. Opiates were detected
in 38.5% of the sweat patches with the ELISA screen. GC-MS analysis
confirmed 83.4% of the screen-positive sweat patches for heroin,
6-acetylmorphine, morphine, and/or codeine (cutoff concentration 5 ng/mL)
and 90.2% of the screen-negative patches. The sensitivity, specificity,
and efficiency of ELISA opiate results as compared to GC-MS results in
sweat were 96.7%, 72.2%, and 89.5%, respectively. Heroin and/or
6-acetylmorphine were detected in 78.1% of the GC-MS-positive sweat
patches. Median concentrations of heroin, 6-acetylmorphine, morphine, and
codeine in the positive sweat samples were 10.5, 13.6, 15.9, and 13.0 ng/mL,
respectively. Agreement in paired sweat patch test results was 90.6% by
ELISA analysis. For the purposes of this comparison of ELISA sweat patch
to EMIT urine screening for opiates, the more commonly used urine test was
considered to be the reference method. The sensitivity, specificity, and
efficiency of sweat patch results to urine results for opiates were 68.6%,
86.1%, and 78.6%, respectively. There were 13.5% false-negative and 7.9%
false-positive sweat results as compared to urine tests. Analysis of sweat
patches provides an alternate method for objectively monitoring drug use
and provides an advantage over urine drug testing by extending drug
detection times to one week or longer. In addition, identification of
heroin and/or 6-acetylmorphine in sweat patches confirmed the use of
heroin in 78.1% of the positive cases and differentiated illicit heroin
use from possible ingestion of codeine or opiate-containing foods.
However, the percentage of false-negative results, at least in this
treatment population, indicates that weekly sweat testing may be less
sensitive than thrice weekly urine testing in detecting opiate use.
L. Rivier (2000).
"Techniques for analytical testing of unconventional samples." Best
Practice & Research Clinical Endocrinology & Metabolism. 14(1):
147-65.
Forensic scientists have long detected the presence of drugs and their
metabolites in biological materials using body fluids such as urine, blood
and/or other biological liquids or tissues. For doping analysis, only
urine has so far been collected. In recent years, remarkable advances in
sensitive analytical techniques have encouraged the analysis of drugs in
unconventional biological samples such as hair, saliva and sweat. These
samples are easily collected, although drug levels are often lower than
the corresponding levels in urine or blood. This chapter reviews recent
studies in the detection of doping agents in hair, saliva and sweat.
Sampling, analytical procedures and interpretation of the results are
discussed in comparison with those obtained from urine and blood samples.
[References: 76]
N. Samyn and C.
van Haeren (2000). "On-site testing of saliva and sweat with Drugwipe and
determination of concentrations of drugs of abuse in saliva, plasma and
urine of suspected users." International Journal of Legal Medicine.
113(3): 150-4.
Potential drug users participated voluntarily in a Belgian study on the
usefulness of the non-instrumental immunoassay Drugwipe (Securetec,
Germany) for the screening of cocaine, opiates, amphetamine and
cannabinoids in saliva and sweat. If one of the screening assays (urine,
oral fluid, sweat) showed a positive result, blood and saliva were
collected. The on-site Drugwipe results were correlated with the Drugwipe
results for saliva in the laboratory and with the GC/MS results of the
corresponding saliva, plasma and urine samples and pharmacological effects
at the time of sampling. The Drugwipe assay proved to be sufficiently
sensitive for the detection of recent cocaine (n = 6) and amphetamine (n =
15) abuse, whether the device was wiped on the tongue or on the surface of
the body, or when a saliva sample was applied to the wiping part. In five
of the six potential cocaine users, the saliva concentrations of cocaine
exceeded 1,000 ng/ml. In the amphetamine group, the saliva concentrations
of amphetamine, MDMA or both were high (> 1,000 ng/ml) in 13 subjects. For
cocaine and amphetamine, the positive scores for Drugwipe matched the
GC/MS results for the three body fluids. Recent heroin abuse (n = 5) could
be demonstrated to some extent with Drugwipe on samples from the tongue
but only the two subjects with the highest saliva concentrations of MAM (>
500 ng/ml) and morphine (> 500 ng/ml) were positive. If the legal cut-off
value for driving under the influence of opiates in Belgium (20 ng/ml of
free morphine in plasma) was taken into account, only three subjects would
have been legally positive. For cannabinoids (n = 15), false negatives and
even some false positives were observed. Saliva can be considered as a
useful analytical matrix for the detection of drugs of abuse after recent
abuse when analysed with GC/MS.
J. A. Levisky, D.
L. Bowerman, W. W. Jenkins and S. B. Karch (2000). "Drug deposition in
adipose tissue and skin: evidence for an alternative source of positive
sweat patch tests." Forensic Science International. 110(1):
35-46.
In a
series of licit and illicit drug-related deaths, qualitative and
quantitative analyses on extracts of adipose tissue and skin were
performed by GC/MS. In all cases, the adipose tissue was found to contain
drugs at concentrations lower than, approximately equal to, or even
greater than the concentrations of the same analytes found in the blood,
which may reflect a consequence of long-term chronic exposure, or acute
intoxication, or some combination of both. Approximately one cubic inch of
skin with adipose tissue was removed from the mid to lower abdominal
region adjacent to the midline incision during autopsy. The drugs were
recovered from the specimens following incubation and alkaline, acidic,
and alkaline chloroform back extraction of one to three grams of tissue.
Deuterated analogs of the analytes were added to the matrix at the
beginning of the incubation period. Cocaine and free morphine (from
heroin) were readily identified in several cases. The presence of these
illicit drugs in adipose tissue raises significant forensic questions,
especially the use of 'sweat patches' to monitor recent cocaine or heroin
use in chronic drug users.
P. Kintz, V.
Cirimele and B. Ludes (2000). "Detection of cannabis in oral fluid
(saliva) and forehead wipes (sweat) from impaired drivers." Journal of
Analytical Toxicology 24(7): 557-61.
Saliva
and sweat have been presented as two alternative matrices for the
establishment of drug abuse. The noninvasive collection of a saliva or
sweat sample, which is relatively easy to perform and can be achieved
under close supervision, is one of the most important benefits in a
driving-under-the-influence situation. Moreover, the presence of certain
analytes in saliva is a better indication of recent use than when the drug
is detected in urine, so there is a higher probability that the subject is
experiencing pharmacological effects at the time of sampling. We developed
an original procedure using gas chromatography-mass spectrometry to test
for delta9-tetrahydrocannabinol (THC), the psychoactive ingredient of
cannabis, in oral fluid and forehead wipes, collected with Sarstedt
Salivettes and cosmetic pads, respectively. Blood, urine, oral fluid, and
forehead wipes were simultaneously collected from 198 injured drivers
admitted to an Emergency Hospital in Strasbourg, France. Of the 22
subjects positive for 11-nor-9-carboxy-THC (THCCOOH) in urine, 14 and 16
were positive for THC in oral fluid (1 to 103 ng/Salivette) and forehead
wipe (4 to 152 ng/pad), respectively. 11-Hydroxy-THC and THCCOOH were not
detected in these body fluids. Two main limitations of saliva and sweat
are apparent: the amount of matrix collected is smaller when compared to
urine, and the levels of drugs are higher in urine than in saliva and
sweat. A current limitation in the use of these specimens for roadside
testing is the absence of a suitable immunoassay that detects the parent
compound in sufficiently low concentrations.
D. E. Moody
(2000). "Units for sweat patch results.[comment]." Journal of
Analytical Toxicology 24(8): 733.
R. E. Joseph, Jr.,
K. M. Hold, D. G. Wilkins, D. E. Rollins and E. J. Cone (1999). "Drug
testing with alternative matrices II. Mechanisms of cocaine and codeine
deposition in hair." Journal of Analytical Toxicology. 23(6):
396-408.
A
10-week inpatient study was performed to evaluate cocaine, codeine, and
metabolite disposition in biological matrices collected from volunteers.
An initial report described drug disposition in plasma, sebum, and stratum
corneum collected from five African-American males. This report focuses on
drug disposition in hair and sweat collected from the same five subjects.
Following a three-week washout period, three doses of cocaine HCl (75
mg/70 kg, subcutaneous) and three doses of codeine SO4 (60 mg/70 kg, oral)
were administered on alternating days in week 4 (low-dose week). The same
dosing sequence was repeated in week 8 with doubled doses (high-dose
week). Hair was collected by shaving the entire scalp once each week. Hair
from the anterior vertex was divided into two portions. One portion was
washed with isopropanol and phosphate buffer; the other portion was not
washed. Hair was enzymatically digested, samples were centrifuged, and the
supernatant was collected. Sweat was collected periodically by placing
PharmChek sweat patches on the torso. Drugs were extracted from sweat
patches with methanol/0.2 M sodium acetate buffer (75:25, v/v).
Supernatants from hair digests, hair washes, and sweat patch extracts were
processed by solid-phase extraction followed by gas chromatography-mass
spectrometry analysis for cocaine, codeine, 6-acetylmorphine, and
metabolites. Cocaine and codeine were the primary analytes identified in
sweat patches and hair. Drugs were detected in sweat within 8 h after
dosing, and drug secretion primarily occurred within 24 h after dosing. No
clear relationship was observed between dose and drug concentrations in
sweat. Drug incorporation into hair appeared to be dose-dependent. Drugs
were detected in hair within 1-3 days after the last drug administration;
peak drug concentrations generally occurred in the following 1-2 weeks;
thereafter, drug concentrations decreased. Solvent washes removed 50-55%
of cocaine and codeine from hair collected 1-3 days after the last drug
dose. These data may reflect removal of drug that was deposited by sweat
shortly after dosing. Drug removed by washing hair collected 1-3 weeks
after the last dose was minimal for cocaine but variable for codeine. Drug
in these specimens was likely transferred from blood to germinative hair
cells followed by emergence of drug in growing hair. These findings
suggest that drug deposition in hair occurs by multiple mechanisms.
K. L. Preston, M.
A. Huestis, C. J. Wong, A. Umbricht, B. A. Goldberger and E. J. Cone
(1999). "Monitoring cocaine use in substance-abuse-treatment patients by
sweat and urine testing.[comment]." Journal of Analytical Toxicology.
23(5): 313-22.
Sweat
and urine specimens were collected from 44 methadone-maintenance patients
to evaluate the use of sweat testing to monitor cocaine use. Paired sweat
patches that were applied and removed weekly (on Tuesdays) were compared
with 3-5 consecutive urine specimens collected Mondays, Wednesdays, and
Fridays. All patches (N = 930) were extracted in 2.5 mL of solvent and
analyzed by ELISA immunoassay (cutoff concentration 10 ng/mL); a subset of
patches (N = 591) was also analyzed by gas chromatography-mass
spectrometry (GC-MS) for cocaine, benzoylecgonine (BZE), and ecgonine
methyl ester (EME) (cutoff concentration 5 ng/mL). Urine specimens were
subjected to qualitative analysis by EMIT (cutoff 300 ng/mL) and subsets
were analyzed by TDx (semiquantitative, LOD 30 ng/mL) and by GC-MS for
cocaine (LOD 5 ng/mL). Results were evaluated to (1) determine the
relative amounts of cocaine and its metabolites in sweat; (2) assess
replicability in duplicate patches; (3) compare ELISA and GC-MS results
for cocaine in sweat; and (4) compare the detection of cocaine use by
sweat and urine testing. Cocaine was detected by GC-MS in 99% of
ELISA-positive sweat patches; median concentrations of cocaine, BZE, and
EME were 378, 78.7, and 74 ng/mL, respectively. Agreement in duplicate
patches was approximately 90% by ELISA analysis. The sensitivity,
specificity, and efficiency of sweat ELISA cocaine results as compared
with sweat GC-MS results were 93.6%, 91.3%, and 93.2%, respectively. The
sensitivity, specificity, and efficiency between ELISA sweat patch and
EMIT urine results were 97.6%, 60.5%, and 77.7%, respectively. These
results support the use of sweat patches for monitoring cocaine use,
though further evaluation is needed.
G. Skopp and L.
Potsch (1999). "Perspiration versus saliva--basic aspects concerning their
use in roadside drug testing." International Journal of Legal Medicine.
112(4): 213-21.
Various aspects concerning the practical application and forensic
interpretation of data obtained by saliva drug testing and drug monitoring
from the skin surface are discussed. Basic information on the composition
of saliva and skin secretions and their particular transport mechanisms,
as far as known, are given. For drugs of abuse secretion into saliva is
suggested to be by passive diffusion and to depend on lipid solubility,
pKa, plasma protein binding and on the pH of saliva. Drug molecules from
blood are considered to reach the skin surface by various routes such as
by sweat and sebum as well as by inter- and/or transcellular diffusion.
The role of the stratum corneum as a temporary drug reservoir exceeding
positive drug findings in urine is outlined. Current data on opioids,
cocaine metabolites, cannabinoids and amphetamines detected in saliva and
on the skin surface are reviewed. Aspects of collection, processing and
analysis of the samples for implementation in roadside testing are
addressed. The requirement of test sensitivity covering the broad
concentration ranges and the importance of test specificity bearing in
mind that the parent drug is the main analyte present in those specimens
is stressed. Theoretical and practical findings on frequently abused drugs
are discussed with regard to the possibilities and limitations of drug
monitoring from saliva and perspiration to support a suspicion of actual
or recent drug administration. [References: 74]
D. A. Kidwell, J.
C. Holland and S. Athanaselis (1998). "Testing for drugs of abuse in
saliva and sweat.[erratum appears in J Chromatogr B Biomed Sci Appl 1999
Jan 22;721(2):333]." Journal of Chromatography. B, Biomedical Sciences
& Applications 713(1): 111-35.
The
detection of marijuana, cocaine, opiates, amphetamines, benzodiazepines,
barbiturates, PCP, alcohol and nicotine in saliva and sweat is reviewed,
with emphasis on forensic applications. The short window of detection and
lower levels of drugs present compared to levels found in urine limits the
applications of sweat and saliva screening for drug use determination.
However, these matrices may be applicable for use in driving while
intoxicated and surveying populations for illicit drug use. Although not
an illicit drug, the detection of ethanol is reviewed because of its
importance in driving under the influence. Only with alcohol may saliva be
used to estimate blood levels and the degree of impairment because of the
problems with oral contamination and drug concentrations varying depending
upon how the saliva is obtained. The detection of nicotine and cotinine
(from smoking tobacco) is also covered because of its use in life
insurance screening and surveying for passive exposure. [References: 217]
P. Kintz, V.
Cirimele and B. Ludes (1998). "Codeine testing in sweat and saliva with
the Drugwipe." International Journal of Legal Medicine 111(2):
82-4.
With
the growing interest in drug testing within different sectors of society,
there has become a need for drug assays that can be performed immediately
at the site of specimen collection. Recently, Securetec (Ottobrunn,
Germany) has introduced the Drugwipe, a non instrument-based, on-site
immunodiagnostic assay for the detection of drugs on surfaces. Different
tests are available for opiates, cocaine and cannabis. To document the
applications of the Drugwipe "opiate" on human biological fluids, 60 mg
codeine phosphate were orally administered to 6 subjects. First, sweat
testing with the Drugwipe was studied. The wiping section of the kit was
used to swab the forehead of the subjects for 10 s, at 1, 4, 9 and 24 h
after codeine administration. At the same time, for each period, a sweat
patch (Pharmchek, USA) was applied to the outer portion of the upper arm.
Codeine was then quantified in the patch by GC/MS and the measured
concentrations used as reference. In all subjects except one the Drugwipe
tested positive for opiates, however with few false negative results. In
the second part of the study, results of the Drugwipe were compared with
those obtained by GC/MS for saliva. The tongue of the subjects was
carefully wiped over a period 24 h, and at the same time a specimen of
saliva collected. Although codeine could be detected using the Drugwipe,
numerous false negative results were observed. Codeine tested positive by
GC/MS but remained negative using the Drugwipe in several cases. This can
be explained by a codeine concentration which was too low to show positive
with the Drugwipe, interfering substances may be present in saliva or the
sampling procedure is inadequate.
P. Kintz, A.
Tracqui, C. Marzullo, A. Darreye, F. Tremeau, P. Greth and B. Ludes
(1998). "Enantioselective analysis of methadone in sweat as monitored by
liquid chromatography/ion spray-mass spectrometry." Therapeutic Drug
Monitoring 20(1): 35-40.
In
recent years, remarkable advances in sensitive analytical techniques have
enabled the analysis of drugs in unconventional samples, such as sweat. In
a study conducted during a methadone maintenance program, PharmChek sweat
patches were applied to 20 subjects. The subjects were orally administered
methadone in 1 dosage/day, and doses ranged from 80 to 100 mg. The sweat
patch was applied 10 minutes before administration and removed 72 hours
later just before a new administration of methadone. The absorbent pad was
stored at -20 degrees C until analysis in plastic tubes. Methadone was
extracted in 5 ml methanol in presence of 200 ng of racemic methadone-d3,
used as internal standard. After a 30-minute agitation, the methanol
solution was evaporated to dryness. Enantioselective separation of
methadone was obtained using an alpha-1-acid glycoprotein column (100 x 4
mm ID) and liquid chromatography/ion spray-mass spectrometry. In all 20
specimens obtained from subjects under racemic methadone treatment, R-
(the active form) and S-enantiomers of methadone were identified with the
following concentrations: 26 to 1118 ng/patch for R-methadone and 28 to
1114 ng/patch for S-methadone. The ratio between R- and S-methadone was in
the range of 0.72 to 2.66 and was higher than 1.00 in 15 samples. No
correlation between the doses of methadone administered and the
concentrations of methadone in sweat was observed.
D. S. Shearer, G.
J. Baciewicz and T. C. Kwong (1998). "Drugs of abuse testing in a
psychiatric outpatient service." Clinics in Laboratory Medicine
18(4): 713-26.
Drug
testing of patients in a psychiatric outpatient service is an effective
way to identify patients who relapse into renewed use of drugs of abuse
and in monitoring the effectiveness of ongoing medical and psychological
therapy. Most of this testing involves the analysis of urine specimens
with immunoassays. Hair testing affords an alternative specimen matrix
that is easy to obtain and not readily adulterated and offers the
advantage of a wider surveillance window. Hair analysis is technically
demanding, and the possibility of false-positives caused by environmental
contamination renders it a controversial alternative. Sweat and saliva are
potentially useful testing matrices, but their usefulness in clinical
practice must await validation by additional clinical and laboratory
experience. The correct interpretation of drug test results is predicated
on knowing the performance characteristics of the analytical method, route
of administration, and pharmacokinetics of the drug. All questionable
positive results need confirmation testing to verify true positivity.
[References: 100]
P. Kintz, R.
Brenneisen, P. Bundeli and P. Mangin (1997). "Sweat testing for heroin and
metabolites in a heroin maintenance program." Clinical Chemistry
43(5): 736-9.
Recent
advances in sensitive analytical techniques have enabled the analysis of
drugs in unconventional biological materials such as sweat. In a study
conducted during a heroin maintenance program, 14 subjects had sweat
patches applied, then received intravenously two or three doses of heroin
hydrochloride ranging from 80 to 1000 mg/day. The sweat patch was applied
10 min before the first dosage and removed approximately 24 h later,
minutes before the next dosage. Absorbent pads were stored at -20 degrees
C in plastic tubes until analysis. The target drugs were extracted in 5 mL
of acetonitrile in the presence of 100 ng each of heroin-d9,
6-acetylmorphine-d3, and morphine-d3. After agitation for 30 min, the
acetonitrile solution was divided into two portions: 2 mL for heroin
testing and the remainder for testing for the other compounds. After
evaporation, the residue of the first portion was reconstituted in 35
microL of acetonitrile; the second was derivatized by silylation with 40
microL of N,O-bis(trimethylsilyl)trifluoroacetamide containing 10 mL/L
trimethylchlorosilane. Drugs were analyzed by GC-MS in electron impact
mode. Concentrations (nanograms per patch) ranged from 2.1 to 96.3 for
heroin, 0 to 24.6 for 6-acetylmorphine, and 0 to 11.2 morphine. Except in
one case, heroin was the major drug present in sweat, followed by
6-acetylmorphine and morphine. We observed no correlation between the
doses of heroin administered and the concentrations of heroin measured in
sweat.
R. Fogerson, D.
Schoendorfer, J. Fay and V. Spiehler (1997). "Qualitative detection of
opiates in sweat by EIA and GC-MS.[comment]." Journal of Analytical
Toxicology 21(6): 451-8.
Sweat
was collected with the PharmChek sweat patch, and drugs were eluted from
the collection pad of the patch. A solid-phase enzyme immunoassay (EIA)
using microtiter plates was modified for the analysis of opiates in sweat.
After opiate administration, sweat contains primarily parent opiate
(heroin, codeine) and lipophilic metabolites (6-monoacetylmorphine
[6-MAM]). The immunoassay was determined to have a cross-reactivity with
codeine of 588%, with hydrocodone of 143%, with diacetylmorphine of 28%,
and with 6-MAM of 30% relative to 100% for the morphine calibrators. The
optimum cutoff concentration for this modified assay was determined by
receiver operator characteristic analysis using 215 patches from 95
subjects to be 10 ng/mL morphine equivalents. At this cutoff concentration
the assay had a diagnostic sensitivity of 86.9% and a diagnostic
specificity of 92.8% versus gas chromatography-mass spectrometry (GC-MS),
which was the reference method. The positive predictive value at a
prevalence of 50% was 86%. The intra-assay precision at 10 ng/mL was 7.8%,
and the interassay coefficient of variation (CV) was 39%. Analysis of
spiked patches around the cutoff gave a percent positive threshold of
approximately 50% between 10 and 15 ng/mL and a 95% confidence level for a
positive result by the EIA between 20 and 25 ng/mL. Eighteen possible
adulterants that could be injected into or under the patch were studied.
Two (tile cleaner and detergent) can cause false-positive responses in the
immunoassay. Two adulterants reduced response to spiked drug (Visine eye
drops and Ben Gay ointment), which could cause a false-negative response.
All results were confirmed by GC-MS. The clinical sensitivity and
specificity for detecting drug use by analyzing sweat collected from human
subjects following known doses of codeine (0, 30, and 60 mg orally) or
heroin (20 mg intravenously) were 76 and 100%, respectively.
P. Kintz, C.
Sengler, V. Cirimele and P. Mangin (1997). "Evidence of crack use by
anhydroecgonine methylester identification." Human & Experimental
Toxicology 16(2): 123-7.
A
method using gas chromatography coupled to mass spectrometry for the
determination of cocaine (COC) pyrolysis product, anhydroecgonine
methylester (AEME), in plasma, saliva, urine, sweat and hair is described.
The same procedure allows the simultaneous determination of COC,
benzoylecgonine (BZE), ecgonine methylester (EME) and cocaethylene (CE).
After suitable sample preparation (desorption of the sweat patch, acid
hydrolysis of the hair) the target drugs were extracted using a 3-steps
liquid-liquid extraction (pH 8.4) in presence of deuterated internal
standards in chloroform-isopropanol-n-heptane (50 : 17 : 33, v/v).
Derivatization was achieved using BSTFA+1% TMCS. Ions for AEME monitoring
were m/z 82, 166, 152 and 181. Artifact formation from COC or EME of AEME
during the injection was less than 0.5%. AEME was never detected in blood
sample although the corresponding urine tested positive. Urine
concentrations, in about 90 positive AEME samples, were in the range 5 to
1477 ng/ml. In one case of crack overdose, AEME in sweat was 53 ng/patch
with a COC concentration of 1231 ng/patch. AEME in saliva ranged from 5 to
18 ng/ml in the same case. Finally, AEME was identified in 32 hair
specimens of crack abusers including fetal hair, with concentrations in
the range 0.20 to 21.56 ng/mg. These results suggest that AEME can be a
useful marker for the detection of COC smoking in clinical and forensic
cases.
D. A. Kidwell, M.
A. Blanco and F. P. Smith (1997). "Cocaine detection in a university
population by hair analysis and skin swab testing." Forensic Science
International 84(1-3): 75-86.
The
ability to detect cocaine use/exposure by either hair or sweat analysis
was compared in a random population of adults at a major US university.
Sweat was obtained by wiping the forehead with a cosmetic puff containing
isopropanol. Using cut-off levels for sweat of 2.2 ng cocaine/wipe and of
hair of 0.05 ng cocaine/mg hair, sweat detected two times more cocaine
use/exposure than did hair. Sweat analysis detected a use rate of 12%
compared to a 6% rate by hair analysis, both greater than the 2% that
would be expected in this population. The high rate of detection was
surprising and suggests that use of, if not exposure to, cocaine is
underreported. Controlled experiments showed that cocaine could remain on
the skin for about 3 days after external exposure. At the current state of
knowledge, sweat appears to measure both use and exposure. Nevertheless,
sweat testing could be used in several scenarios (such as roadside driving
while intoxicated) where the case of collection and testing of sweat could
outweigh the passive exposure considerations. Cocaine concentrations in
skin swabs > 15 ng/swab would appear to indicate recent use/exposure.
G. Skopp, L.
Potsch and M. R. Moeller (1997). "On cosmetically treated hair--aspects
and pitfalls of interpretation." Forensic Science International
84(1-3): 43-52.
Popular hair cosmetic treatments like bleaching or permanent waving were
found to affect the stability of incorporated drugs and to cause
alterations of the fibers at an ultrastructural level. This may result in
a partial or complete loss of drug substances, depending on the particular
drug molecule and on its concentration prior to the cosmetic treatment.
Moreover, from literature, there is some evidence that drug molecules are
not only incorporated into the growing fiber by passive diffusion from
blood into the matrix cells and melanocytes, but that the substances enter
the hair also via perspiration such as sweat and sebum. Since permed and
bleached hair shows an enhanced sorption capacity, the risk of false
positives or an unusually high drug concentration in cosmetically treated
hair was under investigation. Virgin, permed, mildly as well as severely
bleached tresses were exposed to artificial sweat or sebum containing
cocaine, benzoylecgonine, 6-acetylmorphine, morphine and codeine (500 ng/g).
Except codeine, the concentrations measured by GC/MS were very small and
quite close to the detection limit indicating a minor importance of drug
uptake into hair fiber from the endogenous-exogenous shunt via sebum or
sweat. From the results it is concluded that an increased risk of false
positive results in hair analysis on bleached and permanent waved hair
fibers does exist, but is not particularly severe.
V. Spiehler, J.
Fay, R. Fogerson, D. Schoendorfer and R. S. Niedbala (1996). "Enzyme
immunoassay validation for qualitative detection of cocaine in sweat."
Clinical Chemistry 42(1): 34-8.
A
solid-phase enzyme immunoassay (EIA) involving microtiter plates was
modified for analysis of cocaine in sweat. Sweat was collected with the
PharmChek sweat patch and drugs were eluted from the collection pad of the
patch. The sweat contained primarily parent cocaine. The assay was
determined to have cross-reactivity for cocaine of 102% relative to 100%
for the benzoylecgonine (BE) calibrators and for cocaethylene of 148%. The
optimum cutoff concentration for this modified assay, determined by
receiver-operating characteristic curve analysis, was 10 micrograms/L
cocaine or BE equivalents. At this concentration the assay had 94.5%
sensitivity and 99.1% specificity vs gas chromatography-mass spectrometry
(GC-MS) as an acceptable indicator of the true clinical state. The
positive predictive value at a prevalence of 50% was 99%. Threshold
analysis for positives suggested that the 95% confidence interval for a
positive result by the EIA was between 12.5 and 15 micrograms/L and that
quality-control samples at 5 and 15 micrograms/L could be run with each
batch to certify the precision around the cutoff. All positive samples
must be confirmed by GC-MS. The sensitivity and specificity of the overall
analysis system (immunoassay screen and GC-MS confirmation) was 86% and
97%, with known cocaine dosing of volunteers as the acceptable indicator
of the true clinical state.
P. Kintz (1996).
"Drug testing in addicts: a comparison between urine, sweat, and hair."
Therapeutic Drug Monitoring 18(4): 450-5.
The
standard in drug testing is the immunoassay screen, followed by a gas
chromatography/mass spectrometry confirmation conducted on a urine sample.
Recently sweat and hair analyses were proposed for identifying drug
abusers. Specimens can be collected under close supervision without
embarrassment and are not subject to evasive maneuvers. In contrast with
urine, hair analysis has a wide window of detection, ranging from months
to years, and provides information concerning the severity and pattern of
an individual's drug abuse. Testing individuals for illicit drugs with
sweat patches worn continually would provide effective coverage for a
week. Studies conducted in a detoxification center have shown that hair
analysis is more sensitive for detecting illicit drug use than is urine
screening. My experience in drug testing is discussed in the light of the
existing literature.
S. Balabanova, E.
Schneider, R. Wepler, B. Hermann, H. J. Boschek and H. Scheitler (1992).
"[Significance of drug determination in pilocarpine sweat for detection of
past drug abuse]." Beitrage zur Gerichtlichen Medizin. 50:
111-5.
The presence of cocaine, morphine and
methadone in sweat samples obtained after stimulation of the eccrine sweat
glands, from drugs users after six drugs-free days, was investigated. The
stimulation of the sweat elimination was proved using
pilocarpine-iontophoresis every hour for 7 hours. The drugs concentrations
were determined by radioimmunoassay. Consequently, the values measured
represent the sum of the drug and its metabolites. Measurable levels of
cocaine, morphine and methadone were obtained after the third stimulation
of the glands.
|
