Hair Analysis as a Drug Detector
By Tom Mieczkowski, Ph.D.
Series: NIJ Research in Brief Published: October 1995 Tom Mieczkowski,
Ph.D., is Associate Professor of Criminal Justice in the Department of
Criminology, University of South Florida.
Copies of the unpublished full report prepared for NIJ grant
#92-IJ-CX-K010, “Hair Assays for Drugs of Abuse in a Probation
Population: Implementation of a Pilot Study in a Correctional Field
Setting,” by Tom Mieczkowski, Ph.D., Richard A. Newel, Gail Allison, and
Shirley Coletti, are available on interlibrary loan or as photocopies for
a minimal fee. Call NCJRS, 800-851-3420; ask for NCJ 152420.
Issues and Findings
Discussed in this Brief: An NIJ-sponsored study of the viability and
effectiveness of testing hair samples for drug use among probationers,
which was conducted with the assistance of correctional officers from
divisions of the Florida Department of Corrections Probation Field
Services.
Key issues: Because urine testing of drug offenders is known to be
particularly burdensome, a pilot study was developed to determine whether
hair assays, which are noninvasive and have a larger window of detection,
could be more effective. Over a 6-month period, volunteer probationers
were tested for a variety of substances. Researchers also questioned the
field officers about their opinions as to the usefulness of the
testing.
Key findings: Researchers used both methods to test for cocaine,
opiates, marijuana, and other drugs. Among their findings:
- Hair analysis is a better indicator of cocaine use over an extended
timeframe and can more accurately identify a chronic drug user. Urine
analysis, on the other hand, is better able to measure short-term
exposure to cocaine. - Urine analysis seems to be a better way to detect opiates,
particularly the presence of codeine. Hair assays are designed to
detect morphine-based compounds. - Both hair and urine tests appear to have equal effect in detecting
the presence of marijuana. - Hair and urine testing can complement one another because of their
capacity to expose different patterns of drug use. - The field officers agreed that hair testing for drugs can be
beneficial in their efforts to manage their cases and to track drug use
over a longer time period. Most of the officers agreed that gathering
hair for tests was less difficult than collecting urine samples.
Target audience: Probation/parole officers, law enforcement officials,
policymakers, and researchers.
Testing hair samples for drugs of abuse may offer certain advantages
over urine testing methodologies. Drugs and drug metabolites remain
sequestered in the hair shaft indefinitely, thus providing detection
during a much larger “window” (approximately 60 days of use can be seen
in one inch of hair) than drug levels in urine, which decrease rapidly,
through excretion, over a short period of time (generally within 48 to 72
hours). From an operational standpoint, the collection, transportation,
preservation, and storage of nonseptic and inert hair samples are simple
processes and relatively noninvasive when compared to those associated
with collecting observed urine specimens.
An NIJ-sponsored pilot study assessed the feasibility and
effectiveness of doing hair assays in a probationary field setting and
the attitude of probation officers regarding hair testing.
Recruitment and retention of probationers
Twenty-two correctional officers from divisions of the Florida
Department of Corrections Probation Field Services voluntarily
participated in this study. Officer-volunteers were asked to solicit from
each of their caseloads 8-10 volunteers who were currently undergoing at
least monthly urine testing. A simple hair collection procedure was
incorporated into the officers’ appointment routine, but no information
on the outcome of the hair assays was used in any aspect of case
management. At each appointment the officers collected a urine specimen
and a hair specimen from the probationer.
Of the 152 volunteer probationers initially recruited for the project,
91 participated for the entire 6-month collection period, and complete
specimens were collected for 89. The study cohort was predominantly male
(72 men versus 19 women) and white (87 Caucasians, 3 African Americans,
and 1 Hispanic were represented). Researchers attributed the low number
of African- American participants to demographics of Pinellas and Pasco
county regions (only about 7 percent of the population in these counties
is African-American), as well as to the fact that young African-American
males were likely to have extremely short head hair; the project did not
attempt to retrieve body hair samples.
Hair and urine specimens were conjointly analyzed for cocaine,
opiates, cannabinoids, PCP, and methadone. Cutoff values for hair
analysis (2 ng/10 mg for cocaine and heroin, and .05 ng/10 mg for
cannabinoids) were recommended by the testing laboratory, and
NIDA-established cutoffs (300 ml/150 for cocaine, 300 ml/300 for heroin,
and 100 ml/15 for marijuana) were used for urinalysis.
Outcomes of hair and urine assays
Complete sets of hair and urine specimens were obtained from 89
probationers. Of these, 36 were negative on both hair and urine assays,
and 33 were positive on both hair and urine assays. In 12 cases,
probationers tested negative on the urine assays and positive on the hair
assays; in 8 cases, probationers tested positive on the urine assays and
negative on the hair assays. Of the 89 complete cases, 53 had a positive
assay on at least one hair or urine sample. A slightly higher number of
drug-positive cases was detected in the hair assays (45) than in the
urine assays (41).
Cocaine. The main criteria for measuring effectiveness of cocaine
detection in this study were the ability of hair analysis to identify
periodic or chronic exposure to the drug and the ability of urinalysis to
measure acute or short-term exposure. Of the 89 completed cases, there
were none in which a probationer’s urine specimen tested cocaine-positive
and hair specimen tested cocaine-negative. This pattern, according to the
study, suggests that hair analysis is effective in identifying periodic
cocaine exposure.
Opiates. The research team was interested in evaluating the detection
of chronic opiate use by analysis of hair and comparing those findings to
the outcomes of urinalysis and any self-reports for opiates. Two problems
arose, however. The major limitation was that there were very few
opiate-positive cases within the sample. Secondly, the hair assay for
opiates is somewhat more limited than urinalysis; the hair assay was not
designed to detect codeine while the urine assay did detect codeine.
Thus, the two assays were not comparable.
Opiates were much less prevalent than cocaine or marijuana. Of all
subjects in the study, only 11 had one or more opiate-positive hair
samples, and 14 had opiate-positive urine samples. These findings include
five cases in which urine samples were positive for opiates but the
corresponding hair assays were opiate-negative. In one of these five
cases, three opiates were detected in urine samples, but none were
detected in hair. In the four remaining cases, the urine-positive,
hair-negative outcomes appeared at either the first or the fifth or sixth
urine samples. Several interpretations of these data are possible. The
hair assay may be less effective for opiates than for other drugs.
Alternatively, the urine assay may be detecting the presence of codeine
from abused medicinals, while the hair assays (which detect
morphine-based compounds) show a negative because the person has not
consumed heroin or morphine.
Possibly the opiates were near or under the limit of detection in the
hair assays; or, in the cases where the urine-positive result occurred at
the end of the study (i.e., in the fifth or sixth sample), the hair may
not have had sufficient time to emerge above the scalp (i.e., the sample
was taken too early relative to the time the drug was consumed).
Marijuana. Marijuana was the most prevalent drug detected within the
sample group by either type of assay. When considering all cases
(completed or not), 53 marijuana cases accounted for a total of 149
marijuana-positive hair samples (out of a total of 503 hair assays and
690 urine assays. The most likely outcome for any completed case, over
the full 6-month period, was that the hair and urine assays for marijuana
would be concordant, though not necessarily for the same timeframe. For
example, of the 89 completed cases, in 33 at least 1 positive assay for a
drug occurred in at least 1 specimen (either hair, urine, or both). Of
those 33 cases, 24 had a marijuana-positive assay. Of those 24, 16 had a
marijuana-positive assay in hair only; 3 had a marijuana-positive assay
in urine only. This suggests that, generally speaking, the hair assay for
marijuana is about equal in effect to the urine assay. It does not show
the enhanced detection capability that appears to be true for cocaine
assays, but the researchers believe that this result is to be expected.
Marijuana may be detected in urine for a relatively long period of time
(compared to cocaine), and one would not expect as dramatic a departure
in detection rates for a drug with long urine retention times.
Other drugs. There were no detections of PCP or methadone in the
sample group.
Participant opinions and experiences
Field officers. Participating officers varied widely in their
estimates of the degree of probationer drug involvement among their
cases; the mean value of estimated drug-user cases was 38.8 percent (s.d.
= 18.6 percent). This was quite accurate since 40.4 percent of the
participating probationers had one or more positive assays (either hair,
urine, or both). If urinalysis alone were used, only 9.8 percent of these
probationers would have been detected as positive. Nearly all officers
supported the concept and practice of probationary drug testing, when
properly conducted. Most officers said that collecting hair samples was
less burdensome than collecting urine specimens. The researchers observed
that officers were readily able to collect, package, and transport hair
samples and to obtain probationers’ cooperation.
Many officers perceived hair testing as a way to manage their cases
more effectively. For example, their ability to sort a series of
drug-positive clients into rank order categories such as “heavily,”
“moderately,” or “casually” exposed would be enhanced, as would their
capability to track drug use retrospectively (especially cocaine) over a
longer timeframe.
Probationers. Probationers ranged in age from 17 to 53 years, with a
mean age of 29.63 years (s.d. = 7.81) and a median age of 29 years. Drug
possession was the single most frequent offense charged against this
group, with drug sales, assault, and larceny following closely
behind.
Probationers were asked about their lifetime drug habits. When asked
about cocaine, 45.5 percent admitted some lifetime use; 35.5 percent
admitted monthly use; and 28.8 percent admitted weekly or greater use.
Regarding marijuana, 71.1 percent admitted some lifetime use.
Implications
The researchers suggest that hair assay technology could usefully be
combined with urine testing in probation population management. For
example, hair testing could be used as an initial screen for the
identification of long patterns of drug use, especially cocaine.
Individuals with indications of severe drug involvement could be placed
on appropriate treatment and monitoring, utilizing both urine and hair
testing, for example. Those who indicate a low level of exposure and
whose claims are consistent with assay results might be assigned to a
less intensive protocol involving, for example, hair testing every 60
days supplemented by a random urine testing requirement. Under such a
system, the data of this project indicate that the detection of users
will be enhanced and will conform more closely to the self-reported
levels of use and the probation officers’ expectations of use.
Findings and conclusions of the research reported here are those of
the authors and do not necessarily reflect the official position or
policies of the U.S. Department of Justice.
The National Institute of Justice is a component of the Office of
Justice Programs, which also includes the Bureau of Justice Assistance,
Bureau of Justice Statistics, Office of Juvenile Justice and Delinquency
Prevention, and the Office for Victims of Crime.
