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. (See table 1.)

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, sug-

gests 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 (see table

2) 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 marijuanapositive

hair samples (out of a total of

503 hair assays and 690 urine assays—

see table 3.) 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 marijuanapositive

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.