### C

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# ABOUT THE LAW ENFORCEMENT AND CORRECTIONS

**STANDARDS AND TESTING PROGRAM**

The Law Enforcement and Corrections Standards and Testing Program is
sponsored by the Office of Science and Technology of the National
Institute of Justice (NIJ), U.S. Department of Justice. The program
responds to the mandate of the Justice System Improvement Act of 1979,
which directed NIJ to encourage research and development to improve the
criminal justice system and to disseminate the results to Federal,
State, and local agencies.

The Law Enforcement and Corrections Standards and Testing Program is an
applied research effort that determines the technological needs of
justice system agencies, sets minimum performance standards for specific
devices, tests commercially available equipment against those standards,
and disseminates the standards and the test results to criminal justice
agencies nationally and internationally.

The program operates through:

The *Law Enforcement and Corrections Technology Advisory Council*
(LECTAC), consisting of nationally recognized criminal justice
practitioners from Federal, State, and local agencies, which assesses
technological needs and sets priorities for research programs and items
to be evaluated and tested.

The *Office of Law Enforcement Standards* (OLES) at the National
Institute of Standards and Technology, which develops voluntary national
performance standards for compliance testing to ensure that individual
items of equipment are suitable for use by criminal justice agencies.
The standards are based upon laboratory testing and evaluation of
representative samples of each item of equipment to determine the key
attributes, develop test methods, and establish minimum performance
requirements for each essential attribute. In addition to the highly
technical standards, OLES also produces technical reports and user
guidelines that explain in nontechnical terms the capabilities of
available equipment.

The *National Law Enforcement and Corrections Technology Center
(NLECTC),* operated by a grantee, which supervises a national compliance
testing program conducted by independent laboratories. The standards
developed by OLES serve as performance benchmarks against which
commercial equipment is measured. The facilities, personnel, and testing
capabilities of the independent laboratories are evaluated by OLES prior
to testing each item of equipment, and OLES helps the NLECTC staff
review and analyze data. Test results are published in Equipment
Performance Reports designed to help justice system procurement
officials make informed purchasing decisions.

Publications are available at no charge through the National Law
Enforcement and Corrections Technology Center. Some documents are also
available online through the Internet/World Wide Web. To request a
document or additional information, call 800--248--2742 or
301--519--5060, or write:

> National Law Enforcement and Corrections Technology Center
>
> P.O. Box 1160
>
> Rockville, MD 20849--1160
>
> E-Mail: *asknlectc@nlectc.org*
>
> World Wide Web address: *http://www.nlectc.org*

This document is not intended to create, does not create, and may not be
relied upon to create any rights, substantive or procedural, enforceable
at law by any party in any matter civil or criminal.

Opinions or points of view expressed in this document represent a
consensus of the authors and do not necessarily represent the official
position or policies of the U.S. Department of Justice. The products and
manufacturers discussed in this document are presented for informational
purposes only and do not constitute product approval or endorsement by
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,
  the Bureau of Justice Statistics, the Office of Juvenile Justice and
  Delinquency Prevention, and the Office for Victims of Crime.

  -----------------------------------------------------------------------

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#   {#section .unnumbered}

# ACKNOWLEDGMENTS

# 

# 

# The technical effort to develop this report was conducted under Interagency Agreement 94--IJ--R--004, Project No. 99--002IA.

This research was done under Grant Award Number 60NANB9D0050 from the
National Institute of Standards and Technology (NIST) to the Institute
of Social Analysis (ISA).

This report was prepared by the Office of Law Enforcement Standards
(OLES) of NIST under the direction of Alim A. Fatah, Program Manager for
Chemical Systems and Materials, and

Kathleen M. Higgins, Director of OLES.

# 

**FOREWORD**

The Office of Law Enforcement Standards (OLES) of the National Institute
of Standards and Technology (NIST) furnishes technical support to the
National Institute of Justice (NIJ) program to strengthen law
enforcement and criminal justice in the United States. OLES's function
is to conduct research that will assist law enforcement and criminal
justice agencies in the selection and procurement of quality equipment.

OLES is: (1) Subjecting existing equipment to laboratory testing and
evaluation, and (2) conducting research leading to the development of
several series of documents, including national standards, user guides,
and technical reports.

This document covers research conducted by OLES under the sponsorship of
the National Institute of Justice. Additional reports as well as other
documents are being issued under the OLES program in the areas of
protective clothing and equipment, communications systems, emergency
equipment, investigative aids, security systems, vehicles, weapons, and
analytical techniques and standard reference materials used by the
forensic community.

Technical comments and suggestions concerning this report are invited
from all interested parties. They may be addressed to the Office of Law
Enforcement Standards, National Institute of Standards and Technology,
100 Bureau Drive, Stop 8102, Gaithersburg, MD 20899**--**8102.

> Kathleen M. Higgins, Director
>
> Office of Law Enforcement Standards

CONTENTS

Foreword iii

COMMONLY USED SYMBOLS AND ABBREVIATIONS vi

1\. BACKGROUND 2

1.  General 2

2.  Drug Testing in the Criminal Justice System 2

3.  Sweat Testing 3

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2.  METHODOLOGY 4

2.1 Introduction 4

2.2 Site Preparations 5

2.3 Selection of a Collection Device 5

2.4 Modification of the Collection Device 6

5.  Pilot Study Procedures 7

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3.  RESULTS 10

3.1 Collection of Liquid Perspiration: Volumes and Rates 10

2.  Participant Perceptions of Collection Methods 12

3.  Methods Development: Drug Screening 14

> 3.4 Methods Development: MS Confirmations 15
>
> 3.5 Results: Biological Specimens 17

3.  DISCUSSION 27

4.  CONCLUSIONS 28

6\. REFERENCES 29

FIGURES

Figure 1. Liquid perspiration volumes collected 11

Figure 2. Liquid perspiration collection rates 12

Figure 3. Session perceptions 13

TABLES

Table 1. Administration of standard and modified LP collectors 8

Table 2. Screening cutoff concentrations 14

Table 3. Confirmation methods 16

Table 4. Specimen summary 18

Table 5. Urine drug test results 19

Table 6. Sweat patch drug test results 21

Table 7. Liquid perspiration results - MS 23

Table 8. Liquid perspiration screen only drug test results 24

Table 9. Summary of positive test results 26

COMMONLY USED SYMBOLS AND ABBREVIATIONS

  ------ --------------- ----- -------- ------------- -- ---- ------ --------------
  A      ampere                H        henry                 nm     nanometer

  AC     alternating           H        hour                  No.    number
         current                                                     

  AM     amplitude             Hf       high                  o.d.   outside
         modulation                     frequency                    diameter

  Cd     candela               Hz       hertz                 Ω      ohm

  Cm     centimeter            i.d.     inside                p\.    page
                                        diameter                     

  CP     chemically pure       In       inch                  Pa     pascal

  c/s    cycle per             IR       infrared              pe     probable error
         second                                                      

  d      day                   J        joule                 pp.    pages

  dB     decibel               L        lambert               ppm    parts per
                                                                     million

  DC     direct current        L        liter                 qt     quart

  °C     degree Celsius        Lb       pound                 rad    radian

  °F     degree                Lbf      pound‑force           rf     radio
         Fahrenheit                                                  frequency

  diam   diameter              lbfin   Pound‑force           rh     relative
                                        inch                         humidity

  emf    electromotive         Lm       Lumen                 s      second
         force                                                       

  eq     equation              Ln       Logarithm             SD     standard
                                        (base e)                     deviation

  F      farad                 Log      Logarithm             sec.   section
                                        (base 10)                    

  fc     footcandle            M        Molar                 SWR    standing wave
                                                                     ratio

  fig.   figure                M        Meter                 uhf    ultrahigh
                                                                     frequency

  FM     frequency             min.     Minute                UV     ultraviolet
         modulation                                                  

  ft     foot                  mm       Millimeter            V      volt

  ft/s   foot per second       mph      Mile per hour         vhf    very high
                                                                     frequency

  *g*    acceleration          m/s      Meter per             W      watt
                                        second                       

  g      gram                  N        Newton                λ      wavelength

  gr     grain                 Nm      Newton meter          wt     weight
  ------ --------------- ----- -------- ------------- -- ---- ------ --------------

area=unit^2^ (e.g., ft^2^, in^2^, etc.); volume=unit^3^ (e.g., ft^3^,
m^3^, etc.)

PREFIXES COMMON CONVERSIONS

(See ASTM E380)

  ---- ----------- ---- -------------- ----------------- ------------------
  d    deci        da   deka (10)      0.30480 m =1 ft   4.448222 N = 1 lbf
       (10^-1^)                                          

  c    centi       h    hecto (10^2^)  25.4 mm = 1 in    1.355818 J = 1
       (10^-2^)                                          ftlbf

  m    milli       k    kilo (10^3^)   0.4535924 kg = 1  0.1129848 Nm = 1
       (10^-3^)                        lb                lbfin

  µ    micro       M    mega (10^6^)   0.06479891 g = 1  14.59390 N/m = 1
       (10^-6^)                        gr                lbf/ft

  n    nano        G    giga (10^9^)   0.9463529 L = 1   6894.757 Pa = 1
       (10^-9^)                        qt                lbf/in^2^

  p    pico        T    tera (10^12^)  3600000 J = 1     1.609344 km/h = 1
       (10^-12^)                       kWhr             mph
  ---- ----------- ---- -------------- ----------------- ------------------

Temperature: T~°C~ = (T~°F~-32)×5/9

Temperature: T~°F~ = (T~°C~×9/5)+32

**An Evaluation of Innovative Sweat-Based Drug Testing**

**Techniques for Use in Criminal Justice**

**Drug Testing**

Dennis J. Crouch, University of Utah, Center for Human Toxicology, Salt
Lake City, UT 84112; and

Dr. Royer F. Cook, Dr. James V. Trudeau, and David C. Dove, Institute
for Social Analysis,

201 North Union Street, Alexandria, VA 22314.

This Interim Report describes progress to date of the project, "An
Evaluation of Innovative Sweat-Based Drug Testing Techniques for Use in
Criminal Justice Drug Testing." This three-year project is a
collaborative effort between the Institute for Social Analysis (ISA),
the prime contractor, and the University of Utah's Center for Human
Toxicology (CHT), the sub-contractor.

This project is assessing the feasibility of adapting a device
originally designed to collect liquid perspiration from infants to test
for cystic fibrosis (the Macroduct) for use in criminal justice settings
to test for drug use (as an alternative to urinalysis and the sweat
patch). The primary focus of this report is a pilot study that compared
liquid perspiration test results to urinalysis and sweat patch results,
and obtained participant perceptions of the different collection
methods. The pilot study was conducted at the Pre-Trial Services Agency
(PSA) in Washington, DC, in April 2000.

> ISA and CHT would like to acknowledge Wayne Barlow, President;
>
> Kent Thomas, Business Manager; Lewis Webster, Senior Scientist; and
>
> Dennis Briscoe, Chief Engineer from Wescor, Inc., for their assistance
> in planning the project, modifying the collector, and their scientific
> consultation. We would also like to acknowledge the cooperation and
> support of
>
> Mr. Jerome Robinson and his staff from the PSA. Without the support,
> cooperation and consultation provided by Wescor, Inc., and PSA, this
> pilot study could not have been successfully completed.

**1. BACKGROUND**

**1.1 General**

After a brief overview of the project, this section describes the
rationale for the project and reviews pertinent research on drug testing
in criminal justice settings.

The project began on May 24, 1999, and will be conducted over a period
of three years. Project objectives are as follows:

-   Modify and test innovative, less invasive liquid perspiration (LP)
    collection devices.[^1]

-   Adapt drug screening kits for use in analyzing LP samples and
    develop drug confirmation methods.

-   Assess the validity and utility of the LP collection device as a
    method of drug testing with criminal justice populations.

The project is being conducted in conjunction with the Pre-Trial
Services Agency in Washington, DC. This agency, a pioneer in the
applications of drug testing to criminal populations, currently drug
tests approximately 155 000 urine specimens annually using an in-house
high-speed auto-analyzer. They are an ideal field study site because
they test several hundred arrestees *daily*, the majority of whom test
positive for one or more drugs; and they have previously participated in
field test trials of innovative drug tests.

1.2 Drug Testing in the Criminal Justice System

Drug testing is now widely used throughout the criminal justice system.
Major uses include: (1) the Arrestee Drug Abuse Monitoring (ADAM) system
(an expansion and refinement of the Drug Use Forecasting ---- DUF
program), by which samples of arrestees in sites around the country are
tested to estimate drug use prevalence in the arrestee population (NIJ,
1996)[^2]; (2) pretrial drug testing, used to make decisions about
probation or pretrial release, and to supervise drug-involved defendants
more closely (Visher, 1992); (3) post-adjudication testing of drug
offenders by probation and parole departments (Turner, et al., 1994);
and (4) testing of law enforcement personnel (Reaves, 1992). In addition
to these major programs, drug testing is also a significant element in
drug courts (Goldkemp and Weiland, 1993) and in programs designed to
assess drug use among juvenile detainees (Dembo et al., 1990). Moreover,
data on the effectiveness of drug testing is sufficiently supportive
that testing is likely to expand throughout the criminal justice system
(Mieczkowski and Lersch, 1997).

Currently, most drug testing in criminal justice is based on analysis of
urine specimens by immunoassay (screening) and gas chromatography/mass
spectrometry (GC/MS) (confirmation). Although recently alternative
testing techniques such as hair analysis and on-site kits have become
more common (NIJ, 1996), the laboratory-based methods remain the "gold
standard" by which other methods are assessed. However, despite its
advantages, urine testing involves collection methods that are invasive
---- often discomfiting to donor and collector alike ---- and which
typically require burdensome facilities and procedures. It would be
highly desirable to develop a practical, cost-effective method of drug
testing that is as accurate as urine testing, but less invasive. Among
the alternative technologies that are in various stages of development
are hair analysis, perspiration analysis, and saliva analysis. Hair
analysis is perhaps the most advanced of these technologies; several
commercial laboratories are now performing hair analysis, and
researchers have begun to test its efficacy in criminal justice settings
(Mieczkowski, 1993). However, because of potential problems with
contamination and hair color bias, the accuracy and utility of hair
analysis remain in question, (Cook et al., 1996; and NIJ, 1996). In
principle, the analysis of other body fluids ---- perspiration and
saliva ---- should offer the most promising noninvasive means of drug
testing.

Several devices are now available for saliva testing; however, little is
known about the utility of these devices or how drugs and their
metabolites are transferred from blood to saliva. In addition,
immediately after smoking or orally ingesting a drug, the oral cavity
may be contaminated by the drug leading to falsely elevated saliva-drug
concentrations. Also, drug concentrations in saliva appear to vary by
collection method (O'Neal, et al., 2000). Therefore, among the less
invasive methods, sweat testing appears the most promising. Moreover,
new liquid perspiration collection devices appear to be promising
noninvasive means of drug testing. These techniques are discussed below.

1.3 Sweat Testing

Sweat collection devices have been approved for clinical applications
and for drugs of abuse testing. Amphetamine and methamphetamine, heroin,
morphine, methadone, and phencyclidine have all been detected in sweat
(Baer and Booher, 1994). Sweat may be collected on tamper proof
absorbent patches. The patches are applied to the subject with a simple
adhesive and may be worn for extended periods of time. While the patch
is worn, sweat is absorbed and drug(s) and their metabolite(s) are
deposited on it. Several studies have been performed to evaluate the
efficacy of detecting drug use with sweat patch testing (Burns, 1995;
Fogerson, et al., 1997; and Kintz, 1996). These studies have shown that
the patches are particularly useful in criminal justice settings where
constant surveillance through use of the sweat patch has detected drug
use that was not detected using discrete urinalysis tests. The patches
are also potentially useful in drug treatment and parole/probation
programs where abstinence is a measure of treatment compliance and
recidivism can be monitored by having the patient continuously wear a
patch.

A potential problem with sweat testing is that little is known about the
deposition of drugs into sweat, therefore, interpreting the test result
is difficult. In addition, for most drugs, we do not know the minimum
dose that would need to be ingested for the drug to be detected in the
patch. Currently, we cannot predict how long after ingestion drugs of
abuse can be detected in liquid perspiration.

The actual volume of sweat collected by the patch is unknown. This
precludes meaningful (drug/microliter (μL) of LP) quantitative analysis
of drugs detected and limits the interpretative value of the results.
The cost of testing a sweat patch is about the same as urinalysis
testing. However, since drug concentrations are lower and the entire
patch is consumed for a single conformational analysis, repeat testing
and confirmation of multiple drug use are precluded.

The Webster Sweat Collection System was introduced in 1978 (Webster,
1981). This was one of the first systems designed to collect liquid
perspiration. The system is currently designed to harvest LP samples
from infants for use in the early diagnosis of cystic fibrosis (Carter,
1981; and Hammond, 1994). The system consists of pilocarpine discs that
stimulate the sweat glands, a portable power supply that provides a
micro current to induce "iontophoresis", and the LP collection device.
Pilocarpine is a naturally occurring alkaloid that can be extracted from
plants and is used medically to treat glaucoma. In addition, it
stimulates salivation and sweating. In the collection process,
iontophoresis provides a small electrical current (microamps) that
promotes transfer of the ionized pilocarpine through the skin to the
sweat glands stimulating sweat production. There are several potential
advantages to the use of the LP for drug testing in the criminal justice
system. First, sensible sweat is collected. This LP is actively produced
at the time of collection and, therefore, the drug concentrations may be
reflective of blood drug concentrations. The system has Food and Drug
Administration (FDA) approval and has been designed for use with infants
and children. Therefore, it is extremely safe for both the collector and
the donor. The entire system is compact and portable (9.2 cm x 4.5 cm x
15.5 cm, weighs 0.4 kg), and fits into a carrying case no larger than
that used for a laptop computer. Therefore, mobile collections are
feasible and no special facilities are needed. The collector can observe
this entire collection process. The collection device is attached to the
donor\'s forearm and a capillary tube fills with LP by hydrostatic
pressure, thereby ensuring the integrity and identity of the sample. The
collection of LP with this device also has advantages for drug analysis
and interpretation. A significant potential advantage over the sweat
patch is that liquid samples can be analyzed at the site of collection
by laboratory based immunoassay tests or by on-site test kits. The drug
content in liquid samples can also be quantified such that drug test
results can be reported in concentration/μL of LP, improving the
potential for meaningful interpretation.

However, there are also disadvantages to the current version of the
collection device. The price currently exceeds that of patch testing
(\$7/sweat collection vs. \$5/sweat patch). An initial investment of
\$1575 is needed for the power supply. A second disadvantage is that
collection of

50 μL to 60 μL of LP may take 10 min to 15 min ---- although such times
are not that much in excess of the time required for a urine collection.
A third disadvantage is that the device is designed for micro-collection
and the volume of LP collected may limit the type and number of analysis
that can be performed on each specimen. These potential disadvantages
are being addressed in the ongoing project.

**2. METHODOLOGY**

1.  Introduction

Four important aspects of the study methodology are discussed: (1)
preparations, (2) liquid perspiration (LP) collection device selection,
(3) pilot test data collection procedures, and (4) analytical procedures
developed to test the specimens collected during the pilot study.

**2.2 Site Preparations**

Given the developmental nature of this project, initial meetings and
preparation were important for laying the groundwork for the study.
These meetings were critical in finalizing the study design, selecting
and modifying the LP collection device, and planning the pilot study.

2.3 Selection of a Collection Device

Sweat has been extensively studied as a potential diagnostic fluid and
several sweat collection methods are described in the literature. Skin
blotting, skin wipes, capillary tubes, sweat patches, and iontophoresis
have been evaluated (Kidwell et al., 1998). Techniques such as blotting
and skin wipes often rely on occlusive sweat stimulation and collection.
The limb or site of collection is placed in an impermeable environment
such as a plastic bag. Sweat produced by the limb is trapped in the
occlusive bag. Then the skin can be blotted with an absorbent material
or wiped with a specially designed absorbent skin wipe. The quantity of
sweat collected is estimated by comparing the precollection and
post-collection weights of the blotter or wipe. Also, LP can be
harvested from the occlusive bag using a calibrated capillary tube.
Nonocclusive LP collection techniques have also used blotters, skin
wipes and capillary tubes. Sweat is harvested from perspiration that
accumulates on the skin. Different absorbent materials such as gauze and
specially formulated materials have been used for these collections.
Blotting and skin wiping have obvious limitations. Physiological
materials such as sebum, statium corneum, and drugs or chemicals
deposited on the skin may be collected in addition to the LP. Also, the
blotters and skin wipes may be inconsistent in texture and weight,
making collection time-consuming and problematic. Capillary tube
collections also have limitations. The tubes are fragile and must be
graduated by volume. In addition, capillary tube collections rely on
having recognizable LP on the skin surface.

Two sweat collection devices showed promise for use in this project: the
sweat patch and the LP collection device. The patch is FDA approved for
drugs of abuse testing and the LP collection system is FDA approved for
clinical applications such as harvesting sweat for the diagnosis of
cystic fibrosis. The sweat patch is a nonocclusive collection device
that has been developed specifically to harvest perspiration for testing
for drugs of abuse. The patches are approximately

2 in x 3 in and resemble a large adhesive bandage. The patches have an
outer hypoallergenic adhesive layer that is permeable to small
molecules, such as water vapor, and an absorbent pad. Each sweat patch
has a unique identifier for subject tracking and they are tamper
resistant. The patches are attached to the subject's upper arm, chest or
lower back and typically are worn for 7 d to 14 d. While the patch is
worn, drug(s) and their metabolite(s) in the sweat are deposited on the
pad. Several studies have been performed to evaluate the efficacy of
detecting drug use with sweat patch testing (Burns, 1995; Fogerson,
1997; and Kintz, 1996). These studies have shown that the patches are
particularly useful in criminal justice settings. Despite its
advantages, there are several problems with the sweat patch. The volume
of sweat deposited on the patch is not known, therefore, equating a
positive drug test result to dose or time since use is problematic. The
extent of sweating affects the amount of sweat produced by the subject,
the amount of LP collected by the patch, and the amount of drug
deposited on the device. For most drugs, the minimum dose that would
need to be ingested for the drug to be detected on the patch is not
known. Also, it cannot currently be predicted how long (after ingestion)
most drugs can be detected in the sweat patch. A major disadvantage of
sweat patch testing is that (despite the manufacturer's claims) the
patch does not collect insensible perspiration (passive loss of water
vapor through the skin by diffusion). The cost of sweat patch testing is
about the same as urinalysis testing. However, since drug concentrations
are low and the entire patch is consumed for a single conformational
analysis, repeat testing to ensure accuracy and confirmation of multiple
drug use are precluded.

There are also disadvantages to the existing version of the LP
collection system. The major disadvantages are that it collects \<100 μL
of sweat and the collection takes 10 min to

20 min. Although the collection time appears protracted, it is not that
much longer than the time required for a urine collection when custody
and control forms must be completed. The collection volume is a problem
given that drug screening usually requires 10 μL to 50 μL of sample/drug
and MS confirmations typically require at least 1 milliliter (mL) of
sample/drug.

2.4 Modification of the Collection Device

Prior to the pilot study, LP specimens were collected in-house with the
current system (using informed consent). Collections typically took
about 30 min and approximately 60 μL of LP was collected. Some
participants produced less than a complete sample in that time. It was
important to keep the collection time to a length that would be
acceptable by criminal justice practitioners and donors and to maximize
the volume of LP collected, so alternative methods were explored to
increase the rate of LP collection.

Through discussions with the manufacturer, four strategies were
proposed:

1.  Increase the pilocarpine concentration in the induction disks. The
    expected advantage was to decrease the induction time from about 5
    min to perhaps 2.5 min. The expected disadvantages were that there
    is a point of diminishing returns where further induction does not
    result in an increase in LP production, and any time saving would be
    relatively small because the collection takes substantially longer
    than the induction.

2.  Increase the induction voltage, thereby increasing the iontophoresis
    current. The expected advantage was to increase volume of liquid
    perspiration produced through the incorporation of more pilocarpine.
    The expected disadvantage was that there is a critical voltage above
    which further increases will cause discomfort to the subject.

3.  Use more than one collection device. The expected advantage was to
    increase the total LP volume collected. The expected disadvantages
    were that the end-users would need to purchase multiple devices, the
    collection would be more complicated, and participants might be
    reluctant to have multiple devices applied.

4.  Modify the collection device. The expected advantage was to increase
    the skin surface area covered by the device and to increase the
    volume of LP collected per unit time. The disadvantage was that this
    alternative would be more costly in the short term.

We attempted to increase the current and decrease the iontophoresis time
and determine the effect on volume collected, collection time, and
subject discomfort. This resulted in an *increased* collection time,
apparently because less pilocarpine reached the sweat glands. Therefore,
the decision was made to accept a more-costly alternative of modifying
the collector, which seemed to hold the most promise in the long term.
Under subcontract, the manufacturer developed a prototype of the
collector with larger induction and collection surface areas.

**2.5 Pilot Study Procedures**

**2.5.1 Collection Procedures**

Data were collected onsite at a pretrial agency satellite office that
served several hundred clients daily. Data collection occurred during
regular office hours over a 3--week period in April and May 2000. All
arrestees who were required to report to the satellite site for drug
testing were eligible to participate in the project, and a \$20 cash
stipend was provided. Thirty-two arrestees participated in the pilot
study. This sample size was judged sufficient for a preliminary
assessment of the LP collection devices, since it was likely that a
sizable proportion of the specimens collected would be drug-positive.

Written informed consent was obtained from each participant. The
informed consent advised participants that their questionnaire responses
and drug test results would be confidential, and that the test results
would not be used against them in any legal proceeding. Additionally,
researchers and agency staff emphasized that the test results would not
affect participant involvement in their pretrial obligations.

The pilot study involved two sessions of data collection that were one
week apart. During session 1, a sweat patch was applied to each
participant, and he or she provided a urine sample and one or two LP
specimens. In many cases, the participant had just provided a urine
specimen for the pretrial agency; these subjects were not asked to
provide an additional specimen for the study. Instead, an aliquot from
the agency's specimen was obtained. For the other participants, a
trained technician followed the standard agency protocol for urine
collection.

LP collection began with an introduction to the equipment and
procedures, and an opportunity for participants to have any questions or
concerns addressed. Then LP collection using either the standard or
modified collector commenced. Two electrodes with gel-discs containing
pilocarpine nitrate were attached to the participant\'s lower arm. A
low-level current was passed through the pilocarpine disks into the skin
inducing the sweat glands to produce liquid perspiration. The induction
period lasted approximately 5 min. The induction period for the modified
collector, with its larger electrodes and pilocaropine disks, lasted
only 2 min. After the induction period, a standard or modified LP
collection device was placed over the area of the skin where the
induction had occurred. Both collection devices resembled watches, with
a wristband securely attaching the device to the subject's arm. The LP
was collected into a spiral-microbore tube that was part of the
collector. Throughout the process, the research assistant adhered
strictly to the manufacturer\'s instructions for collection.

During the initial session, a sweat patch was applied to the lower
ribcage or upper arm of each participant. Participants were asked to
leave the patch in place for one week and were given instructions for
care. Again, the manufacturer's instructions were followed explicitly.

At the conclusion of the LP collection, both the volume of LP collected
and the collection time were recorded. The LP specimens were then
transferred into glass storage vials and the vials were labeled with a
unique study identification number. After specimen collection and sweat
patch application, participants completed a brief questionnaire about
their recent drug use and their perceptions of the collection
procedures.

The questionnaire asked participants to rate the standard LP collector,
the modified collector, and the urinalysis collection procedure on four
dimensions: discomfort, lengthiness of collection, unpleasant
sensations, and embarrassment. Participants were asked to rate the sweat
patch only at session 2, when the patch was harvested. Ratings were made
on a 3-point scale, with 3 being the most negative response.
Participants were also asked which procedure they liked most and which
they liked least. The final section of the questionnaire asked
participants to report how frequently they had used a variety of illicit
drugs in the last 30 days and how recently they had used the drugs.

Participants were scheduled to return approximately one week later for
session 2 specimen collections. Participants were told that they would
again receive the incentive (\$20) for completing

session 2. Of the 32 session 1 participants, 23 (72 %) returned for
session 2. Each returning participant provided session 2 urine and LP
specimens, the sweat patch was harvested, and they completed a second
drug use and perceptions questionnaire.

Not all subjects provided a full compliment of specimens. Thirty-two
urine specimens were collected at session 1 and 23 specimens were
collected at session 2. Of the 23 participants who participated at
session 2, 20 returned sweat patch specimens (69 % of the total sample).
During the two sessions, the standard LP collector was administered to
all participants at least once. However, the modified LP collector was
only administered to a portion of the subjects due to a limited supply
of the prototype devices. The following table summarizes the LP
collections at sessions 1 and 2. Thirty participants received the
standard collection at session 1 and 15 at session 2. Seventeen
participants received the modified collection at session 1 and 13 at
session 2. Fifteen participants were administered both LP collection
procedures at session 1, and 6 received both at session 2.

***Table 1. Administration of standard and modified LP collectors***

+--------------------+--------------+---------------+-----------------+
| **Device**         | **Session    | **Session 2** | **Total**       |
|                    | 1**          |               |                 |
| **Administered**   |              |               |                 |
+--------------------+--------------+---------------+-----------------+
| Standard alone     | 15           | 9             | 25              |
+--------------------+--------------+---------------+-----------------+
| Modified alone     | 2            | 7             | 9               |
+--------------------+--------------+---------------+-----------------+
| Standard and       | 15           | 6             | 21              |
| modified           |              |               |                 |
+--------------------+--------------+---------------+-----------------+
| Did not            | \--          | 9             | 9               |
| participate        |              |               |                 |
+--------------------+--------------+---------------+-----------------+

**2.5.2 Data and Specimen Handling Procedures**

All specimens were labeled with identification numbers to allow matching
of the survey data with the specimen data. Confidentiality of the survey
data was maintained throughout the analysis. All specimens were treated
as biohazards during collection and handling. The specimens were stored
in secure refrigerated vaults, then cold-packed and shipped via
overnight courier and identified only by study identification number.

2.5.3 Selection and Analytical Methods Development

Potential methods to screen the LP specimens for drugs of abuse were
reviewed. Two promising laboratory-based immunoassays were selected:
enzyme immunoassay (EIA) and radioimmunoassay (RIA). EIA is a
competitive immunoassay in which drug in the urine, or LP, and
enzyme-labeled drug in the test kit compete for a limited antibody. A
substrate is then added to the test mixture, which the enzyme may react,
and the resulting color is read instrumentally (STC, 1996, 1997; and
Fay, 1996). RIA is also a competitive immunoassay technique that detects
drugs in a similar fashion except the radioactivity of the test solution
is measured as an indication of drugs in the sample. Both EIA and RIA
test kits are commercially available.

An assessment of the EIA kits for the analysis of LP was performed.
Known drug-free LP was collected from laboratory volunteers (see above).
These samples were pooled and fortified with drugs of abuse to evaluate
the kits. Two calibration curves were prepared. One contained only
parent drug and the other drug metabolite. These data were used to
establish the limit of detection by EIA, to assess the manufacturers
published procedures, and to determine if there were matrix effects from
LP.

RIA has been used to test a variety of biological specimens (Crouch,
1983; Smith, 1981; Moody, 1992; and Henderson, 1993). Our testing
laboratory has used RIA since the late 1970s to screen urine, serum,
plasma, blood, bloodstains, saliva, and tissue homogenates for drugs of
abuse. The pooled and fortified LP samples discussed above were used to
evaluate the RIA kits for use in testing LP. These data were used to
establish the limit of detection, to validate the manufacturers
published procedures, and to determine if there were matrix effects from
LP.

A major challenge in this research project was to develop confirmation
and quantitation methods with the sensitivity and specificity to test
sweat patch extracts and LP. The LP analyses were especially challenging
because the volume of LP collected was typically in μLs and the expected
drug concentration were similar to blood-drug concentrations (ng/mL).
The specimen volume and drug concentrations are in contrast to urine
collections that are typically in excess of 100 mL and urine-drug
concentrations may be 10 or more times those of blood-drug
concentrations. Standard electron ionization MS methods do not have the
sensitivity to confirm drugs of abuse and their metabolites in LP or in
sweat patch extracts. Therefore, we focused on developing chemical
ionization GC/MS, liquid chromatography/mass spectrometry (LC/MS), and
liquid chromato-graphy tandem mass spectrometry (LC/MS/MS) methods. As
described, known drug-free LP was collected from laboratory volunteers.
These samples were pooled and fortified with drugs of abuse to evaluate
potential MS methods. Calibration curves were prepared by fortifying the
appropriate drug concentrations into the drug-free LP. These data were
used to assess assay linearity and sensitivity.

**3. RESULTS**

**3.1 Collection of Liquid Perspiration: Volumes and Rates**

An important goal of the pilot study was to determine how well the
standard LP collector, which had previously been used with children,
would function when used with adults. The volume of LP collected during
each collection session is presented in figure 1. That figure presents
the following data: the volume of LP collected by the standard collector
in one session (observations 1 -- 45), the volumes of LP collected by
the modified collector in one session (observations

46 -- 76), and the total volume of LP collected in sessions where both
devices were used (observations 77 -- 98).

The volumes collected with the standard collector ranged from 0 μL to 85
μL (the maximum capacity) with a mean of 36.4 μL and a median of 33.5
μL. With the modified collector, specimen volumes ranged from 0 μL to
199 μL with an average of 79.3 μL and a median volume of 71.0 μL.
Collection sessions in which both devices were used yielded total
volumes of LP ranging from 4 μL to 216 μL with a mean of 105.1 μL. It is
important to reiterate the time constraints placed on modified LP
collection: collection was terminated as soon as the standard collector
(administered first) was ready to be removed. Rarely did modified
collection proceed for a full 30 min.

The average duration of the LP collection sessions was 29.5 min (*SD* =
4.4 min) with the standard collector and 26.5 min (*SD* = 3.1 min) with
the modified collector. The average collection rates, measured in
μL/min, are presented with 95 % confidence intervals in figure 2. The
mean collection rate was 1.2 μL/min at session 1 and 1.4 μL/min at
session 2. As hypothesized, the larger modified collector collected
perspiration at a faster rate. For session 1, the average modified
collection rate was 2.7 μL/min and the session 2 mean was 3.3 μL/min.

![](media/image4.wmf)

***Figure 1. Liquid perspiration volumes collected***

Means and 95 % Confidence Interval

![](media/image5.wmf)

# Figure 2. Liquid perspiration collection rates

# 3.2 Participant Perceptions of Collection Methods

Participants rated the specimen collection methods on four
dimensions: 1) discomfort, 2) lengthiness of collection, 3) unpleasant
sensations, and 4) embarrassment. It was hypothesized that the modified
and standard LP collection methods would be perceived as 1) no more
uncomfortable than sweat patch or urine collection, 2) no more demanding
in time required for administration than sweat patch or urine
collection, 3) no more unpleasant sensations than sweat patch or urine
collection, and 4) less embarrassing than urine collection.

At session 1, subject perception data were gathered for all methods
except the sweat patch. Participant mean ratings are presented in figure
3. Each hypothesis was tested using repeated measures analysis of
variance (ANOVA), adjusting the degrees of freedom using Huynh-Feldts\'
Epsilon in cases where Mauchly\'s Test of Sphericity (SPSS, 1999)
revealed the sphericity assumption was not tenable. Consistent with the
first hypothesis, repeated measures ANOVA revealed that the discomfort
ratings for the LP collectors and urine did not statistically differ
(*F*\[1.536, 23.041\] = 0.06, *ns*). Likewise, differences in ratings of
"lengthiness" were not significant (*F*\[2, 26\] = 1.13, *ns*). The
third hypothesis was supported by an ANOVA in which ratings of
"unpleasant sensations" experienced during collection modalities did not
demonstrably differ (*F*\[1.397, 20.961\] = 0.42, *ns*). The ANOVA for
"embarrassment" ratings, however, displayed a trend toward significance
(*F*\[1.00, 14.00\] = 4.38, *p* \< 0.10). This trend offered limited
support for the fourth hypothesis; with pairwise comparisons showing
that participants rated urine collection as more embarrassing than
either of the LP collections.

![](media/image6.wmf)

Grey = Liquid perspiration Dark Grey = Urine White = Sweat patch

***Figure 3. Session perceptions***

Due to the limited sample size that was used at the modified collection
at session 1 (n = 18), we averaged the perception ratings for modified
and standard collections to create composite LP collector ratings.
Within-subject t-tests were conducted to ensure that the LP collector
ratings did not demonstrably differ. T-tests suggested that the two
devices\' ratings were not significantly different on any of the four
dimensions (all *t*\'s \< 1.75, *ns*). In addition, the procedures for
administering the modified and standard were very similar, and the
correlations between participants ratings of each were .44 and above.
Thus, we combined the two sweat collector ratings into a composite. This
allowed us to compare perceptions of urine collection to those of LP
collection with samples of at least 30 participants for each dimension.
T-tests conducted with these data produced results consistent with those
discussed above: Urine and LP collection did not differ on "discomfort"
or "unpleasant sensations," LP collection was perceived

as a significantly lengthier process, and urine collection was rated as
significantly more embarrassing.

At session 2, participant perceptions were assessed for all four types
of specimen collection. The modified and standard LP collection ratings
were again combined to maximize sample size, and analysis of variance
was used to compare perceptions of collection methods on each of the
four dimensions. Consistent with our hypotheses and session 1 findings,
no differences in the LP collection, urine collection, and sweat patch
collection ratings were found for discomfort or unpleasant sensations.
Unlike session 1, at session 2 lengthiness ratings were consistent with
our hypothesis, and the analysis did not show any difference in
participants\' perceptions of how long each method took. On the other
hand, the session 1 finding that urine collection was perceived as the
most embarrassing modality was replicated: the session 2 embarrassment
ANOVA was significant (*F* = 5.01, *p* \< 0.01) and a post-hoc Duncan
test showed urine collection to be more embarrassing than the LP
collectors or the sweat patch.

At each session, participants were asked which collection method they
would most like to use again and which method they would least like to
use again. Unfortunately, responses to the questions were often invalid
(selecting collection methods the respondent had not been administered
and selection of multiple responses) or provided contradictory
information (one respondent selecting the same collection method as both
most and least preferred). Thus no conclusive results were obtained for
this portion of the pilot study. Based on the response styles of the
pilot test participants, these preferences will be reassessed for valid
data collection in the main field test.

###### 3.3 Methods Development: Drug Screening {#methods-development-drug-screening .unnumbered}

LP was collected from approximately 20 "drug free" subjects and was used
as a negative control and to fortify with drugs and drug metabolites. No
immunoassay (IA) interferences were observed using the EIA or RIA
products when testing LP from these collections. Calibration curves were
prepared for the drugs and metabolites in actual LP. The following EIA
and RIA test kits were evaluated: THC, cocaine, opiates, PCP,
amphetamine, and methamphetamine.

The established immunoassay cutoff concentrations are shown in table 2.
The IA was used for screen testing (or drug detection) only and **not**
for quantitative purposes. Therefore, we were most interested in the
qualitative cutoff concentration. The EIA test kits showed more promise
for drug detection in LP than RIA; specifically, in the detection of
THC, THC-COOH, codeine, and morphine. The data were very encouraging
since the sensitivities obtained were consistent with those needed to
screen for drugs of abuse in LP. The EIA screening cutoff concentrations
are shown below.

***Table 2. Screening cutoff concentrations***

  ----------------- --------------- --------------- -------------------- ----------------- -----------
  ***Drug class***  ***Cocaine***   ***Opiates***   ***Amphetamines***   ***Marijuana***   ***PCP***

  *Cutoff           *5 ng/mL*       *\<5 ng/mL*     *5 ng/mL*            *5 ng/mL*         *\<5 ng/mL*
  concentration*                                                                           
  ----------------- --------------- --------------- -------------------- ----------------- -----------

**3.4 Methods Development: MS Confirmations**

In addition to selecting a suitable screening technique for testing the
LP and sweat patch extracts, we explored options for drug/metabolite
confirmations. The most promising technologies were GC/MS, LC/MS, and
LC/MS/MS. Summaries of the methods developed for LP confirmation

testing are shown in table 3. Shown in the table are a summary of the
drugs tested, extraction methods, the calibration curve concentrations,
and the internal standards.

It was our intention to develop a single LC/MS/MS procedure capable of
detecting all the target drugs of abuse and their metabolites in LP.
However, this proved more difficult than anticipated. The limitation was
in our ability to efficiently ionize THC and THC-COOH by electrospray
ionization LC/MS/MS. Presumably, the lack of a functional group that is
readily ionized made electrospray ionization inefficient for cannabinoid
analysis. Therefore, we developed an alternative method using
atmospheric chemical ionization to ionize THC and THC-COOH. However,
experiments to date have shown that atmospheric chemical ionization is
also far less effective for the ionization of THC and THC-COOH than of
the other target drugs and metabolites. We will continue to explore
options to combine the analyses into a single MS/MS analysis. The method
used to test the samples reported here was negative-ion chemical
ionization GC/MS.

To test the hypothesis that the modified device collected LP faster than
the original collector, two t-tests were performed. A within-subjects
analysis, using observations taken from participants who received both
devices at least once, showed that there was a difference between the
collection rates of the two devices (*t*\[26\] = 5.90, *p* \< .001). A
between-subjects analysis, using all of the collection rate data
regardless of whether or not a participant provided both modified and
standard data, also showed that the modified collected LP at a faster
rate than the standard (*t*\[75\] = 4.93, *p* \< .001).

The issue of whether gender, or recent drug use, affected LP collection
rates was addressed with standard collection rate data from session 1.
Although the sample included only three females, LP collection rates did
not appear to differ between males and females. Collection rates for
participants who reported using illicit substances in the past 30 days
(n = 10) did not differ from participants reporting no use (n = 18).
Neither replications of these analyses with session 2 data, nor
finer-grained analyses, for differences between rates of those who
reported using different drugs revealed differences in collection rates.

####### Table 3. Confirmation methods

  ----------------- ----------------- ----------- -------------- ------------------ ------------------
                                                                                    

                    **Cocaine**       **PCP**     **THC/COOH**   **Amphetamines**   **Opiates**

  **Drugs**         Cocaine           PCP         THC            Amphetamine        Morphine

                    Benzoylecgonine               THC-COOH       Methamphetamine    Codeine

                    Ecgonine                                     Phentermine        6-acetylmorphine
                    methylester                                                     

                    Cocaethylene                                 OTC                Heroin
                                                                 sympathomimetic    
                                                                 amines             

  **Method**        LC/MS/MS          LC/MS/MS    GC/MS          LC/MS/MS           LC/MS/MS

  **Extraction**    Solid Phase       Solid Phase Solid Phase    Liquid/Liquid      Solid Phase

  **Calibrators**   0, .5, 1, 5, 10,  0, .25, .5, 0, 1, 2, 4,    0, 20, 50, 100,    0, 1, 5, 10, 25,
                    25, 50, 100, 125  1, 5, 10,   10, 25, 100,   250, 500 and 1000  50, 200, 250 and
                    and 150 ng/mL     25, 50, and 150, 200 and   ng/mL              5100 ng/mL
                                      100 ng/mL   250 ng/mL                         

  **Internal        D3                D5          D3             D5/D8              D5
  Standard**                                                                        

  **Amount**        50 ng             5 ng        10 ng          100 ng             50 ng
  ----------------- ----------------- ----------- -------------- ------------------ ------------------

**3.5 Results: Biological Specimens**

3.5.1 Specimen Summary

Table 4 (Specimen summary) shows the specimens that were collected from
32 subjects during the pilot study.

**3.5.2 Urine Results**

Results from the urine drug screens and confirmation tests are shown in
table 5. The session 1,

urine 1 (U1), and session 2, urine 2 (U2) samples were screened for the
presence of drugs of abuse using a commercial urinalysis immunoassay. In
addition to the tests listed in the proposal, all samples were tested
for both amphetamine and methamphetamine. The table shows that one urine
specimen screened positive for PCP, two for cannabinoids, five for
cocaine, three for opiates, and none for amphetamine or methamphetamine.
Using MS, drugs were confirmed in each urine specimen that screened
positive. In total, nine urine specimens collected from the 32 subjects
tested positive. In subjects 6, 8, 25, and 26, both the U1 and U2 urine
specimens contained drugs.

######## 

**3.5.3 Sweat Patch Results**

######## Results from the sweat patch screen and confirmation testing are shown in table 6. Aliquots of the sweat patch extracts were screened for the presence of drugs of abuse using the validated EIA immunoassay as discussed above. The sweat patch extracts were tested for amphetamine(s), PCP, cannabinoids, cocaine, metabolites, and opiates. The table shows that six extracts screened positive for cocaine and four opiates. None screened positive for amphetamine(s), PCP, or cannabinoids. Using MS, drugs were detected and quantified in each of the sweat patch screened-positive aliquots. 

######## Although the sweat patch for subject 6 did not screen positive for cannabinoids, both urine specimens from this subject were positive for the drug. Therefore, the sweat patch was analyzed by MS and found to contain THC. In total, nine patch aliquots were positive. 

***Table 4. Specimen summary***

  -------- ----------- --------- --------- ------------ ------------ ------------ ------------
  **ID     **Patch**   **Urine   **Urine   **Standard   **Standard   **Modified   **Modified
  \#**                 Pre**     Post**    1**          2**          1**          2**

  **1**    P2          U1        U2        S1           S2                        

  **2**                U1                  S1                        L1           

  **3**                U1                  S1                        L1           

  **4**    P2          U1                  S1                                     

  **5**    P2          U1        U2        S1           S2           L1           

  **6**    P2          U1        U2        S1           S2           L1           

  **7**    P2          U1        U2        S1           S2           L1           

  **8**    P2          U1        U2        S1           S2           L1           

  **9**    P2          U1        U2        S1           S2           L1           

  **10**   P2          U1        U2        S1           S2           L1           L2

  **11**   P2          U1        U2        S1           S2           L1           L2

  **12**               U1        U2        S1                        L1           L2

  **13**   P2          U1        U2        S1           S2           L1           

  **14**   P2          U1        U2        S1                                     L2

  **15**   P2          U1        U2        S1                                     L2

  **16**               U1        U2        S1                                     

  **17**   P2          U1        U2        S1           S2                        L2

  **19**   P2          U1        U2        S1                                     L2

  **20**   P2          U1        U2        S1                                     

  **21**               U1                                                         

  **22**               U1                  S1                                     

  **23**               U1        U2        S1           S2                        L2

  **24**   P2          U1        U2        S1                                     L2

  **25**   P2          U1        U2        S1           S2                        L2

  **26**   P2          U1        U2        S1           S2                        L2

  **27**               U1        U2        S1           S2                        L2

  **28**               U1                                            L1           

  **29**   P2          U1        U2        S1                        L1           L2

  **30**                         U1        S1                        L1           

  **31**               U1        U2                     S2           L1           

  **32**               U1                  S1                        L1           

  **33**   P2          U1        U2        S1           S2           L1           
  -------- ----------- --------- --------- ------------ ------------ ------------ ------------

*Table 5. Urine drug test results*

+----+-------+-----+-------+---------+-----+-----------+------------+
| #  | ##    |     |       |         |     |           | ##         |
| Nu |  Samp |     |       |         |     |           | Confirmati |
| mb | le Sc |     |       |         |     |           | on Results |
| er | reeni |     |       |         |     |           |            |
|    | ng Re |     |       |         |     |           |            |
|    | sults |     |       |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| ## | ## Am | ##  | ## Ca | **BZE   | #   | ########  | **ng/mL**  |
|  I | pheta | PCP | nnabi | (Coc    | # O | # Methamp |            |
| D# | mines |     | noids | aine)** | pia | hetamines |            |
|    |       |     |       |         | tes |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 1  | NEG   | NEG | NEG   | NEG     | NEG | NEG       |            |
| U1 |       |     |       |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 1  | NEG   | NEG | NEG   | NEG     | NEG | NEG       |            |
| U2 |       |     |       |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 2  | NEG   | #   | NEG   | NEG     | NEG | NEG       |            |
| U1 |       | ##  |       |         |     |           |            |
|    |       | NEG |       |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 3  | NEG   | NEG | NEG   | NEG     | NEG | NEG       |            |
| U1 |       |     |       |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 4  | NEG   | NEG | ##    | NEG     | #   | NEG       |            |
| U1 |       |     | # NEG |         | ##  |           |            |
|    |       |     |       |         | NEG |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 5U | NEG   | NEG | NEG   | NEG     | NEG | NEG       |            |
| 1A |       |     |       |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 5U | NEG   | NEG | NEG   | NEG     | NEG | NEG       |            |
| 1B |       |     |       |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 5  | NEG   | NEG | NEG   | NEG     | NEG | NEG       |            |
| U2 |       |     |       |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 6  | NEG   | NEG | POS   | NEG     | NEG | NEG       | THC-COOH   |
| U1 |       |     | ITIVE |         |     |           | 372        |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 6  | NEG   | PO  | POS   | NEG     | NEG | NEG       | PCP 311    |
| U2 |       | SIT | ITIVE |         |     |           | and        |
|    |       | IVE |       |         |     |           | THC-COOH   |
|    |       |     |       |         |     |           | 315        |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 7  | NEG   | NEG | NEG   | NEG     | NEG | NEG       |            |
| U1 |       |     |       |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 7  | NEG   | NEG | ##    | NEG     | NEG | NEG       |            |
| U2 |       |     | # NEG |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 8  | NEG   | NEG | NEG   | P       | NEG | NEG       | Cocaine \< |
| U1 |       |     |       | OSITIVE |     |           | 10 and BZE |
|    |       |     |       |         |     |           | 386        |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 8  | NEG   | NEG | NEG   | P       | NEG | NEG       | Cocaine \> |
| U2 |       |     |       | OSITIVE |     |           | 1000 and   |
|    |       |     |       |         |     |           | BZE \>\>   |
|    |       |     |       |         |     |           | 1000       |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 9  | NEG   | NEG | NEG   | NEG     | NEG | NEG       |            |
| U1 |       |     |       |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 9  | NEG   | NEG | NEG   | NEG     | NEG | NEG       |            |
| U2 |       |     |       |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 10 | NEG   | NEG | NEG   | NEG     | NEG | NEG       |            |
| U1 |       |     |       |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 10 | NEG   | NEG | NEG   | NEG     | NEG | #### NEG  |            |
| U2 |       |     |       |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 11 | NEG   | NEG | NEG   | NEG     | NEG | NEG       |            |
| U1 |       |     |       |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 11 | NEG   | NEG | NEG   | P       | PO  | NEG       | Cocaine \> |
| U2 |       |     |       | OSITIVE | SIT |           | 1000; BZE  |
|    |       |     |       |         | IVE |           | \>\> 1000  |
|    |       |     |       |         |     |           | and        |
|    |       |     |       |         |     |           | morphine   |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 12 | NEG   | NEG | NEG   | P       | PO  | NEG       |            |
| U1 |       |     |       | OSITIVE | SIT |           |            |
|    |       |     |       |         | IVE |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 12 | NEG   | NEG | NEG   | NEG     | NEG | NEG       |            |
| U2 |       |     |       |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 13 | NEG   | NEG | NEG   | NEG     | NEG | NEG       |            |
| U1 |       |     |       |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 13 | NEG   | NEG | NEG   | NEG     | NEG | NEG       |            |
| U2 |       |     |       |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 14 | NEG   | NEG | NEG   | NEG     | NEG | NEG       |            |
| U1 |       |     |       |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 14 | NEG   | NEG | NEG   | NEG     | NEG | NEG       |            |
| U2 |       |     |       |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 15 | NEG   | NEG | NEG   | NEG     | NEG | NEG       |            |
| U1 |       |     |       |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 15 | NEG   | NEG | NEG   | NEG     | NEG | NEG       |            |
| U2 |       |     |       |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 16 | NEG   | NEG | NEG   | NEG     | NEG | NEG       |            |
| U1 |       |     |       |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 17 | NEG   | NEG | NEG   | NEG     | NEG | NEG       |            |
| U1 |       |     |       |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+
| 17 | NEG   | NEG | NEG   | NEG     | NEG | NEG       |            |
| U2 |       |     |       |         |     |           |            |
+----+-------+-----+-------+---------+-----+-----------+------------+

***Table 5. Urine drug test results-Continued***

+----+-------+----+-------+-------+----+---------+-----------------+
| #  | ##    |    |       |       |    |         | ## Confi        |
| Nu |  Samp |    |       |       |    |         | rmation Results |
| mb | le Sc |    |       |       |    |         |                 |
| er | reeni |    |       |       |    |         |                 |
|    | ng Re |    |       |       |    |         |                 |
|    | sults |    |       |       |    |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| ## | ## Am | ## | ## Ca | **BZE | ## | **Meth  | **ng/mL**       |
|  I | pheta |  P | nnabi | (     |  O | ampheta |                 |
| D# | mines | CP | noids | Cocai | pi | mines** |                 |
|    |       |    |       | ne)** | at |         |                 |
|    |       |    |       |       | es |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 19 | NEG   | N  | NEG   | NEG   | N  | NEG     |                 |
| U1 |       | EG |       |       | EG |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 19 | NEG   | N  | NEG   | NEG   | N  | NEG     |                 |
| U2 |       | EG |       |       | EG |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 20 | NEG   | N  | NEG   | NEG   | N  | NEG     |                 |
| U1 |       | EG |       |       | EG |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 20 | NEG   | N  | NEG   | NEG   | N  | NEG     |                 |
| U2 |       | EG |       |       | EG |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 21 | NEG   | N  | NEG   | NEG   | N  | NEG     |                 |
| U1 |       | EG |       |       | EG |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 22 | NEG   | N  | NEG   | NEG   | N  | NEG     |                 |
| U1 |       | EG |       |       | EG |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 23 | NEG   | N  | NEG   | NEG   | N  | NEG     |                 |
| U1 |       | EG |       |       | EG |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 23 | NEG   | N  | NEG   | NEG   | N  | NEG     |                 |
| U2 |       | EG |       |       | EG |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 24 | NEG   | N  | NEG   | NEG   | N  | NEG     |                 |
| U1 |       | EG |       |       | EG |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 24 | NEG   | N  | NEG   | NEG   | N  | NEG     |                 |
| U2 |       | EG |       |       | EG |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 25 | NEG   | N  | NEG   | POS   | N  | NEG     | #### BZE 218    |
| U1 |       | EG |       | ITIVE | EG |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 25 | NEG   | N  | NEG   | POS   | N  | NEG     | BZE 466         |
| U2 |       | EG |       | ITIVE | EG |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 26 | NEG   | N  | NEG   | NEG   | PO | NEG     | Morphine \>\>   |
| U1 |       | EG |       |       | SI |         | 1000 and        |
|    |       |    |       |       | TI |         | codeine 33      |
|    |       |    |       |       | VE |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 26 | NEG   | N  | NEG   | NEG   | PO | NEG     | Morphine \>\>   |
| U2 |       | EG |       |       | SI |         | 1000; codeine   |
|    |       |    |       |       | TI |         | 51 and \^-AM    |
|    |       |    |       |       | VE |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 27 | NEG   | N  | NEG   | NEG   | N  | NEG     |                 |
| U1 |       | EG |       |       | EG |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 27 | NEG   | N  | NEG   | NEG   | N  | NEG     |                 |
| U2 |       | EG |       |       | EG |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 28 | NEG   | N  | NEG   | NEG   | N  | NEG     |                 |
| U1 |       | EG |       |       | EG |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 29 | NEG   | N  | NEG   | NEG   | N  | NEG     |                 |
| U1 |       | EG |       |       | EG |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 29 | NEG   | N  | NEG   | NEG   | N  | NEG     |                 |
| U2 |       | EG |       |       | EG |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 30 | NEG   | N  | NEG   | NEG   | N  | NEG     |                 |
| U1 |       | EG |       |       | EG |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 31 | NEG   | N  | NEG   | NEG   | N  | NEG     |                 |
| U1 |       | EG |       |       | EG |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 31 | NEG   | N  | NEG   | NEG   | N  | NEG     |                 |
| U2 |       | EG |       |       | EG |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 32 | NEG   | N  | NEG   | NEG   | N  | NEG     |                 |
| U1 |       | EG |       |       | EG |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 33 | NEG   | N  | NEG   | NEG   | N  | NEG     |                 |
| U1 |       | EG |       |       | EG |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+
| 33 | NEG   | N  | NEG   | NEG   | N  | NEG     |                 |
| U2 |       | EG |       |       | EG |         |                 |
+----+-------+----+-------+-------+----+---------+-----------------+

***Table 6. Sweat patch drug test results***

  --------------- ---------------------- ----------- ------------------ ------------- ------------- --------------------
  **ID#/Patch**                          **Screen                                                   **Confirmation
                                         Results**                                                  Results**

                  **Methamphetamines**   **PCP**     **Cannabinoids**   **BZE         **Opiates**   **ng/patch**
                                                                        (Cocaine)**                 

  1 P2            NEG                    NEG         NEG                POSITIVE      POSITIVE      Morphine 6; 6-AM 26

                                                                                                    Cocaine 86 and BZE 6

  4 P2            NEG                    NEG         NEG                NEG           NEG           

  5 P2            NEG                    NEG         NEG                NEG           POSITIVE      Codeine 2; morphine
                                                                                                    20; 6-AM 66

  6 P2            NEG                    NEG         NEG                NEG           NEG           THC 2.7, THC-COOH
                                                                                                    negative

  7 P2            NEG                    NEG         NEG                NEG           NEG           

  8 P2            NEG                    NEG         NEG                POSITIVE      NEG           Cocaine \>\> 1000
                                                                                                    and BZE \>1000

  9 P2            NEG                    NEG         NEG                POSITIVE      NEG           Cocaine 67

  10 P2           NEG                    NEG         NEG                POSITIVE      NEG           Cocaine \> 1000 and
                                                                                                    BZE 190

  11 P2           NEG                    NEG         NEG                POSITIVE      POSITIVE      Codeine 3; morphine
                                                                                                    4; 6-AM 26

                                                                                                    Cocaine \> 1000 and
                                                                                                    BE 131

  13 P2           NEG                    NEG         NEG                NEG           NEG           

  14 P2           NEG                    NEG         NEG                NEG           NEG           

  15 P2           NEG                    NEG         NEG                NEG           NEG           

  17 P2           NEG                    NEG         NEG                NEG           NEG           

  19 P2           NEG                    NEG         NEG                NEG           NEG           

  20 P2           NEG                    NEG         NEG                NEG           NEG           

  24 P2           NEG                    NEG         NEG                NEG           NEG           

  25 P2           NEG                    NEG         NEG                POSITIVE      NEG           Cocaine 671 and BZE
                                                                                                    60

  26 P2           NEG                    NEG         NEG                NEG           POSITIVE      Codeine 1.4;
                                                                                                    morphine 2.6; and
                                                                                                    6-AM 5

  29 P2           NEG                    NEG         NEG                NEG           NEG           

  33 P2           NEG                    NEG         NEG                NEG           NEG           
  --------------- ---------------------- ----------- ------------------ ------------- ------------- --------------------

**3.5.4 Liquid Perspiration MS Results**

Results from the LP confirmation testing are shown in table 7. LP
samples were selected for MS confirmation testing if U1, U2, or the
sweat patch tested positive.

Subject 1 tested negative for opiates and cocaine in the urine, positive
for both drug classes in the patch, and positive for opiates and cocaine
in both LP specimens.

Subject 5 tested negative for opiates in the urine samples, positive in
the patch, and positive in both LP specimens.

Subject 6 tested positive for marijuana in both urine samples, positive
by MS in the patch, and negative in both LP specimens. Urine 2 was
positive for PCP, the patch was negative, and both LP samples wee
positive for this drug.

Subject 8 tested positive for cocaine in both urine samples, the patch,
and in both LP specimens.

Subjects 9 and 10 tested negative for cocaine in both urine samples but
positive in the patch and in both LP specimens.

Subject 11 tested positive for cocaine and opiates in only one of two
urine samples and positive for both drugs in the patch. LP 1 contained
only opiates, but LP 2 contained cocaine and opiates.

Subject 25 tested positive for cocaine in both urine samples, the patch,
and both LP samples.

Subject 26 tested positive for opiates in both urine samples, the patch,
and both LP samples.

***Table 7. Liquid perspiration results -- MS***

+--------------------------------+-------------------------------------+
| **Subject#/Session 1 and       | **Confirmation Results - ng/mL**    |
| Session 2**                    |                                     |
+--------------------------------+-------------------------------------+
|                                |                                     |
+--------------------------------+-------------------------------------+
| ## 1 S1                        | Morphine 42; codeine 92             |
|                                |                                     |
|                                | 6-AM 90 and heroin 232              |
|                                |                                     |
|                                | Cocaine and metabolites = negative  |
+--------------------------------+-------------------------------------+
| 1 S2                           | Morphine 15; codeine 22             |
|                                |                                     |
|                                | 6-AM 1 and heroin 8                 |
|                                |                                     |
|                                | Cocaine and metabolites = negative  |
+--------------------------------+-------------------------------------+
| 5 S1                           | Morphine 106; codeine 255           |
|                                |                                     |
|                                | 6-AM 158 and heroin 2               |
+--------------------------------+-------------------------------------+
| 5 S2                           | Morphine 85; codeine 38             |
|                                |                                     |
|                                | 6-AM 287 and heroin 4               |
+--------------------------------+-------------------------------------+
| 6 S1                           | PCP 5                               |
+--------------------------------+-------------------------------------+
| 6 S2                           | PCP 8                               |
+--------------------------------+-------------------------------------+
| 8 S1                           | Cocaine 19; BZE 5                   |
+--------------------------------+-------------------------------------+
| 8 S2                           | Cocaine 132; BZE 19                 |
+--------------------------------+-------------------------------------+
| 9 S1                           | BZE 4                               |
+--------------------------------+-------------------------------------+
| 9 S2                           | BZE 1                               |
+--------------------------------+-------------------------------------+
| 10 S1                          | BZE 3                               |
+--------------------------------+-------------------------------------+
| 10 S2                          | BZE 3                               |
+--------------------------------+-------------------------------------+
| 11 S1                          | Morphine 9; codeine 16              |
|                                |                                     |
|                                | 6-AM 3                              |
|                                |                                     |
|                                | Cocaine and metabolites = negative  |
+--------------------------------+-------------------------------------+
| 11 S2                          | Morphine 11; codeine 11             |
|                                |                                     |
|                                | 6-AM 2                              |
|                                |                                     |
|                                | BZE 14                              |
+--------------------------------+-------------------------------------+
| 25 S1                          | Cocaine 16; BZE 62                  |
+--------------------------------+-------------------------------------+
| 25 S2                          | Cocaine 16; BZE 12                  |
+--------------------------------+-------------------------------------+
| 26 S1                          | Morphine 20; codeine 9              |
+--------------------------------+-------------------------------------+
| 26 S2                          | Morphine 13; codeine 5              |
+--------------------------------+-------------------------------------+

**3.5.5 Liquid Perspiration Screening Results**

Results from the LP screen only testing are shown in table 8. LP samples
were selected for screening only if the urine specimens and the sweat
patch tested negative and the LP volume precluded a full screen and MS
confirmation.

No samples screened positive for marijuana (THC/THCA), PCP or
amphetamine.

Twenty-three LP specimens screened positive or border-line positive
(POSITIVE?) for cocaine and metabolites. Twenty-three positive samples
is a 70 % positive rate. This rate is feasible given the population that
was tested. However, results were not confirmed because the LP volume
precluded MS confirmation.

***Table 8. Liquid perspiration screen only drug test results***

+-----------+--------+-------+-------+----------+--------+----------+
| ### S     | **THC/ | #     | ##    | ###      | ### M  | ### Amp  |
| ample ID# | THCA** | ## Co | # PCP | Morphine | ethamp | hetamine |
|           |        | caine |       |          |        |          |
+-----------+--------+-------+-------+----------+--------+----------+
| 2 L1      | NEG    | POSI  | NEG   | NEG      | NEG    | NEG      |
|           |        | TIVE? |       |          |        |          |
+-----------+--------+-------+-------+----------+--------+----------+
| 3 S1      | NEG    | POS   | NEG   | POSITIVE | NEG    | NEG      |
|           |        | ITIVE |       |          |        |          |
+-----------+--------+-------+-------+----------+--------+----------+
| 4 S1      | NEG    | POS   | NEG   | NEG      | NEG    | NEG\*    |
|           |        | ITIVE |       |          |        |          |
+-----------+--------+-------+-------+----------+--------+----------+
| 12 L1     | NEG    | POS   | NEG   | POSITIVE | NEG    | NEG\*    |
|           |        | ITIVE |       |          |        |          |
+-----------+--------+-------+-------+----------+--------+----------+
| 12 L2\*   | NEG    | POS   | NEG   | POSITIVE | NEG    | NEG      |
|           |        | ITIVE |       |          |        |          |
+-----------+--------+-------+-------+----------+--------+----------+
| 13 L1     | NEG    | POS   | NEG   | NEG      | NEG    | NEG      |
|           |        | ITIVE |       |          |        |          |
+-----------+--------+-------+-------+----------+--------+----------+
| 13 S2\*   | NEG    | NEG   | NEG   | NEG      | NEG    | NEG      |
+-----------+--------+-------+-------+----------+--------+----------+
| 14 S1\*   | NEG    | NEG   | NEG   | NEG      | NEG    | NEG      |
+-----------+--------+-------+-------+----------+--------+----------+
| 14 L2     | NEG    | POS   | NEG   | NEG      | NEG    | NEG      |
|           |        | ITIVE |       |          |        |          |
+-----------+--------+-------+-------+----------+--------+----------+
| 15 S1\*   | NEG    | NEG   | NEG   | NEG      | NEG    | NEG      |
+-----------+--------+-------+-------+----------+--------+----------+
| 15 L2\*   | NEG    | POSI  | NEG   | NEG      | NEG    | NEG      |
|           |        | TIVE? |       |          |        |          |
+-----------+--------+-------+-------+----------+--------+----------+
| 16 S1     | NEG    | POS   | NEG   | POSITIVE | NEG    | NEG\*    |
|           |        | ITIVE |       |          |        |          |
+-----------+--------+-------+-------+----------+--------+----------+
| 17 S1     | NEG    | NEG   | NEG   | NEG      | NEG    | NEG\*    |
+-----------+--------+-------+-------+----------+--------+----------+
| 17 L2     | NEG    | POSI  | NEG   | NEG      | NEG    | NEG      |
|           |        | TIVE? |       |          |        |          |
+-----------+--------+-------+-------+----------+--------+----------+
| 19 S1\*   | NEG    | NEG   | NEG   | NEG      | NEG    | NEG      |
+-----------+--------+-------+-------+----------+--------+----------+
| 19 L2     | NEG    | POS   | NEG   | NEG      | NEG    | NEG\*    |
|           |        | ITIVE |       |          |        |          |
+-----------+--------+-------+-------+----------+--------+----------+
| 20 S1\*   | NEG    | NEG   | NEG   | NEG      | NEG    | NEG      |
+-----------+--------+-------+-------+----------+--------+----------+
| 22 S1     | NEG    | POS   | NEG   | NEG      | NEG    | NEG      |
|           |        | ITIVE |       |          |        |          |
+-----------+--------+-------+-------+----------+--------+----------+
| 23 S1\*   | NEG    | POS   | NEG   | POSITIVE | NEG    | NEG      |
|           |        | ITIVE |       |          |        |          |
+-----------+--------+-------+-------+----------+--------+----------+
| 23 L2     | NEG    | POS   | NEG   | POSITIVE | NEG    | NEG      |
|           |        | ITIVE |       |          |        |          |
+-----------+--------+-------+-------+----------+--------+----------+
| 24 S1\*   | NEG    | POS   | NEG   | POSITIVE | NEG    | NEG      |
|           |        | ITIVE |       |          |        |          |
+-----------+--------+-------+-------+----------+--------+----------+
| 24 L2     | NEG    | POS   | NEG   | POSITIVE | NEG    | NEG      |
|           |        | ITIVE |       |          |        |          |
+-----------+--------+-------+-------+----------+--------+----------+
| 27 S1     | NEG    | POS   | NEG   | NEG      | NEG    | NEG\*    |
|           |        | ITIVE |       |          |        |          |
+-----------+--------+-------+-------+----------+--------+----------+
| 27 S2\*   | NEG    | POS   | NEG   | NEG      | NEG    | NEG      |
|           |        | ITIVE |       |          |        |          |
+-----------+--------+-------+-------+----------+--------+----------+
| 28 L1     | NEG    | POS   | NEG   | NEG      | NEG    | NEG\*    |
|           |        | ITIVE |       |          |        |          |
+-----------+--------+-------+-------+----------+--------+----------+
| 29 L1\*   | NEG    | POS   | NEG   | POSITIVE | NEG    | NEG      |
|           |        | ITIVE |       |          |        |          |
+-----------+--------+-------+-------+----------+--------+----------+
| 29 L2\*   | NEG    | NEG   | NEG   | NEG      | NEG    | NEG      |
+-----------+--------+-------+-------+----------+--------+----------+
| 30 L1     | NEG    | POS   | NEG   | POSITIVE | NEG    | NEG      |
|           |        | ITIVE |       |          |        |          |
+-----------+--------+-------+-------+----------+--------+----------+
| 31 L1\*   | NEG    | NEG   | NEG   | NEG      | NEG    | NEG      |
+-----------+--------+-------+-------+----------+--------+----------+
| 31 S2\*   | NEG    | NEG   | NEG   | NEG      | NEG    | NEG      |
+-----------+--------+-------+-------+----------+--------+----------+
| 32 S1     | NEG    | POS   | NEG   | NEG      | NEG    | NEG      |
|           |        | ITIVE |       |          |        |          |
+-----------+--------+-------+-------+----------+--------+----------+
| 33 S1     | NEG    | POS   | NEG   | NEG      | POS    | NEG      |
|           |        | ITIVE |       |          | ITIVE? |          |
+-----------+--------+-------+-------+----------+--------+----------+
| 33 S2\*   | NEG    | NEG   | NEG   | NEG      | NEG    | NEG      |
+-----------+--------+-------+-------+----------+--------+----------+
| \*Limited |        |       |       |          |        |          |
| sample    |        |       |       |          |        |          |
| volume    |        |       |       |          |        |          |
|           |        |       |       |          |        |          |
| POSITIVE? |        |       |       |          |        |          |
| =         |        |       |       |          |        |          |
| Bo        |        |       |       |          |        |          |
| rder-line |        |       |       |          |        |          |
| positive  |        |       |       |          |        |          |
|           |        |       |       |          |        |          |
| S1 or S2  |        |       |       |          |        |          |
| =         |        |       |       |          |        |          |
| Standard  |        |       |       |          |        |          |
| collector |        |       |       |          |        |          |
|           |        |       |       |          |        |          |
| L1 or L2  |        |       |       |          |        |          |
| =         |        |       |       |          |        |          |
| Modified  |        |       |       |          |        |          |
| collector |        |       |       |          |        |          |
+-----------+--------+-------+-------+----------+--------+----------+

Ten LP specimens screened positive or border-line positive for opiates.
Both LP specimens from 12, 23, and 24 tested positive. Even though these
results were not confirmed by MS, they are very suggestive of opiate use
by these subjects. Subjects 12 and 23 did not provide a sweat patch;
however, both urine specimens were negative for opiates. The test
results for subject 24 showed that the sweat patch and both urine
specimens were negative for opiates.

A single LP specimen screened border-line positive for methamphetamine.

**3.5.6 A Comparison of MS Confirmed Urine, Sweat Patch, and LP
Results**

Table 9 shows that 11 urine specimens tested negative when drugs were
detected in either the sweat patch or the LP specimens. One sweat patch
sample tested negative (subject 6) when the urine or LP specimens tested
positive. Three LP specimens tested negative when the sweat patch or
urine samples were drug positive. LP appears to be a good to excellent
sample for the detection of opiates and cocaine, and it was consistent
with urine and out performed the sweat patch for the detection of PCP.
However, it was outperformed by the urine and the sweat patch for the
detection of cannabinoids. No amphetamine(s) were detected in any of the
samples.

***Table 9. Summary of positive test results***

+-----------+-----------+-----------+-----------+-----------+-----------+
| **ID#**   |           |           | *         |           |           |
|           |           |           | *Positive |           |           |
|           |           |           | Test      |           |           |
|           |           |           | Results** |           |           |
+-----------+-----------+-----------+-----------+-----------+-----------+
|           | **Amps**  | **PCP**   | **        | **BE      | **        |
|           |           |           | Cannabs** | (C        | Opiates** |
|           |           |           |           | ocaine)** |           |
+-----------+-----------+-----------+-----------+-----------+-----------+
| 1U1       |           |           |           | NEG       | NEG       |
|           |           |           |           |           |           |
| 1U2       |           |           |           | NEG       | NEG       |
|           |           |           |           |           |           |
| Patch     |           |           |           | POSITIVE  | POSITIVE  |
|           |           |           |           |           |           |
| LP1       |           |           |           | POSITIVE  | POSITIVE  |
|           |           |           |           |           |           |
| LP2       |           |           |           | POSITIVE  | POSITIVE  |
+-----------+-----------+-----------+-----------+-----------+-----------+
| 5U1A      |           |           |           |           | NEG       |
|           |           |           |           |           |           |
| 5U1B      |           |           |           |           | NEG       |
|           |           |           |           |           |           |
| 5U2       |           |           |           |           | NEG       |
|           |           |           |           |           |           |
| Patch     |           |           |           |           | POSITIVE  |
|           |           |           |           |           |           |
| LP1       |           |           |           |           | POSITIVE  |
|           |           |           |           |           |           |
| LP2       |           |           |           |           | POSITIVE  |
+-----------+-----------+-----------+-----------+-----------+-----------+
| 6U1       |           | NEG       | POSITIVE  |           |           |
|           |           |           |           |           |           |
| 6U2       |           | POSITIVE  | POSITIVE  |           |           |
|           |           |           |           |           |           |
| Patch     |           | NEG       | POSITIVE  |           |           |
|           |           |           |           |           |           |
| LP1       |           | POSITIVE  | NEG       |           |           |
|           |           |           |           |           |           |
| LP2       |           | POSITIVE  | NEG       |           |           |
+-----------+-----------+-----------+-----------+-----------+-----------+
| 8U1       |           |           |           | POSITIVE  |           |
|           |           |           |           |           |           |
| 8U2       |           |           |           | POSITIVE  |           |
|           |           |           |           |           |           |
| Patch     |           |           |           | POSITIVE  |           |
|           |           |           |           |           |           |
| LP1       |           |           |           | POSITIVE  |           |
|           |           |           |           |           |           |
| LP2       |           |           |           | POSITIVE  |           |
+-----------+-----------+-----------+-----------+-----------+-----------+
| 9U1       |           |           |           | NEG       |           |
|           |           |           |           |           |           |
| 9U2       |           |           |           | NEG       |           |
|           |           |           |           |           |           |
| Patch     |           |           |           | POSITIVE  |           |
|           |           |           |           |           |           |
| LP1       |           |           |           | POSITIVE  |           |
|           |           |           |           |           |           |
| LP2       |           |           |           | POSITIVE  |           |
+-----------+-----------+-----------+-----------+-----------+-----------+
| 10U1      |           |           |           | NEG       |           |
|           |           |           |           |           |           |
| 10U2      |           |           |           | NEG       |           |
|           |           |           |           |           |           |
| Patch     |           |           |           | POSITIVE  |           |
|           |           |           |           |           |           |
| LP1       |           |           |           | POSITIVE  |           |
|           |           |           |           |           |           |
| LP2       |           |           |           | POSITIVE  |           |
+-----------+-----------+-----------+-----------+-----------+-----------+
| 11U1      |           |           |           | NEG       | NEG       |
|           |           |           |           |           |           |
| 11U2      |           |           |           | POSITIVE  | POSITIVE  |
|           |           |           |           |           |           |
| Patch     |           |           |           | POSITIVE  | POSITIVE  |
|           |           |           |           |           |           |
| LP1       |           |           |           | NEG       | POSITIVE  |
|           |           |           |           |           |           |
| LP2       |           |           |           | POSITIVE  | POSITIVE  |
+-----------+-----------+-----------+-----------+-----------+-----------+
| 25U1      |           |           |           | POSITIVE  |           |
|           |           |           |           |           |           |
| 25U2      |           |           |           | POSITIVE  |           |
|           |           |           |           |           |           |
| Patch     |           |           |           | POSITIVE  |           |
|           |           |           |           |           |           |
| LP1       |           |           |           | POSITIVE  |           |
|           |           |           |           |           |           |
| LP2       |           |           |           | POSITIVE  |           |
+-----------+-----------+-----------+-----------+-----------+-----------+
| 26U1      |           |           |           |           | POSITIVE  |
|           |           |           |           |           |           |
| 26U2      |           |           |           |           | POSITIVE  |
|           |           |           |           |           |           |
| Patch     |           |           |           |           | POSITIVE  |
|           |           |           |           |           |           |
| LP1       |           |           |           |           | POSITIVE  |
|           |           |           |           |           |           |
| LP2       |           |           |           |           | POSITIVE  |
+-----------+-----------+-----------+-----------+-----------+-----------+

**4. DISCUSSION**

The pilot study achieved several important objectives. As a preparation
for the main field study, the pilot study demonstrated that an LP
collection device could be used to harvest LP specimens in a criminal
justice setting, and that drugs of abuse could be detected in LP
specimens using available analytic procedures. The study also identified
challenges, both practical and analytic, to the use of the LP method for
drug testing. The 25 min to 30 min collection time may be inconvenient
in many settings, and the small volume of LP collected poses significant
technical difficulties in the analysis; both issues deserve close
attention as we prepare for the main field study. Because the results
indicated that the larger, specially engineered collector was capable of
collecting larger volumes at a faster rate than the standard collector,
the modified (and similarly modified devices) will be considered for use
in the field test.

The arrestees appeared to have had few (if any) problems with the data
collection procedures. The recruitment of subjects and the collection of
specimens proceeded without any serious impediments. The management and
staff of the pretrial agency were helpful and supportive of the research
project, and most arrestees approached to participate in the research
volunteered to do so. Subjects' ratings of the different collection
procedures indicated that the LP procedures were perceived as no more
discomforting or unpleasant than a urine collection and the sweat patch,
and that the LP procedures were viewed as significantly less
embarrassing than a urine collection.

Substantial strides were made in the development and validation of the
analytic methods for screening and confirmation of drugs in LP
specimens. Preliminary IA experiments showed that the EIA kits were more
promising for drug screening than RIA, particularly for the detection of
amphetamine, methamphetamine, THC, and THC metabolite. An examination of
the MS confirmation procedures (GC/MS, LC/MS, and LC/MS/MS) found that
specific and sensitive methods could be developed for the analysis of
LP. However, inefficiencies in THC and THC-COOH ionization using
LC/MS/MS has led to continued research for an alternative method.
Currently, we are using negative ion chemical ionization GC/MS and
exploring the use of derivatization and then LC/MS/MS analysis.

The LP specimens of nine subjects yielded MS confirmed positives for
drugs. Eight of these subjects tested positive for cocaine/metabolites
and opiates/metabolites (or both); one tested positive for PCP. In only
one subject did the urine tests detected a drug (cannabinoids) that was
not detected in the LP specimens (table 9). In four subjects, LP tests
detected drugs (two opiate and two cocaine positives) that the urine
tests did not detect. However, in all four subjects the sweat patch
specimen tested positive for drugs detected in LP. In addition, the LP
screening tests yielded an astonishing *70 %* positive rate for cocaine
(table 8). Unfortunately, because of the limited volume of the LP
specimens these positive screening results could not be confirmed.
Nonetheless, these findings indicate that not only is LP a promising
matrix for drug testing, but that it may be superior to urine for
detecting cocaine and opiate use. The results suggest that LP may not be
as effective as urine in detecting cannabinoids. However, only one
subject tested positive for cannabinoids. The very low number of
positives found for THC and THC-COOH, as well as for PCP and
amphetamines in the pilot study, precludes drawing any conclusions in
this regard at this time.

5.  **CONCLUSIONS**

Several conclusions were reached from this pilot study as follows:

-   Liquid perspiration can be harvested in criminal justice settings
    using the modified or standard collector. Minimal training was
    required for the project staff to effectively use the collection
    apparatus, and the device was readily accepted by both agency staff
    and arrestees.

-   The modified collector can be used in criminal justice settings to
    collect LP specimens in a noninvasive, totally observed manner, and
    the procedure was well tolerated by the subjects. Subjects found the
    modified collector to be no more unpleasant and significantly less
    embarrassing than a urine collection.

-   Existing, commercially available drug screening methods can be used
    effectively to screen for drugs of abuse in LP specimens. Both EIA
    and RIA showed promise. EIA was selected due to its better
    sensitivity for amphetamines and cannabinoids.

-   MS procedures were developed and validated for confirmation of drugs
    of abuse in LP.

-   Drugs of abuse and their metabolites are excreted in LP. This was
    suggested by the research that has been reported using the sweat
    patch, but had not actually been demonstrated until this pilot study
    was performed.

-   LP may be a preferable specimen to urine for the detection of drug
    use by arrestees in the criminal justice system (tables 8 and 9).
    These tables show that LP was very effective in detecting drug use
    by arrestees. Screening results show that several additional
    subjects were identified as cocaine and opiate positive using LP
    testing. MS results identified six incidences in which the LP was
    drug positive and the corresponding urine specimen tested negative.

-   The volume of LP collected is a limitation. The volume is sufficient
    to screen for the drugs of abuse or to perform a limited screen and
    a confirmation of no more than one or two drugs. The specially
    engineered collector appears to collect larger volumes at a faster
    rate than the standard collector. Modified LP devices need to be
    further explored for use in the field test.

-   Further study of LP is needed to fully understand the advantages and
    limitations of the specimen and the collection technique. For
    example, no pilot-study arrestees tested positive for
    amphetamine(s), only one tested positive for cannabinoids, and one
    for PCP. This is an insufficient number of subjects and test results
    from which to draw significant conclusions. Also, THC and THC-COOH
    were not detected in any LP specimens, while THC-COOH was detected
    in the subject's urine and THC was detected in his sweat patch. LP
    appeared to be a superior specimen to urine for the detection of
    cocaine and opiates, but again a limited number of subjects and
    specimens were tested.

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[^1]: Certain commercial equipment, instruments, or materials are
    identified in this paper to adequately specify the experimental
    procedure. Such identification does not imply recommendation or
    endorsement by the National Institute of Standards and Technology
    (NIST), nor does it imply that the equipment, instruments, or
    materials are necessarily the best available for the purpose.

[^2]: Items in parentheses refer to References in section 6.