Transcript Paul Cary Q & A LADCP 2=06

Advanced Drug Detection
Questions & Answers
By: Paul L. Cary
Toxicology Laboratory
University of Missouri
What is meant by the term
“zero tolerance” drug testing?
Why do drug tests use a cutoff
anyway? Isn’t it possible to
detect drugs down to a level
of zero?
Negative or None Detected Results
indicates that no drugs or breakdown
products (metabolites), tested for, were
detected in the sample tested
 does not mean NO drugs present
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Negative/None Detected Interpretation
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donor is not using a drug that can be detected
by the test OR
donor not using enough drug
donor’s drug use is too infrequent
collection too long after drug use
urine is tampered
test being used not sensitive enough
Negative/None Detected Interpretation
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assess none detected drug testing results
in the context of your client’s overall
program compliance (or noncompliance) and their life’s skills success
(or lack thereof)
Positive Test Result Interpretation
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indicates that drug(s) or breakdown products
(metabolites), tested for, were detected in the
sample tested
drug presence is above the “cutoff” level
greatest confidence achieved with
confirmation
ALWAYS confirm positive results in original
sample
Typical Cutoff Levels
screening & confirmation
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amphetamines *
benzodiazepines
cannabinoids *
cocaine (crack)*
opiates (heroin) *
phencyclidine (P CP) *
alcohol
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1000 ng/mL
300 ng/mL
50 ng/mL
300 ng/mL
300/2000 ng/mL
25 ng/mL
20 mg/dL
SAMHSA (formerly NIDA) drugs
500 ng/mL
variable
15 ng/mL
150 ng/mL
variable
25 ng/mL
10 mg/dL
How should I deal with a
client who claims to have used
or ingested something that
caused a “false” positive?
Drug tests & cross reactivity:
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screening tests can and do react to “non-target”
compounds
 amphetamines
 benzodiazepines
obtain list of interfering compounds from lab or
on-site test vendor
on-site testing devices (“instant” tests) are only
60-70% accurate
confirm positive results
Client Accountability:
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the court should not assume the role of client “excuse
evaluator”
clients need to be held responsible for their own behavior
and maintaining a drug-free physiology
if testing performed appropriately (with confirmation) –
HOW the drug got into their sample is mostly irrelevant
a positive drug test results put the client in violation
as a practical and resource matter – the court cannot
afford to argue over or dispute with every client who has
a positive test result or comes up with a new excuse
I heard that urine drug
concentrations have no
meaning or interpretive value
for assessing client drug use
behavior - is that true ?
Drug Tests are Qualitative
screening/monitoring drug tests are
designed to determine the presence or
absence of drugs - NOT their
concentration
 drug tests are NOT quantitative
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Drug concentrations or levels associated
with urine drug testing are, for the most
part, USELESS !
cocaine metabolite
 opiates
 cannabinoids
 amphetamines
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517 ng/mL
negative
negative
negative
THE ISSUE:
Urine drug concentrations are of little or no
interpretative value. The utilization of urine drug
test levels by drug courts generally produces
interpretations that are inappropriate, factually
unsupportable and without a scientific
foundation. Worst of all for the court system,
these urine drug level interpretations have no
forensic merit.
Scientific Rationale
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Technical Issues
 testing
not linear
 tests measure total drug concentrations
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Physiological
 variability
of urine output
 differential elimination of drug components
The Vicious Cycle
Labs know the
urine levels are
of little or no interpretive value, and
yet are reported
because of customer
demand
Labs are reluctant
to discontinue
practice and risk
revenue loss or customer
dissatisfaction
Courts provided with
a number assume
it has value and
requires interpretation
Courts become
dependent on
urine levels
attempting to
define client drug
use behavior and
justify sanctions &
rewards
“Expected Values:
When the test is used as a qualitative assay,
the amount of drugs and metabolites detected
by the assay in any given specimen cannot be
estimated. The assay results distinguish
between positive and negative specimens only.”
Advantages of Eliminating Drug Levels
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court decisions have a strong scientific basis &
forensically sound
no longer attempt to interpret data that is not
interpretable
greater confidence in decision making process
removes ambiguity associated with manipulating
numbers that few in drug court are trained to do
adds additional fairness/equity in sanctions &
incentives process
NDCI Practitioner Fact Sheet:
http://www.ndci.org/publications/
drugtestingfactsheet.pdf
Does marijuana really stay in
a client’s body for 30 days or
longer after use?
Cannabinoid Detection in Urine
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Conventional wisdom has led to the common
assumption that cannabinoids will remain
detectable in urine for 30 days or longer following
the use of marijuana.
RESULT:
 delay of therapeutic intervention
 hindered timely use of judicial sanctioning
 fostered denial of marijuana usage by clients
Many of the early cannabinoid studies often
cited as proof of 30+ day detection periods
suffered from . . .
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unable to ensure abstinence during the study
detection cutoffs used very low
used testing methods no longer available poor specificity
Cannabinoids - Recent/Relevant Research
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30+ day detection window often exaggerates
duration of detection window
reasonable & pragmatic court guidance
detection time: at 50 ng/mL cutoff
 1 - 3 days for single event/occasional use
 up to 10 days for heavy chronic use
detection time: at 20 ng/mL cutoff
 5-7 days for single event/occasional use
 up to 21 days for heavy chronic use
Recent Cannabinoid Use versus Non-recent
use (double sanction issue):
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How do drug courts discriminate between new
drug exposure and continued elimination from
previous (chronic) use ?
 an issue only in first phase of program
 only drug that poses concern is cannabinoids
 “two negative test” rule – two back-to-back
negative drug tests post clean out
Full Text of:
The Marijuana Detection Window: Determining the Length
of Time Cannabinoids Will Remain Detectable in Urine
following Smoking: A Critical Review of Relevant
Research and Cannabinoid Detection Guidance for Drug
Courts, Drug Court Review (publication of the National
Drug Court Institute, Arlington Virginia Volume V, Issue 1,
Spring 2006, pages 23-58.
What does it mean when a
sample is reported as “dilute” or
as having a “low creatinine” ?
What is creatinine ?
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creatinine is derived from the non-enzymatic dehydration of
creatine in skeletal muscle
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creatinine is produced by the body at a relatively constant
rate throughout the day
creatinine is a compound that is unique to biological
material (i.e. urine, other body fluids)
creatinine can be measured to determine the “strength” or
concentration of a urine sample
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Water contains no drugs!
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easiest, cheapest, simplest
urines with a creatinines of less than 20 mg/dL are
considered “dilute” and rarely reflect an accurate
picture of recent drug use
dilute samples are like water than like urine
all drug court samples should be screened for
creatinine
How are creatinine measurements used ?
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normal human creatinine levels will vary during the day
based upon fluid intake - healthy individuals will rarely
produce urine samples with creatinines of less than 20
mg/dL
incidence of low creatinines in a population undergoing
random drug testing is 3 - 5 times greater than a nondrug tested population
any fluid intake dilutes the concentration of drugs in
urine (along with the creatinine)
Fluid intake & dilute samples:
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rapid intake of 2 quarts of fluid routinely
produces low creatinines & negative urine
drug tests within one hour
rapid intake of 4 quarts of fluid almost
always produces low creatinines and
negative urine drug tests within one hour
limit fluid intake prior to collection
What is the most common
method client’s use to “beat the
drug test” and how can this
cheating be controlled ?
Basics of Specimen Tampering The Three Approaches
 dilution
 adulteration
 substitution
Urine Specimen Dilution:
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most common form of tampering
pre collection dilution (hydration, water
loading, flushing)
post collection dilution
creatinine measurement
dilution detection (specimen validity tests SVT)
Urine Specimen Adulteration
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addition of foreign substances designed to
“mask” drug presence
post-collection tampering
low-tech adulterants that cause “pH shift”
(lime, vinegar, bleach, ammonia, lemon,
drano)
low-tech adulterants that disrupt testing
chemistry (salt, methanol, detergent)
common “high-tech” adulterants
Urinaid, Byrd Laboratories
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gluteraldehyde
sterilization chemical
deactivates most screening tests - producing
false negative results
can be identified by laboratories employing
specimen validity checks
effects can not be reversed
Klear & Whizzies
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potassium nitrite, sodium nitrite
analytical chemistry
compromises the confirmation (GC/MS) of
some drugs, notably carboxy-THC
oxidizes drug and standards
can be identified by laboratories employing
specimen validity checks
effects can be reversed
Urine Luck
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pyridinium chlorochromate/dichromate
oxidizing agent in organic synthesis
compromises the confirmation (GC/MS)
carboxy-THC and opiates
can also effect screening tests
oxidizes drug and standards
can be identified by laboratories employing
specimen validity checks
effects can not be reversed
Urine Specimen Substitution
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replacing donor urine sample with another
drug-free specimen
biological substitution - someone else’s “clean”
urine
non-biological substitution - replacing urine
with urine “look-a-like” sample (diet
Mountain Dew, water with food coloring)
non-biologicals can be detected with creatinine
testing
Controlling Specimen Tampering
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develop challenging collection strategy - ie. make
the testing unannounced and RANDOM!
directly observed collections is the most effective
approach to preventing adulteration and
substitution
inspect sample - train collection staff
keep abreast of tampering techniques
take temperature measurements (90˚ - 100˚ F)
use laboratory employs specimen validity tests & use
with on-site devices
Specimen Validity Tests (SVT)
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creatinine, UUN
specific gravity
pH
nitrites
gluteraldehyde
pyridine
chromium
Request SVT from testing laboratory or use
dip-stick SVT products for on-site testing
The “witnessed” collection (for urine)
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single most important aspect of effective drug
testing program
urine collections not witnessed are of little or
no assessment value
denial component of substance abuse requires
“direct observation” collections of participants
What’s the best specimen for
abused substance testing in a
drug court population where
we are monitoring abstinence?
Drug Testing Specimens
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urine - current specimen of choice
 generally readily available - large quantities
 contains high concentrations of drugs
 good analytical specimen
 provides both recent and past usage
alternative specimens
 breath
 hair
 sweat - patch test
 saliva - oral fluids
 eye scanning devices
Relative
Detection
Times –
by
Specimen
Characteristics of a Good Drug Test:
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scientifically valid
 employs proven methods & techniques
 accepted by the scientific community
therapeutically beneficial
 provides accurate profile of client’s drug use
 provides rapid results for appropriate response
legally defensible
 able to withstand challenge
 established court track record
 scrutinized by legal/judicial review
Your Questions ?
email address:
 [email protected]