Screening and
Assessing Adolescents for Substance Use Disorders
Appendix C -- Drug Identification and Testing in The Juvenile Justice System
This appendix on laboratory testing is an excerpt from Drug Identification and Testing in the Juvenile Justice System, by Ann H.
Crowe, American Probation and Parole Association, and Shay Bilchik, Administrator, Office of Juvenile Justice and Delinquency Prevention. Published by the Office of Justice Programs, U.S.
Department of Justice in May 1998.
The full text is available at http://www.ncjrs.org/ojjdp/drugid/contents.html (this excerpt accessed August 10, 1998).
Drug Recognition Techniques
Drug recognition techniques were developed originally by the Los Angeles Police Department to help law enforcement officers identify drug-impaired motorists in a traffic arrest situation. The Orange County, California, Probation Department later applied and adapted the techniques for use in community corrections settings, using their findings to expand the period for detecting illicit drug use.
Drug recognition techniques are systematic and standardized evaluation techniques for detecting signs and symptoms of substance abuse. All the areas evaluated are observable physical reactions to specific types of drugs.
Three key elements in the process are
- Verifying that the person's physical responses deviate from normal
- Ruling out a cause that is not drug related
- Using diagnostic procedures to determine the category or combination of substances that are likely to cause the impairment
A skilled practitioner can determine, with a high degree of accuracy, whether a youth has used some substances recently. Drug recognition techniques include the identification of the category of chemical substances ingested, although it is not possible to identify specific drugs within a classification. These techniques can determine whether a youth currently is under the influence of substances or has used a particular drug or combination of drugs within 72 hours of ingestion. However, it is not possible to determine the amount of the substance consumed.
Using drug recognition techniques is cost efficient because they often can eliminate the need for costly urinalysis by screening out those youth who do not show symptoms of current or recent substance use. This does not mean these youth have not used illicit drugs; however, if the symptoms are not apparent through drug recognition techniques, it is unlikely there is a sufficient quantity of most drugs, or their metabolites, left in the body for urinalysis to produce a positive test result. (Marijuana and PCP may be exceptions, as low levels sometimes can be detected through urinalysis for as long as 3 to 4 weeks.) Initial training for staff to become proficient in using these techniques can be costly, but once the staff are trained, ongoing expenses are minimal.
Use of drug recognition techniques provides immediate results with which to confront youth. These techniques are minimally intrusive in detecting illicit drug use, compared with the collection of body fluids required for urinalysis. The process is systematic and standardized, reducing the possibility of bias or error by trained staff.
Not all categories of drugs are equally detectable using drug recognition techniques, and the specific drugs ingested cannot be determined. Thus, the techniques used alone may not be conclusive in determining the exact substance used or in detecting the effects of illicit drugs that have minimal influence on the physical responses measured by the techniques.
There are 12 steps in the drug recognition process:
- Drug history
- Breath alcohol test
- Divided-attention psychophysical tests
- Medical questions and initial observations
- Examination for muscle rigidity
- Examination for injection sites
- Examination of vital signs
- Darkroom examination
- Examination of the eyes
- Youth's statements and additional observations by staff
- Opinions of the evaluator
- Toxicological examination
It is imperative that practitioners be well trained in using these techniques and that each step be followed precisely to preserve the credibility and integrity of the drug recognition process.
Chemical Testing
Chemical testing is the most physically intrusive and the most expensive of the three methods of identifying illicit drug use; however, it is also the most accurate. Several scientific methods are available for detecting illicit drug use in individuals, including urinalysis, blood analysis, hair analysis, and saliva tests. However, saliva and breath analysis for alcohol and urinalysis for drugs other than alcohol are the methods currently recommended because they are reliable and relatively inexpensive compared with other methods of chemical testing.
Immunoassay tests generally are used for initial tests, and they are considered reliable for detecting the presence of illicit drugs in a person's system. These tests depend on naturally occurring reactions between antibodies and antigens. A specific antibody can be produced to react with a particular antigen, such as a drug. A "tag" is chemically attached to a sample of the illicit drug to be detected.
Immunoassay procedures vary primarily in the tag used to produce the reaction. The following immunoassay methods of urinalysis have been developed. Often, the type of tag used to produce the chemical reaction is reflected in the name of the test:
- Radioimmunoassay (RIA)
- Latex agglutination immunoassay (LAIA)
- Enzyme immunoassay (EIA)
- Fluorescence polarization immunoassay (FPIA)
- Kinetic interaction of microparticles in solution (KIMS)
- Ascent multi-immunoassay (AMIA)
During an immunoassay process, the reagent (the tagged drug), the urine, and the antibody are combined. The tagged drug and the untagged drug (if present in the urine) compete for binding sites with the antibody. If a sufficient concentration of drug is in the urine, little of the tagged drug can bind with the antibody. The results will indicate the amount of tagged drug that either was or was not bound with the antibody. These results are compared with a sample containing a known amount of a drug to determine whether the urine contained a measurable amount of the substance.
Immunoassay tests provide qualitative results that indicate the presence or absence of a chemical relative to a certain cutoff level. However, except for the RIA method used primarily by the military, which provides quantitative results, they cannot indicate the actual amount of the illicit drug in the system or when it was ingested.
Chromatography methods of urinalysis extract the drug from the urine in a concentrated form. This is then processed by laboratory instruments using heat or liquids, causing the drug metabolites to separate. These methodologies include gas chromatography/ mass spectrometry (GC/MS), gas chromatography (GC), and high-performance liquid chromatography (HPLC). They are the only other procedures providing a quantitative reading of the level of drugs in one's system. GC/MS is considered the "gold standard" of urinalysis testing, and although it is the most expensive, it is often used to confirm positive results of initial tests. Thin-layer chromatography (TLC) was one of the earliest methods developed, but it has been found to be extremely unreliable and is not recommended for use in the criminal or juvenile justice system (Bureau of Justice Assistance, 1990).
Breath analysis is the most commonly used and most cost-effective method of detecting levels of alcohol intoxication. Because alcohol evaporates quickly from urine, urinalysis generally is not used to test for alcohol.
Source: The National Clearinghouse for Alcohol and Drug Information
DHHS Publication No. (SMA) 99-3282
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