Central Government Laboratory Department of Health and Environment

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1 Central Government Laboratory Department of Health and Environment

2 Overview who we are and what we do What is available and what is protocol for good science Sample collection Screening Tests Confirmation Testing Tampering techniques Drug Detection window Submission of Specimens to CGL

3 The Central Government Laboratory (CGL) is equipped with highly knowledgeable and skilled scientist in the area of: Toxicology Drug Chemistry Biology Microbiology Forensic and Public Health issues CGL is the only lab on Island with equipment and expertise to confirm drug use. Authorised analyst under the Misuse of Drugs Act 1972, Road Traffic Act 1947 and work under various other Acts (e.g. PACE Act 2005 and Pharm and Poisons Act 1979)

4 Reasons for Drug testing Random e.g. probation, drug court, work place, sports Pre-Employment DUI/accidents (alcohol and drugs) Equipment used Immunoassay technique Dipstick tests are frequently used but many drawbacks (cross reaction, false neg/pos) All positives should be confirmed (only done at CGL) Types of Specimens Hair Saliva, Sweat, Fingerprints Blood Urine

5 Direct Observation of Urine Collection Supervision required Jackets/coats should be removed, pockets emptied Subject should wash hands before providing specimen. Check the sample temperature, colour, odor, particulate matter. Label sample correctly Make sure it is random, unannounced, unpredictable

6 Usually immunologically based Provide a preliminary result only All screening test manufacturers state the following (or similar) provides a preliminary result only. A more specific chemical method must be used to obtain a confirmed analytical result. E.g. Gas Chromatography- Mass Spectrometry (GC-MS). Clinical consideration and professional judgment should be applied to any drug of abuse test result

7 On-site screening devices (rapid tests) Can be convenient Are relatively cheap BUT All drug screening devices are not the same Subjective reading Usually no quality controls Need to check expiration dates, storage conditions

8 Performed in CGL on clinical analyzer Reliable and accurate Drug calibrations daily Quality control samples used Reports as positive or negative Any positive drug screen result is repeated with the original sample and confirmed.

9 Drugs SAMSHA levels (CGL follows in general) On site screening tests Medtox Sure Screen Cannabinoids 50 ng/ml Premier Dip Cocaine (metabolite) Opiates 150 ng/ml (previously 300ng/ml) 2000 ng/ml (CGL uses 300 ng/ml) or or 2000 Ecstasy (MDMA) 500 ng/ml 500 Amphetamine/ Methamphetamine 500 ng/ml (previously 1000 ng/ml) SAMSHA = Substance Abuse and Mental Health Services Administration 300/

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11 Screening tests provide preliminary results only They test for groups of drugs Opiates a positive opiate test could be due to any of the following drugs, Heroin (diamorphine), Morphine, Codeine, Dihydrocodeine, Oxycodone, Pholcodeine or others. Some of these are prescription or over the counter drugs.

12 Because screening tests are based on a antigen(drug) antibody reaction, cross reactions with drugs or metabolites with similar structure can occur; for some cross reactions the mechanism can be unknown Cannabinoids some screening tests give a false positive with the HIV drug Sustiva (efavirenz). This is also found in the combination antiretroviral, Atripla. Amphetamines/Ecstasy these screening tests cross react with a variety of over-the counter medications containing for example ephedrine, pseudoephedrine, phentermine.

13 Confirms the presence of a specific drug or metabolite. Confirmed by Gas Chromatography- Mass Spectrometry Confirmation should be performed on all urine specimens Legal use Workplace disciplinary purposes seriously impacts the subject/client where data is to be used / published

14 Drug/metabolite SAMSHA Confirmation cut-off level Cocaine (BZE) metabolite Carboxy-THC Amphetamine Methamphetamine Ecstasy 100ng/ml (previously 150ng/ml) 15ng/ml 250ng/ml (previously 500ng/ml for Amphetamine/Methamphetamine) results are reported as positive or negative depending on if the drug levels are above or below the cut-off value for that particular drug.

15 Drug levels confirmed are NOT reported Reported as positive or negative Urine Drug Concentrations only indicates past drug use

16 Dilution- most common form of tampering Most Commonly occurs before testing large quantities of fluids consumed Cleansing products to clean system of drugs eg Gold Seal, Clean n Clear Flushing can be detected by measuring the creatinine Masking with certain OTC drugs Water can also be added to the urine after collection should not occur if supervised. If not supervised, can disable the hot water tap any diluted urine would then be cooler than body temperature (use of temperature strips on urine containers)

17 Gives an indication of the dilution of a urine specimen Creatinine is a breakdown product of creatine in muscle, and is produced by the body at a relatively constant rate. All specimens submitted to CGL are tested for creatinine Urine samples with a creatinine level of less than 20mg/dl are considered dilute. CGL will still perform and report the screening still can be positive for drugs Specimens with a creatinine level of less than 5mg/dl are considered to be substituted or not consistant with normal human urine and are unsuitable for analysis ie not urine. Other similar liquids eg apple juice are sometimes substituted for urine

18 Added after collection of specimen importance of good supervision Substance added to mask the presence of drugs Adulterants that can change ph eg vinegar, bleach, ammonia. Nitrites eg Klear, Oxidising agents eg peroxidase (Stealth), dichromate (Urine Luck) Glutaraldehyde (Urinaid) Can affect screening tests New types/products constantly being introduced - Search on-line for beat drug test etc Specimen validity testing available with some on-site test devices (rapid tests)

19 The Drug Detection window refers to the length of time following the last drug use that the urine sample continues to produce positive test results. Many factors influence the detection window Dose of drug Duration and frequency of use Rate of metabolism Sensitivity of test Specificity of test

20 Based on standard methods and cut-off levels (SAMSHA guidelines) Cocaine 1-3 days Opiates 1-4 days Amphetamines/Ecstasy 2-4 days Cannabinoids not exact answer

21 Before you can be legally tested, you must complete and sign a Consent Form, which requires that you disclose all medications taken recently. Can send urine specimen directly to CGL for testing. Also can perform on-site screening first. If positive, this original specimen can be sent to CGL we re-screen, then if positive on our equipment, perform confirmation testing. If on-site screening is performed and you get a negative result, but behavior or other information indicates recent drug use, specimen can be sent to CGL for re-screening. For sending to CGL fill in information on security seal and apply over top of specimen container Complete submission / chain of custody form Store in secure refrigerator until specimen can be transported to laboratory as soon as possible but no more than 1 week after collection.

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