Slide 1. Slide 2. Slide 3. Definitions. Definitions. Drug-Facilitated Sexual Assault

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1 Slide 1 Drug-Facilitated Sexual Assault Prepared by Matthew Stillwell, M.S., M.A., ABFT-FTS on behalf of the Society of Forensic Toxicologists Drug Facilitated Sexual Assault Committee & the Oklahoma State Bureau of Investigation Toxicology Unit Slide 2 Definitions Sexual Assault - Forced, coerced or pressured sexual contact. Acquaintance Rape - Nonconsensual sexual contact with someone known to you. Date Rape - A type of acquaintance rape, whereby nonconsensual sex takes place between two people in a relationship. Drug-Facilitated Sexual Assault - Use of a chemical agent to procure sexual contact. 2 Slide 3 Definitions Legal definitions of rape vary Offense whereby a person is subjected to nonconsensual sexual acts while they are incapacitated or unconscious due to the effects of alcohol and/or drugs and are therefore prevented from resisting and/or are unable to consent M. LeBeau et. al. Drug Facilitated Sexual Assault: A Forensic Handbook, Academic Press,

2 Slide 4 Types of Scenarios Surreptitious administration slipping a mickey Voluntary administration Administration under fraudulent conditions (the nature and/or effects of the drug were misrepresented) Combination of the above 4 Slide 5 Common Drug Effects* Confusion Dizziness Drowsiness Psychomotor impairment Impaired memory Impaired judgment * Effects vary with drug(s) used Reduced inhibitions Slurred speech Weakness rubbery legs Unsteadiness Powerlessness Southern Medical Journal 93(6): (2000) 5 Slide 6 Description of Chemical Submission Agents Some are potent, fast-acting drugs with amnesic properties Some are CNS depressants that impair consciousness, memory, lower inhibitions, alter judgment Some may produce an anesthetic-type effect, unarousable sleep, out of body experience, powerlessness, paralysis or inability to move 6

3 Slide 7 Public Perception of Date Rape Drugs Date rape drugs reported by the media: Rohypnol (Flunitrazepam, Roofies) GHB (Easy Lay, Good hormones at bedtime) Epidemiological studies in alleged DFSA cases have not confirmed that GHB and Rohypnol are the most popular drugs used 7 Slide 8 Drugs Used More than 20 substances have been associated with drug-facilitated sexual assault Benzodiazepines Barbiturates Antihistamines Muscle relaxants Stimulants Depressants Tranquilizers Narcotics Antidepressants Psychedelics Hypnotics Anticonvulsants J. Forens. Sci. 44(1): (1999) 8 Slide 9 Specific Drugs Associated With Sexual Assault Alprazolam Amphetamine Barbiturates Carisoprodol Chloral hydrate Chlordiazepoxide Clonazepam Cocaine Cyclobenzaprine Diazepam Diphenhydramine Ethanol Flurazepam Flunitrazepam GHB Ketamine Lorazepam Marijuana Meprobamate Methamphetamine Methylenedioxymethamphetamine Opiates Scopolamine Triazolam Midazolam 9

4 Slide 10 Potential DFSA Agents.. Illicit Drugs Therapeutic Drugs Over-the-counter (OTC) Drugs Herbal/Dietary Supplements 10 Slide 11 Ethanol and DFSA Easy to obtain Can be administered in a social environment without suspicion Ethanol is the drug most commonly associated with rape Causes decreased inhibitions, impaired perceptions, loss of consciousness and memory Prosecution may be unlikely 11 Slide 12 Pharmacology of Ethanol Rapidly absorbed into circulation Widely distributed in body water and central nervous system (CNS) Rapidly eliminated at constant rate On average 0.015g/100mL/h Detection times in blood and urine vary depending on dose 12

5 Slide 13 Benzodiazepines and DFSA Most commonly encountered prescribed drugs in forensic analysis One of the most widely prescribed drug classes in the world Anxiolytics, muscle relaxants, sedative/hypnotics, anesthetic adjuncts, anticonvulsants, panic disorders, obsessive-compulsive disorders Approximately 20 benzodiazepines approved in the U.S. Principles of Forensic Toxicology, AACC Press, 2 nd Ed. 2003, Ed. B. Levine. 13 Slide 14 Common Benzodiazepines Alprazolam (Xanax ) Chlordiazepoxide (Librium ) Clonazepam (Klonopin ) Diazepam (Valium ) Flurazepam (Dalmane ) Lorazepam (Ativan ) Temazepam (Restoril ) Triazolam (Halcion ) 14 Slide 15 Benzodiazepine Misconception Common Misconception: ONLY flunitrazepam (Rohypnol ) is capable of being a date rape drug among the benzodiazepines FACT: ALL benzodiazepines are able to exert the same or similar effects ***The DOSE determines the effect*** 15

6 Slide 16 Flunitrazepam (Rohypnol ) MORE potent than diazepam (Valium ) Onset minutes, duration 2-12 hours* Passivity, disinhibition, lack of resistance, muscle relaxation, slurred speech, confusion, ataxia Anterograde amnesia Soluble in alcohol, colorless, odorless, tasteless Requires sensitive methods of analysis * RC Baselt, Drug Effects on Psychomotor Performance, Biomedical Publications, Slide 17 Flunitrazepam (Rohypnol ) Sedative/anesthetic adjunct in 80 countries world-wide Low dose (1-2 mg) Not approved for use in the U.S. Old tablets: - Single score on one side - 1 or 2 and Roche on other side New tablets: - Olive green color and single score - Blue dye released when dissolved 17 Slide 18 Gamma Hydroxybutyrate (GHB) Naturally occurring neuromodulator Profound CNS depressant Effects minutes, duration hours Euphoria, disinhibition, nausea, vomiting, respiratory depression, Out of body experience, coma Anterograde amnesia Large doses (2-4g), water soluble, easily disguised in flavorful beverages Not readily detected Window of detection 6-8 h (blood) 12 h (urine) Xyrem (sodium oxybate) was approved by the FDA in Treatment of cataplexy associated with narcolepsy RC Baselt, Disposition of Toxic Drugs and Chemicals in Man, Biomedical Publications,

7 Slide 19 GHB and DFSA Easily obtained Can be synthesized from industrial cleaners and household items Fast acting sedative properties Memory effects Rapidly eliminates Difficult to detect Many labs don t test for GHB routinely Naturally occurring Photo courtesy of OSBI Requires careful interpretation of results GHB/GBL seized in Canadian County 19 Slide 20 Hallucinogens Ketamine (Special K, Super Acid, Bump) Phencyclidine (PCP) Marijuana MDMA (Ecstasy) LSD Others (mushrooms, scopolamine etc) 20 Slide 21 Hallucinogens and DFSA Dissociative effects Sedative effects Semi-consciousness Many are popular recreational drugs (marijuana, MDMA, ketamine) Victims may voluntarily administer drug(s) Hallucinations, dizziness, impaired judgment, nausea, irrational behavior 21

8 Slide 22 Marijuana and DFSA Sedative properties Hallucinogenic properties Impairs memory Impairs cognition Popular recreational drug Easy to obtain Voluntarily consumed Additive effects with ethanol 22 Slide 23 Other Drugs and DFSA Potentially hundreds of DFSA agents Opiates, barbiturates, antihistamines, muscle relaxants, sedatives, antidepressants, veterinary/human anesthetics, inhalants. Herbals and dietary supplements? 23 Slide 24 Specimen Collection Delays in collection of blood and urine may influence the toxicology results and may adversely affect the prosecutorial outcome of a DFSA Take immediate action to preserve biological evidence Urge the victim not to urinate prior to the evidentiary exam 24

9 Slide 25 Types of Toxicological Evidence to Collect Blood Pharmacological interpretation Shorter detection time Collect within 24 hrs of suspected ingestion of agent Collect ~ 10-20mL Preserve with sodium fluoride & potassium oxalate (gray-top tube) Store refrigerated Urine Limited interpretation Longer detection times Collected within 96 hrs of suspected ingestion of agent Collect ~ 100 ml Store refrigerated J. Forens. Sci. 44(1): (1999) 25 Slide 26 Documentation for the Toxicologist Time of alleged assault Time of alleged drug use What (recreational, Rx, OTC) drugs were used (if known) and list all drugs taken during the past two weeks. Time of forensic examination (specimen collection) Time between incident and specimen collection Was the first void of urine since the incident collected What were the effects (consciousness, neurological, psychophysical, memory, gastrointestinal, genitourinary) How much alcohol (if any) was consumed; and time frame Was the individual unconscious and for how long Does the individual have pre-existing health issues 26 Slide 27 Toxicology Analysis Forensic laboratory that is familiar with DFSA and has necessary resources to detect substances commonly used Low immunoassay cut-off concentrations Sensitive confirmatory analyses, e.g. GC/MS that are capable of detecting <10 ng/ml of drug May require specialized procedures or equipment (e.g. Chemical ionization, tandem mass spectrometry) 27

10 Slide 28 Pharmacology Basics Two Subdivisions Pharmacokinetics What the body does to the drug Absorption Distribution Metabolism Pharmacodynamics What the drug does to the body Receptor Binding Signal Transduction Biological Effect Excretion 28 Slide 29 Pharmacology Basics Fate of drug in body 29 Slide 30 Pharmacology Basics Route for administration -Determination of Onset of Effect- Intravenous seconds Inhalation Sublingual Intramuscular Subcutaneous Rectal Ingestion 2-3 minutes 3-5 minutes minutes 5-30 minutes 5-30 minutes minutes 30

11 Drug Concentration Drug Concentration Slide 31 Pharmacology Basics Drug Profile for Blood and Urine URINE BLOOD Time 31 Slide 32 Pharmacology Basics The Half-Life Concept Example: Drug T 1/2 = 5 hrs, with C ng/ml Time (hrs) Drug Conc (ng/ml) (100%) 1X T 1/2 = 5 50 (50%) 2X T 1/2 = 5 25 (25%) 3X T 1/2 = (12.5%) 4X T 1/2 = (6.25%) 5X T 1/2 = (3%) 6X T 1/2 = (1.5%) 7X T 1/2 = (0.75%) Commonly accepted that drugs are eliminated in 6 to 7 half-lives (no longer detectable). Significant drug effects on the CNS are generally not apparent after 5 half-lives. 32 Slide 33 Pharmacology Basics Why Were no Drugs Detected? URINE 1. No exposure 2. specimen collected too late 3. Below detectable limit BLOOD Limit of Detection Detection Time in Blood Detection Time in Urine Time 33

12 Slide 34 Pharmacokinetic Properties of Selected Depressants D ru g D o se (m g ) D u ratio n (h ) H alf L ife (h ) D etectio n T im e (h ) B lo o d U rin e A lp razo lam h 72h C lo n azep am h 168h L o razep am h 72-96h T riazo lam h 48h F lu n itrazep am h 72h F lu razep am h d ays D ip h en h yd ram in e h 96h G H B h 12h D iazep am h d ays K. Janzen, Bulletin of the International Association of Forensic Toxicologists. 34 Slide 35 Toxicological Analysis Many labs do not test for GHB, flunitrazepam metabolites and other low dose benzodiazepines Lab must be able to detect SINGLE DOSE levels of drugs Immunoassay (IA) screening for common drugs of abuse is not sufficient Immunoassay cut-off concentrations must be sufficiently low Not all drugs can be detected using common drug screens 35 Slide 36 Importance of Immunoassay Cut-off Concentrations Forensic* SAMHSA Amphetamines ng/ml Cannabinoids ng/ml Cocaine ng/ml Opiates ng/ml PCP ng/ml * Vary by institution Amphetamines 1000 ng/ml Cannabinoids 50 ng/ml Cocaine 300 ng/ml Opiates 2000 ng/ml PCP 25 ng/ml 36

13 Slide 37 Importance of Immunoassay Cut-off Concentrations SAMHSA (Substance Abuse and Mental Health Services Administration) cutoff concentrations designed for workplace drug testing. They were not intended for criminal casework. On-site or point-of-care devices used in some hospital/clinical labs may not be effective Cutoff concentrations are often too high for DFSA casework and the scope of testing is often too limited 37 Slide 38 Interpretation of Results Blood Positive - Good indicator of recent exposure (hrs) Negative - No exposure or specimen collected too late Urine Positive - Good indicator of exposure (days) Negative - No exposure or specimen collected too late Negative toxicology does not necessarily exclude the role of drugs, especially if there was a delay in specimen collection 38 Slide 39 Any Questions? 39