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Drugs. Overview Dependence and Criminal Activity Types / Classification Methods of Identification Collection and Preservation of Evidence. Drug Defined. a natural or synthetic substance produces physiological /psychological effects in humans / animals. Reasons for Drug Use Today.
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Drugs • Overview • Dependence and Criminal Activity • Types / Classification • Methods of Identification • Collection and Preservation of Evidence
Drug Defined • a natural or synthetic substance • produces physiological /psychological effects • in humans / animals
Reasons for Drug Use Today • Sustain / prolong life • Escape life’s pressures • Enhance performance • Engage in spiritual experiences • End life
Drug Facts • 90 million regularly drink alcohol; 10 million are addicted • 23 million use illicit drugs • More than 75% of evidence processed by crime labs
Drug Dependence • Sustaining/Prolonging Life • Physical Dependence • Psychological Dependence
Physical Dependence • Substances: • Alcohol, narcotics, depressants • Requires prolonged, routine daily doses • Avoiding withdrawal drives dependence • Withdrawal: • Severe physical illness: chills, vomiting, stomach cramps, possible death
Psychological Dependence • Many drugs (see Table Handout) • Hard to define / predict • It’s a “Need” not a “craving” • Withdrawal: headaches, tremors, etc.
Societal Impact of Drugs a Balance between individual and society Pablo Escobar
Routes of Entry • Ingestion • Inhalation • Injection • absorption
Illegal or Illicit Drugs? • Illegal drug = drug that is against the law to have, use or distribute • Illicit drug = a legal drug used in an inappropriate or illegal way
Types of Drugs • Narcotics- CNS depressants • Hallucinogens- altered awareness • Stimulants- increased energy, alertness • Depressants: ease anxiety, induce sleep • Anabolic steroids: promote cell and tissue growth History of Drugs in US
Narcotics: CNS depressants • Analgesics aka pain killers • Opiates: • morphine, heroin, codeine, methadone, • Synthetic opiates: • oxycodone, vicodin, • Psychological and physiologically addictive • Act on opiate receptors in limbic system, brainstem and spinal cord
Hallucinogens: altered awareness • Changes in thought, perception and mood • from plants: • Marihuana, LSD, mecaline • Synthetic • PCP, MDMA • Possibly psychological not physiologically addictive • May act on serotonin (neurotransmitter) receptors in the cortex, disrupting integration
Stimulants: increased energy, alertness • Stimulates CNS activity • include: • Amphetamines, methamphetamine, cocaine, nicotine, caffeine • Psychological not physiologically addictive • Act as key brain neurotransmitters dopamine and norepinephrine
Depressants: ease anxiety, induce sleep • Depresses CNS activity • include: • Barbituates, benzodiazepines, alcohol • Antipsychotic drugs, antianxiety drugs • Psychological and physiologically addictive • Increases brain neurotransmitter activity of GABA
Anabolic steroids • Stimulates cell and tissue growth • Psychological not physiologically addictive • Act similarly to male sex hormone - testosterone
Drug-Control Laws • Careful analysis for type, weight, concentration • Controlled Substance Act (1970) – legal drug classification
Drug Identification • Screening / Presumptive Tests – • quick, easy, cheap • Types • Spot / color tests • Microcrystalline tests • Chromatography • Confirmatory Tests – • Definitive • Types • Spectrophotometry (UV, visible, IR) • Mass Spectroscopy
Presumptive Color Tests • Marquis Test– • Purple opiates • Orange brown amphetamines • Dille-Koppanyl Test • Violet blue barbiturates • Duquenois-Levine Test – • Purple marihuana • Van Urk Test • Blue-purple LSD • Scott Test • Blue cocaine heroin methamphetamine
Microcrystalline Tests • Chemical reagent added to substance on microscope slide • Size and shape of crystals characteristic for certain drugs methamphetamine
Physicians Desk Reference Used to identify manufactured • Pills, tablets, capsules • Updated yearly • Information • Picture • Drug Status • Over the counter, • Prescription, or • Controlled substance
Chromatography • Separates substances in a mixture • mobile and stationary phases • Types • Paper • Thin Layer (TLC) • Gas (GC)
Paper Chromatography • Stationary phase – paper • Mobile Phase – liquid solvent • Capillary action draws solvent and dissolved substance through the stationary phase (paper)
Thin Layer Chromatography • Stationary phase – silica coating on glass • Mobile Phase – liquid solvent • Capillary action draws solvent and dissolved substance through the stationary phase (paper)
Retention Factor Rf • Rf= Dc / Ds • If two Rf’s are close, substances are similar or a match Ds Dc
Gas Chromatography • Stationary phase – solid or viscous liquid • Mobile Phase – inert gas (He, Ne) • Uses retention time not Rf • Shows peak proportional to quantity present
Confirmatory Tests • Identify compounds in Drug Evidence • Tests • Spectrophotometry • Spectroscopy
Spectrophotometry • UV-visible and IR can be used to analyze unknown substances • Substances absorb, reflect or transmit a specific pattern of wavelengths of light • The pattern can be used to ID/quantify unknown substances
UV-visible Spectrophotometry • UV-visible light can be used to identify unknown substances • Identification is not always exact; other substances can have similar patterns
Infrared Spectrophotometry • IR light can be used to identify unknown substances • Absorption pattern is more copmlex • Identification is “chemical fingerprint”
Mass Spectroscopy • Substance bombarded with high energy electrons • Substance ionizes and breaks into smaller fragments • Fragments separate by mass • Fragment pattern is unique to substance
Human Samples for Drug Analysis • Blood • Urine • Hair • Stomach contents • Brain Tissue • Kidney tissue • Spleen tissue
Evidence Collection and Preservation • Prevent loss, cross contamination • Include • Background information • Screening test results