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Toxicology Unit Study GuideForensic Science Name:ToxicologyForensic Toxicology: What’s a toxin? A.K.A. PoisonToxin: Neurotoxin: What’s a drug?General: Popular: Clinical: Criminal: Illicit: ExposureChronic- Acute- LD50 -The amount of a substance ______________________ of test subjects exposed to itSubstanceOral LD50 in Rats (mg/kg)DDT87Malathion (old Mosquito spray)885Sugar29,700Caffeine192Strychnine16Salt3,000Arsenic763Poison Dart Frog toxin0.002Vitamin C11,900Ethanol7,060Botulism0.000001Aspirin200Cyanide6.4Dioxin0.020Permethrin (current Mosquito spray)430Mercury1Nicotine50Uptake & Elimination of drugs, alcohol, and toxinsAbsorption: Oxidation: Metabolism: Excretion: Reaction to drugsDependence_________________ dependence: the body changes physiologically; when the user stops taking the substance, the body physically withdraws. Chills, vomiting, pain, hallucinations, etc. can occur.Ex. Highly physically dependent drugs: morphine, heroin, codeine, alcohol, valium, nicotine____________________ dependence: the user keeps taking the substance because it is habitual, and behaviorally ingrained. When the user stops taking the substance, they may crave it, but physically do not feel ill.Ex. Highly psychologically dependent drugs: morphine, heroin, alcohol, amphetamines, cocaine, nicotine*A user may have both types of dependence._____________________: drugs interact with the central nervous system in some fashion. When the body becomes accustomed to the drug, the production of neurotransmitters is often altered. With continued use, to feel the same level of pain relief or euphoria, your body must take in more of the substance than previously used.Effects on the bodyDepressant: Ex. barbiturates, ethyl alcohol, sodium pentothal, valium, inhalants, GHB, Rohypnol, ketamineStimulant: Ex. Cocaine, methamphetamine, nicotine, caffeineNarcotic: Ex. Opium and derivatives, OxyContin* The term narcotic means different things to pharmacologists and lawyersBy law, the term narcotic is used for any illegal substanceBy science, the term is used as defined aboveAnalgesic: Ex. Cocaine, Novocaine, codeine and other opium derivatives, OxyContin, AspirinHallucinogenic: Ex. Marijuana (by default), LSD, mescaline (peyote), psilocybin (shrooms), EcstasyAnabolic steroids: Drug InteractionsSynergism- two drugs act in similar ways Ex. Two stimulantsAntagonism- two drugs act in opposite waysEx. A stimulant and a depressantAddition- two or more drugs that act in similar ways and the effects are additiveEx. Two painkillers that give you twice as much pain reliefPotentiation- two or more drugs act together and the effects are multipliedEx. Two depressants that give you a much quicker reaction or much stronger reaction than either would on their own* None of these are safe interactions!Testing for drugs and/or toxins__________- quick test determines recent use of drugs, alcohol or toxins__________- most accurate test during alcohol, drug, and autopsy testing- can give precise measurements as to the amount used and timeframe__________- long-term timeline of metabolism- 1 cm growth per month__________- quick test determines recent useMethod of uptake____________________: concentrates in stomach, intestines and/or liver ____________________: concentrates in nasal passages and lungs ____________________: concentrates in muscles near injection site, and/or bloodstream Determining cause / manner of death_____________: subject with coronary artery disease takes a stimulant, causing heart attack. C.O.D. is natural (heart attack) but the stimulant is a contributing factor_____________: child ingests cleaning fluid; patient has two conflicting prescriptions_____________: generally a chronic poisoner knows the victim, and intentional poisonings are one of the hardest crimes to solve; chronic exposure over time is hard to detect, while acute gets the job done quickly_____________: intentional overdoses of prescription drugs; carbon monoxide inhalationLevel of Concentration_____________: expected amount in the general population_____________: level that would be prescribed by a doctor_____________: amount would cause illness; vomiting, arrhythmia, fever_____________: amount that consistently causes death; generally the LD50 amountTypes of toxicology testingScreening or Presumptive vs. Confirmatory Drug Testing_____________________ tests are broad-spectrum tests that determine whether or not a wide range of drugs may be present in the given sample. Generally a sample is tested against multiple screening tests to narrow down the list of possible drugs used.________________________ test is used to identify specific drugs in a sample. This is generally done after a subject has tested positive to one or more screening tests49780378318500Toxicology during AutopsyLook for: Irritated tissues- rashes and/or blistering around hands, mouth, noseCharacteristic odors Mees lines—single transverse white bands on nails.Insect activity on a body- insects can take up toxins upon feeding on a body, altering their life-cycle timeline, and storing the metabolites in their bodiesOrder toxicological screensPostmortem concentrations should be done at the scene for comparisonNo realistic calculation of dose can be made from a single measurementSamples taken during autopsyBlood: Urine: Vitreous Humor of Eyes: Bile: Gastric contents: Liver tissue: Brain tissue: Kidney tissue: Hair/nails:Biotoxin Testing__________________________: studying antigen-antibody reactions. Botulism, anthrax, ricin, and other biological agents cause an immune system reaction. By testing whether antibodies react to the blood of a victim, toxicologists know whether that particular antigen was in their system at the time of death.Poison Testing: Heavy metal testing using Reinch Test: dissolve chemical in HCL, add copper; if silvery deposit, could be heavy metal mon PoisonSymptoms / EvidenceCaustic poisons (Lye)Burns around lips / mouthCarbon monoxideRed or pink patches on chest and thighs, unusually bright red lividitySulfuric acidBlack vomitHydrochloric acidGreenish-brown vomitNitric acidYellow vomitPhosphorusCoffee-brown vomit, onion or garlic odorCyanideBurnt almond odorStrychnineRapid rigor mortis, opisthotonos convulsions (arched body) occursInsulinHigh insulin level, low blood sugarAmanita mushroomsExtremely low blood sugarEthylene glycol (antifreeze)Crystals in the kidneysOxalic Acid (raw rhubarb)Burned oral/esophageal tract, low blood-calciumArsenic, mercuryPronounced diarrheaMethyl (wood, moonshine) or isopropyl (rubbing) alcoholNausea and vomiting, unconsciousness, possible blindnessColor Testing: used on suspected drug substances to determine whether they contain specific materialsTestDrugReactantProduct ColorMarquisOpium derivatives (heroin, morphine, hashish, etc.)2% Formaldehyde in sulfuric acidPurpleAmphetamines & methamphetaminesOrange-ish BrownMescalineOrangeDuquenois-LevineMarijuanaVanillin, ethyl alcohol, HCL, chloroform sequencePurpleDillie-KoppanyiBarbituratesCobalt Blue-violetVan UrkLSDHCL, ethyl alcohol, benzylaldehyde sequenceBlue-violetScottCocaineStage 1: cobalt & glycerinBlueStage 2: HCLClear-pink-ishStage 3: chloroformBlueDrug SourcesNaturally OccurringSyntheticSemi-SyntheticMarijuana (THC)AmphetaminesHeroinOpiumBarbituratesLSDCocainePCPPeyote (Mescaline)Prescription drugsMushrooms (Psilocybin)Genetic IdentificationIn addition to color testing, because marijuana, peyote, and mushrooms are biological substances, DNA analysis can be used to identify specific strains and sources of the plants/fungi.Alcohol BasicsEthyl-alcohol is water soluble, so it concentrates in the _____________________________________Liver eliminates ________ of alcohol through metabolism, but ________ is eliminated unchanged via the breath, urine, and sweat. This is how breathalyzer tests work.Alcohol is a ______________, diminishing the central nervous system, but it also targets the autonomic nervous system, which controls involuntary functions, such as breathing. Calculating Blood Alcohol ContentBAC for Male = 0.071 x (% alcohol by volume) x (volume consumed in ounces)Body weight in poundsBAC for Female = 0.085 x (% alcohol by volume) x (volume consumed in ounces)Body weight in poundsProof: the proof on an alcohol label is a measure of alcohol content. Proof is twice the percent alcohol by volume.Ex. Ex. Ex. BAC TimelineAlcohol absorption peaks about 30-90 minutes after consumption. Alcohol burn-off rate is approximately 0.015 per hour.Factors that influence absorption rate_________________; carbohydrate-rich foods slow the absorption of alcohol into the blood stream_________________; each body is different in composition and metabolism rate_________________; the higher the % alcohol by volume, the faster it is absorbed_________________; in general, women absorb alcohol fasterExample 1Pete and Ashley are matching each other drink for drink. They have each had four 1 ounce shots of 40 proof vodka. Pete weighs in at 160 lbs. while Ashley weighs 110 lbs. Calculate the peak B.A.C. for each of them.Example 2Tammy’s peak B.A.C. at 9pm was 0.11. At what time will her B.A.C. reach 0.00?Example 3Ralph (150 lbs.), Marty (175 lbs.) and Phil (230 lbs.) are all drinking from the same bottle of whiskey. Ralph has six 1-ounce shots, Marty has five, and Phil has four. Who is going to have the higher peak B.A.C.?Example 4Britney (120 lbs.) is pulled over at 3 am. She swears that she only had two cans of Coors Light (4.2% alcohol by volume) at 7 pm. She registers a 0.08 on the breathalyzer test. What should her B.A.C. be if her story is true?Alcohol Field TestingPreliminary Breath Test- BreathalyzerAnalyzes alveolar breath (deep breath from the lungs) blown into the deviceMouth alcohol- blowing from the mouth will give a higher alcohol concentration if you have been recently drinking!Blood or urine testing- refusing a PBT in favor of a blood or urine test allows alcohol to soak into the blood stream further, giving a higher reading in most cases. The amount of alcohol in 2,100 milliliters of alveolar breath is equal to the amount of alcohol in 1 milliliter of bloodA chemical reaction takes place in the device, and by measuring the amount of product created, the device determines how much alcohol was present in the breath2K2Cr2O7 + 3C2H5OH + 8H2SO4 2Cr2(SO4)3 + 2K2SO4 + 3CH3COOH + 11H2Opotassium chromate + ethyl alcohol + sulfuric acid chromium sulfate + potassium sulfate + acetic acid + waterField Sobriety TestsPhysiological TestsHorizontal-gaze Nystagmus: When your BAC approaches 0.10, HGN begins before the eyes have moved 45° off centerPupil DilationDivided Attention TasksWalk and TurnOne-leg stand and alphabetNose touch and countAlcohol Reactions and Laws 0.00subjects under 21 years of age- anything other than this is considered an MIP, unless proof of ingestion legally in Canada or Wisconsin. 0.02most people begin feeling the effectsconsidered impaired if over 21 while drivingMIP/DUI when minor registers this level while driving, regardless of legal consumption in Canada/Wisconsin0.025vehicle lock systems will block ignition, and already running vehicles will come to a stop0.04most people feel “buzzed”0.08drunk0.12vomiting may occur0.15 balance is seriously compromised0.17superdrunk * - increased punishments0.30coma is likely0.40possible death0.45most people will stop breathing, causing death ................
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