Forensic ToxicologyForensic Toxicology

ToxicologistToxicologist

An individual charged with the An individual charged with the responsibility of detecting and identifying responsibility of detecting and identifying the presence of drugs and poisons in the presence of drugs and poisons in body fluids, tissues, and organsbody fluids, tissues, and organs

Not only for death Not only for death investigationsinvestigations

Hospitals labs for drug overdosesHospitals labs for drug overdoses Blood tests on children for exposure to Blood tests on children for exposure to

lead lead Examine urine of addictsExamine urine of addicts

ToxinsToxins

Any material exerting life threatening Any material exerting life threatening effects upon a living organismeffects upon a living organism

A toxin is a poisonous substance A toxin is a poisonous substance produced by a living organism produced by a living organism

Poisons are a subcategory of toxinsPoisons are a subcategory of toxins

Toxins vs PoisonsToxins vs Poisons

May enter the body May enter the body in different ways.in different ways.

Work in low Work in low quantities or low quantities or low levelslevels

Easy to detectEasy to detect If treatment is early, If treatment is early,

the person can be the person can be saved.saved.

Normally enter in a Normally enter in a single massive dosesingle massive dose

Normally are found in Normally are found in huge doses.huge doses.

Hard to detect Hard to detect People often die People often die

because the reason because the reason for illness is not for illness is not detected soon detected soon enough.enough.

Dose-Response Dose-Response RelationshipRelationship

Relationship between the amount of a Relationship between the amount of a substance that a human would be substance that a human would be exposed to and the relationship to their exposed to and the relationship to their body after exposure. body after exposure.

Lethal DoseLethal Dose

Lethal dose is the dose taken that would Lethal dose is the dose taken that would cause death to the organismcause death to the organism

To determine the Lethal Dose scientists To determine the Lethal Dose scientists test two different animals and two test two different animals and two different methods of exposure (one being different methods of exposure (one being the way humans would take the the way humans would take the substance)substance)

Lethal DoseLethal Dose

In a lethal dose study, scientists will In a lethal dose study, scientists will study how much will have to be given to study how much will have to be given to the two different animals in order to the two different animals in order to cause death.cause death.

Animals in these studies normally die Animals in these studies normally die within 14 days and scientists can take within 14 days and scientists can take their results from these tests and relate their results from these tests and relate them to human beings.them to human beings.

Most heavily abused Most heavily abused substance is legal!!substance is legal!!

Ethyl AlcoholEthyl Alcohol 40% traffic deaths40% traffic deaths 17,500 fatalities a year17,500 fatalities a year 2 million injuries a year2 million injuries a year

Toxicology of AlcoholToxicology of Alcohol

Metabolism- the transformation of a Metabolism- the transformation of a chemical in the body to other chemicals chemical in the body to other chemicals for facilitating its elimination from the for facilitating its elimination from the bodybody

3 steps3 steps AbsorptionAbsorption DistributionDistribution EliminationElimination

AbsorptionAbsorption

Alcohol appears in the blood minutes Alcohol appears in the blood minutes after consumption and increases in after consumption and increases in concentration while it is being absorbed concentration while it is being absorbed from the stomach and small intestine into from the stomach and small intestine into the bloodstream.the bloodstream.

Absorption= the passage of a substance Absorption= the passage of a substance across the wall of the stomach and small across the wall of the stomach and small intestine into the blood streamintestine into the blood stream

What affects rate of What affects rate of absorptionabsorption

How long it takes to consume a beverageHow long it takes to consume a beverage Alcohol content of beverage (proof)Alcohol content of beverage (proof) The amount consumedThe amount consumed Food present in stomachFood present in stomach

Distribution of AlcoholDistribution of Alcohol

BloodstreamBloodstream

BAC tests performed BAC tests performed

EliminationElimination

Oxidation- 95-98% of the alcohol Oxidation- 95-98% of the alcohol undergoes this chemical process which undergoes this chemical process which converts alcohol to carbon dioxide and converts alcohol to carbon dioxide and water. Occurs in liver.water. Occurs in liver.

Elimination- 2-5% is excreted by Elimination- 2-5% is excreted by perspiration, urination, and breathingperspiration, urination, and breathing

Breathalyzer TestBreathalyzer Test

The amount of alcohol exhaled in the The amount of alcohol exhaled in the breath is in direct proportion to the breath is in direct proportion to the concentration of alcohol in the blood.concentration of alcohol in the blood.

Elimination varies with Elimination varies with individualindividual

WeightWeight Muscle tone or physical conditionMuscle tone or physical condition History with drug (tolerance)History with drug (tolerance) MetabolismMetabolism AgeAge

Blood Alcohol Blood Alcohol concentrationconcentration

Blood Alcohol ContentBlood Alcohol Content

Most accurate testMost accurate test Requires bloodRequires blood

AbsorptionAbsorption

20% absorbed by the stomach20% absorbed by the stomach 80% by small intestines80% by small intestines All alcohol is broken down by liverAll alcohol is broken down by liver

Arteries will have a higher BAC than Arteries will have a higher BAC than veins during absorptionveins during absorption

Blood tests retrieve blood from veinsBlood tests retrieve blood from veins

Testing for intoxicationTesting for intoxication

BAC not convenient for traffic officersBAC not convenient for traffic officers Breath testing performedBreath testing performed BreathalyzerBreathalyzer

Developed 1954 by R.F. BorkensteinDeveloped 1954 by R.F. Borkenstein Uses chemicals to detect BACUses chemicals to detect BAC

Fuel Cell detectorFuel Cell detector

A chemical reaction involving alcohol A chemical reaction involving alcohol produces electricityproduces electricity

Will give officer a digital readout of BACWill give officer a digital readout of BAC

Errors in detectionErrors in detection

Police are supposed to ensure no foreign Police are supposed to ensure no foreign material is in mouth for 15 minutes before material is in mouth for 15 minutes before testtest

Regurgitation (throwing up) Regurgitation (throwing up) BelchingBelching Recent DrinkingRecent Drinking Gargling with an alcohol based Gargling with an alcohol based

mouthwashmouthwash

Field sobriety testsField sobriety tests

Deal with physical impairmentsDeal with physical impairments Stand on one legStand on one leg Walk straight lineWalk straight line Horizontal gaze nystagmusHorizontal gaze nystagmus Walk heel to toeWalk heel to toe

Alcohol and the lawAlcohol and the law

1992 US Department of Transportation 1992 US Department of Transportation (DOT) required states adopt 0.08% BAC(DOT) required states adopt 0.08% BAC

Made federal law in 2000Made federal law in 2000 If an individual exceeds .08% they are If an individual exceeds .08% they are

deemed “intoxicated”deemed “intoxicated” In 2003 states that did not abide with this In 2003 states that did not abide with this

law lost federal funding for highway law lost federal funding for highway constructionconstruction

Alcohol and the lawAlcohol and the law Commercial drivers such as bus or 18 Commercial drivers such as bus or 18

wheelers must not exceed .04 % BACwheelers must not exceed .04 % BAC

Is it constitutional??Is it constitutional??

55thth amendment states that you have the amendment states that you have the right to not incriminate yourselfright to not incriminate yourself

Driving is a privilege not a “right” so they Driving is a privilege not a “right” so they may take away your license for refusing may take away your license for refusing to test (6 months-12 months)to test (6 months-12 months)

Role of the ToxicologistRole of the Toxicologist

Generally there are few signs that Generally there are few signs that indicate what type of poison in systemindicate what type of poison in system Clues arise fromClues arise from

Medicine bottlesMedicine bottles Household chemicalsHousehold chemicals Postmortem pathological examinationPostmortem pathological examination

Toxicologist mustToxicologist must

Work with nanograms and micrograms of Work with nanograms and micrograms of specimen due to absorption of bodyspecimen due to absorption of body

Pure samples are easier to analyzePure samples are easier to analyze The body metabolizes each substance The body metabolizes each substance

differentlydifferently Example- heroin is almost immediately Example- heroin is almost immediately

broken down to morphine in the bodybroken down to morphine in the body Toxicity levels vary by individualToxicity levels vary by individual

Toxicologist handlesToxicologist handles

Blood (a minimum of 10 ml required)Blood (a minimum of 10 ml required) UrineUrine

90% of the drugs 90% of the drugs encountered in a toxicology encountered in a toxicology lab are:lab are:

CocaineCocaine AlcoholAlcohol MarijuanaMarijuana

Acid/Base TestsAcid/Base Tests

Toxicologist can extract acidic drugs from Toxicologist can extract acidic drugs from acidified water using chloroformacidified water using chloroform

Basic drugs can be extracted using basic Basic drugs can be extracted using basic water solutions and organic solventswater solutions and organic solvents

DrugsDrugs

AcidicAcidic BarbituatesBarbituates AspirinAspirin

BasicBasic PhencyclidinePhencyclidine MethadoneMethadone AmphetaminesAmphetamines CocaineCocaine

Famous casesFamous cases

1982 Tylenol was tampered with in 1982 Tylenol was tampered with in Chicago. Someone opened up the gels Chicago. Someone opened up the gels capsules and replaced drug with capsules and replaced drug with potassium cyannidepotassium cyannide

7 deaths7 deaths $100,000 reward from tylenol for $100,000 reward from tylenol for

information information

Toxicology of hairToxicology of hair

Most drugs leave bloodstream within 24 Most drugs leave bloodstream within 24 hours. Urine tests are accurate up to 72 hours. Urine tests are accurate up to 72 hours on averagehours on average

Drugs present in blood diffuse through Drugs present in blood diffuse through capillary walls into the base of hair and capillary walls into the base of hair and become permanently entrapped in the become permanently entrapped in the protein structure protein structure

Toxicology of hairToxicology of hair

As the hair grows, the drugs location on As the hair grows, the drugs location on the hair shaft becomes a historical the hair shaft becomes a historical marker for drug intakemarker for drug intake

Human hair grows an average of 1 cm a Human hair grows an average of 1 cm a monthmonth

Nondrug poisonsNondrug poisons

Heavy metals- Substance is placed in HCl with Heavy metals- Substance is placed in HCl with a copper strip. Silver or dark coating means a copper strip. Silver or dark coating means presence of heavy metal. Confirmation tests presence of heavy metal. Confirmation tests necessary.necessary. ArsenicArsenic BismuthBismuth LeadLead AntimonyAntimony MercuryMercury ThalliumThallium

Nondrug poisonsNondrug poisons

Carbon Monoxide (CO)Carbon Monoxide (CO) Suicide by car- usually a vacuum hose or Suicide by car- usually a vacuum hose or

garden hose in tailpipe to stream gas into garden hose in tailpipe to stream gas into car. 5-10 minutes in single car garage with car. 5-10 minutes in single car garage with car running is sufficient for deathcar running is sufficient for death

Also seen in fires.Also seen in fires.

Drug Recognition ExpertsDrug Recognition Experts

3-5 month Training3-5 month Training Can suggest if victim/offender exhibited Can suggest if victim/offender exhibited

behaviors associated with:behaviors associated with: CNS depressantsCNS depressants CNS stimulantsCNS stimulants HallucinogensHallucinogens Dissociative Anesthetics (phencyclidine)Dissociative Anesthetics (phencyclidine) InhalantsInhalants Narcotic AnalgesicsNarcotic Analgesics CannabisCannabis