forensic toxicology analytical toxicology fall 2007 analytical toxicology fall 2007
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Forensic ToxicologyForensic Toxicology
Analytical Toxicology
Fall 2007
Analytical Toxicology
Fall 2007
Forensic ToxicologyForensic Toxicology
Toxicology is defined as the study of the adverse effects of chemicals on living organisms.
Forensic toxicology is defined as the application of toxicology for the purposes of the law.
Forensic ToxicologyForensic ToxicologyPostmortem forensic
toxicology.
Human performance toxicology.
Forensic drug testing.
HistoryHistoryAncient Egyptians and Grecians
reported poisonings due to herbs, plants and food.
Opium, arsenic and hydrocyanic acid were used throughout Europe during the middle ages.
HistoryHistory Philippus Theophrastus Aureolus
Bombastus von Hohenheim (or Paracelsus) observed that any substance could be a poison, depending on its dose
“ What is there that is not poison? All things are poison and nothing without poison. Solely the dose determines that a thing is not a poison”
HistoryHistory In 1814, M.J.B. Orfila, the
chairman of the legal medicine department at the Sorbonne in France, published a book entitled Traite des poisons ou Toxicologie Generale.
HistoryHistory In 1851, Stas developed the first
effective method for extracting alkaloids from biological specimens.
This was modified several years later by Otto, which enabled the isolation of purer alkaloid substances.
HistoryHistory In the U.S., forensic toxicology did
not develop until the early 20th century.
Dr. Alexander Gettler is considered this country’s first forensic toxicologist.
Postmortem Forensic Toxicology
Postmortem Forensic Toxicology
Suspected drug intoxication cases Homicides Arson fire deaths Motor vehicle fatalities Deaths due to natural causes
Postmortem Forensic Toxicology
Postmortem Forensic Toxicology
Death Investigations
Coroner
Medical Examiner
Postmortem Forensic Toxicology
Postmortem Forensic Toxicology
Specimens Blood – from the heart and from the
femoral or jugular veins Vitreous humor Urine Bile Liver Other – lung, spleen, stomach contents or
brain
Postmortem Forensic Toxicology
Postmortem Forensic Toxicology
Analytical Process Separation
Identification
Confirmation
Quantitation
Postmortem Forensic Toxicology
Postmortem Forensic Toxicology
Analytes Volatiles (Carbon Monoxide,
Cyanide, and Alcohols)
Drugs
Metals
AC
ET
AL
DE
HY
DE
(1.
414
min
.)E
HT
AN
OL
(1.
787
min
.)
2-P
RO
PA
NO
L (
2.80
4 m
in.)
ME
K(I
ST
D)
(5.5
84 m
in.)
AC
ET
ON
E (
2.46
2 m
in.)
0 6
Postmortem Forensic Toxicology
Postmortem Forensic Toxicology
Drugs One Comprehensive Approach:
Postmortem Forensic Toxicology
Postmortem Forensic Toxicology
Metals Aluminum Arsenic Iron Mercury Lead Thallium
Postmortem Forensic Toxicology
Postmortem Forensic Toxicology
Metals (continued) Analysis
ColorimetricGraphite Furnace Atomic Absorption
Spectrometry Inductively Coupled Plasma – Mass
SpectrometryNeutron Activation Spectrometry
Human Performance Toxicology
Human Performance Toxicology
Human performance toxicology is also referred to as behavioral toxicology.
It is the study of human performance under the influence of drugs.
Human Performance Toxicology
Human Performance Toxicology
Ethanol and driving
History
Behavioral effects
Specimens
Ethanol ToxicologyEthanol Toxicology
Types of alcohol
Ethanol (ethyl alcohol)
Methanol (methyl alcohol)
Isopropanol
Ethylene glycol
Ethanol ToxicologyEthanol Toxicology
Ethanol production Fermentation of sugar or starch
Can only achieve 20% ethanol
DistillationDistilled alcoholic beverages are usually
40 to 50% ethanol by volume (80-100 proof)
Ethanol PharmacokineticsEthanol Pharmacokinetics
Absorption Means of absorption
Dermal Inhalation IVOral
Gastrointestinal tract Presence of food.
Ethanol PharmacokineticsEthanol Pharmacokinetics Distribution
Gastrointestinal tract Portal vein Liver Heart Lung Heart Body
Ethanol PharmacokineticsEthanol Pharmacokinetics
Elimination
5-10% in the urine
Saliva, expired air and sweat
Liver (enzymatic oxidation to acetaldehyde, acetic acid and carbon dioxide)
Ethanol Effects on the BodyEthanol Effects on the Body
Cardiovascular system
Central nervous system
Gastrointestinal tract
Ethanol Effects on the BodyEthanol Effects on the Body
Kidney
Liver
Breath Ethanol TestingBreath Ethanol Testing
Theory
Henry’s law
Ethanol in breath Vs ethanol in blood
2100 to 1 ratio
2300 to 1 ratio
Breath Ethanol TestingBreath Ethanol Testing
Types of analyzers Chemical
Reaction of ethanol with potassium dichromate/sulfuric acid solution
Colored solution that results is measured spectrophotometrically
IR spectrophotometry Electrochemical oxidation - fuel cell
Breath Ethanol TestingBreath Ethanol Testing
IR Spectrophotometry Based on absorbance of light by the
ethanol molecule Mainstay in evidential breath testing
devices
Electrochemical Oxidation Oxidation of ethanol to acetic acid Also used in evidential breath testing
Blood Ethanol TestingBlood Ethanol Testing
Chemical
Screening
Quantitative
Disadvantage - aldehydes and ketones will interfere with the test
Blood Ethanol TestingBlood Ethanol Testing Enzymatic
Conversion of NAD to NADH by ethanol (serum, urine and whole blood)Measured spectrophotometrically at
340 nm
Same reaction with a blue dye (thiazoyl blue) (serum, urine, fresh blood and postmortem blood)Measured with a fluorometer
Blood Ethanol TestingBlood Ethanol Testing
Gas Chromatography Can measure ethanol in a wide range
of specimens Can distinguish ethanol from other
alcohols, aldehydes and ketones Two common methods
Head spaceDirect injection
AC
ET
AL
DE
HY
DE
(1.
414
min
.)E
HT
AN
OL
(1.
787
min
.)
2-P
RO
PA
NO
L (
2.80
4 m
in.)
ME
K(I
ST
D)
(5.5
84 m
in.)
AC
ET
ON
E (
2.46
2 m
in.)
0 6
Assessment of Ethanol Impairment
Assessment of Ethanol Impairment
In a British study: Detectable deterioration of drivers at
between 30 – 50 mg/dL Obvious deterioration observed at between
60 – 100 mg/dL
In another British study: Pilots exhibited impairment at 40 mg/dL
Assessment of Ethanol Impairment
Assessment of Ethanol Impairment
Blood alcohol concentration: 10-50 mg/dL: Impairment detectable
by special tests 30-120 mg/dL: Beginning of
sensory-motor impairment 90-250 mg/dL: Sensory-motor
incoordination; impaired balance 180-400 mg/dL: Increased muscular
incoordination; apathy; lethargy
Assessment of Ethanol Impairment
Assessment of Ethanol Impairment
Blood alcohol concentration: 250-400 mg/dL: Impaired
consciousness; sleep; stupor 350-500 mg/dL: Complete
unconsciousness; coma 450 and greater mg/dL: Death from
respiratory arrest
Stages of Acute Alcohol Intoxication*
*Reprinted by permission of K.M. Dubowski, 1997.
Death from respiratory arrestDeath0.45+
Possible deathImpairment of circulation and respirationSubnormal temperatureDepressed or abolished reflexesComplete unconsciousness; coma; anesthesiaComa0.35-0.50
Impaired consciousness; sleep or stuporVomiting; incontinence of urine and fecesMarked muscular incoordination; inability to stand or walkMarkedly decreased response to stimuliGeneral inertia; approaching loss of motor functionsStupor0.25-0.40
Apathy, lethargy
Increased muscular incoordination; staggering gait; slurredspeech
Increased pain threshold
Disturbances of vision (diplopia, etc.) and of perception ofcolor, form, motion, dimensions
Exaggerated emotional states (fear, rage, grief, etc.)Disorientation, mental confusion; dizzinessConfusion0.18-0.30
DrowsinessSensory-motor incoordination; impaired balance
Reduced visual acuity, peripheral vision, and glarerecovery
Decreased sensory response; increased reaction timeImpairment of perception, memory, and comprehensionEmotional instability; loss of critical judgmentExcitement0.09-0.25
Loss of efficiency in critical performance testsSlowed information processingBeginning of sensory-motor impairmentDiminution of attention, judgment, and controlIncreased self-confidence; decreased inhibitionsMild euphoria, sociability, talkativenessEuphoria0.03-0.12
Impairment detectable by special testsBehavior nearly normal by ordinary observationInfluence/effects not apparent or obviousSub clinical0.01-0.05
Clinical Signs/Symptoms
Stage ofAlcoholicInfluence
Blood-AlcoholConcentrationg/100mL
Human Performance Toxicology
Human Performance Toxicology
Drugs and driving
DEC program
Drug recognition expert
Toxicologist
Prosecution
Human Performance Toxicology
Human Performance Toxicology
Drug Recognition Evaluation - 12 Step Process Breath alcohol test Interview of the arresting officer. Preliminary examination of the suspect. Examination of the eyes. Divided attention psychophysical tests. Vital signs examination.
Human Performance Toxicology
Human Performance Toxicology
Drug Recognition Evaluation (continued) Dark room examination. Examination of muscle tone. Examination for injection sites. Suspect’s statements and other
observations. Opinion of the evaluator. Toxicological examination.
Human Performance Toxicology
Human Performance Toxicology
Drug Recognition Evaluation
Human Performance Toxicology
Human Performance Toxicology
Drug Recognition Evaluation
Human Performance Toxicology
Human Performance Toxicology
Drug Recognition Evaluation (continued)
Toxicology
Type of Testing
Specimens
Human Performance Toxicology
Human Performance Toxicology
Drug Recognition Evaluation (continued) Drug Class Effects
Central Nervous System DepressantsCentral Nervous System StimulantsHallucinogensPhencyclidineNarcotic Analgesics InhalantsCannabis
Forensic Drug TestingForensic Drug Testing
Introduction History
Military Criminal justice system Public sector Private sector
Rationale
Forensic Drug TestingForensic Drug Testing
Uses in the workplace: Pre-employment screening Post-accident testing Return to Work testing “For Cause” testing Random testing
Forensic Drug Testing Forensic Drug Testing
Military ExperienceMilitary Experience
Forensic Drug Testing Forensic Drug Testing
President Ronald Reagan
1986
Executive Order No. 12564
Objective: To develop a
“drug-free” workplace.
President Ronald Reagan
1986
Executive Order No. 12564
Objective: To develop a
“drug-free” workplace.
Forensic Drug Testing Forensic Drug Testing
Mandatory Guidelines
for Federal
Workplace
Drug Testing
Programs
Mandatory Guidelines
for Federal
Workplace
Drug Testing
Programs
Forensic Drug Testing Forensic Drug Testing
Mandatory Guidelines
Laboratory AccreditationSpecified Menu & Cutoffs
Proficiency TestingInspections
External Blind ControlsCorrective Actions
Mandatory Guidelines
Laboratory AccreditationSpecified Menu & Cutoffs
Proficiency TestingInspections
External Blind ControlsCorrective Actions
Forensic Drug Testing Forensic Drug Testing
Programs:Federal Dept. of Health & Human
Services (DHHS)
National Institute on Drug Abuse (NIDA)
Substance Abuse & Mental Health Services Administration (SAMHSA)
Programs:Federal Dept. of Health & Human
Services (DHHS)
National Institute on Drug Abuse (NIDA)
Substance Abuse & Mental Health Services Administration (SAMHSA)
Forensic Drug Testing Forensic Drug Testing
Programs:Department of Transportation
(DOT)Nuclear Regulatory Commission
(NRC)College of American Pathologists
(CAP)Forensic Urine Drug Testing (FUDT)
Programs:Department of Transportation
(DOT)Nuclear Regulatory Commission
(NRC)College of American Pathologists
(CAP)Forensic Urine Drug Testing (FUDT)
Forensic Drug Testing Forensic Drug Testing Specimen Collection
External Custody & Control Form
Unobserved/Observed Collection
Toilet Water (Off or Blue)
Sink Water (Off or Cold)
No purses or bags
No large coats
Minimum Volume
Check Temperature
Split specimen
Specimen Bottle Seal
Specimen Collection
External Custody & Control Form
Unobserved/Observed Collection
Toilet Water (Off or Blue)
Sink Water (Off or Cold)
No purses or bags
No large coats
Minimum Volume
Check Temperature
Split specimen
Specimen Bottle Seal
Forensic Drug Testing Forensic Drug Testing Standard
Operating
Procedures
SOP
Standard
Operating
Procedures
SOP
Forensic Drug Testing Forensic Drug Testing Test Menus – SAMHSA
Screen for Drugs:
Amphetamines
Cannabinoids
Cocaine Metabolite
Opiates
Phencyclidine
(Alcohol)
Test Menus – SAMHSA
Screen for Drugs:
Amphetamines
Cannabinoids
Cocaine Metabolite
Opiates
Phencyclidine
(Alcohol)
Forensic Drug Testing Forensic Drug Testing
Test Menus – SAMHSADrugs Confirmed:
Amphetamine, MethamphetamineDelta-9-Tetrahydrocannabinol Carboxylic
Acid (THCA)Benzoylecgonine
Codeine, Morphine, 6-AcetylmorphinePhencyclidine
(Alcohol)
Test Menus – SAMHSADrugs Confirmed:
Amphetamine, MethamphetamineDelta-9-Tetrahydrocannabinol Carboxylic
Acid (THCA)Benzoylecgonine
Codeine, Morphine, 6-AcetylmorphinePhencyclidine
(Alcohol)
Forensic Drug Testing Forensic Drug Testing Test Menus – SAMHSA
Specimen Validity:
Temperature
pH
Creatinine
Specific Gravity
Nitrite
Pyridine, Glutaraldehyde, Bleach, Soap, Chromium
Test Menus – SAMHSA
Specimen Validity:
Temperature
pH
Creatinine
Specific Gravity
Nitrite
Pyridine, Glutaraldehyde, Bleach, Soap, Chromium
Forensic Drug Testing Forensic Drug Testing
Test Menus – CAP & non-DOTDrugs:
“NIDA-5”plus
Barbiturates, benzodiazepines,methadone, propoxyphene
MDA, MDMAOthers?
Test Menus – CAP & non-DOTDrugs:
“NIDA-5”plus
Barbiturates, benzodiazepines,methadone, propoxyphene
MDA, MDMAOthers?
Forensic Drug Testing Forensic Drug Testing
Test Menus – CAP
Validity:
Same as SAMHSA
Test Menus – CAP
Validity:
Same as SAMHSA
Forensic Drug Testing Forensic Drug Testing
Test ProceduresSAMHSA / DOT
Screening: Immunoassay (Emit, RIA, FPIA, CEDIA)
Confirmation: GC/MSAlcohol: Alcohol Screening Device
Evidential Breath TesterGC
Test ProceduresSAMHSA / DOT
Screening: Immunoassay (Emit, RIA, FPIA, CEDIA)
Confirmation: GC/MSAlcohol: Alcohol Screening Device
Evidential Breath TesterGC
Forensic Drug Testing Forensic Drug Testing
Test ProceduresCAP & Non-DOT
Screening: Immunoassay (Emit, RIA, FPIA, CEDIA)
Automated Clinical Analyzer (EtOH)Alcohol: Alcohol Screening Device
Confirmation: GC, GC/MSAlcohol: Evidential Breath Tester
GC
Test ProceduresCAP & Non-DOT
Screening: Immunoassay (Emit, RIA, FPIA, CEDIA)
Automated Clinical Analyzer (EtOH)Alcohol: Alcohol Screening Device
Confirmation: GC, GC/MSAlcohol: Evidential Breath Tester
GC
Forensic Drug Testing Forensic Drug Testing
Cutoff Concentration
That concentration below which the analytical result must be reported as
“Negative”
A cutoff concentration is specified for screening analysis and for
confirmation analysis for each analyte.
Cutoff Concentration
That concentration below which the analytical result must be reported as
“Negative”
A cutoff concentration is specified for screening analysis and for
confirmation analysis for each analyte.
Forensic Drug Testing Forensic Drug Testing
Cutoff Concentrations (ng/mL)
Phencyclidine
Screening 25
Confirmation 25
Cutoff Concentrations (ng/mL)
Phencyclidine
Screening 25
Confirmation 25
Forensic Drug TestingForensic Drug Testing
Cutoff Concentrations (ng/mL)
Screening
Cocaine metabolites 300
Confirmation
Benzoylecgonine 150
Cutoff Concentrations (ng/mL)
Screening
Cocaine metabolites 300
Confirmation
Benzoylecgonine 150
Forensic Drug TestingForensic Drug Testing
Cutoff Concentrations (ng/mL)
Screening
Marijuana metabolites 50
Confirmation
Delta-9-THCA 15
Cutoff Concentrations (ng/mL)
Screening
Marijuana metabolites 50
Confirmation
Delta-9-THCA 15
Forensic Drug Testing Forensic Drug Testing
Cutoff Concentrations (ng/mL)
Screening
Amphetamines 1000
Confirmation
Amphetamine 500
Methamphetamine 500
(and Amphetamine 200)
Cutoff Concentrations (ng/mL)
Screening
Amphetamines 1000
Confirmation
Amphetamine 500
Methamphetamine 500
(and Amphetamine 200)
Forensic Drug Testing Forensic Drug Testing
Cutoff Concentrations (ng/mL)
Screening
Opiates 2000
Confirmation
Codeine 2000
Morphine 2000
(Test for 6-AM 10)
Cutoff Concentrations (ng/mL)
Screening
Opiates 2000
Confirmation
Codeine 2000
Morphine 2000
(Test for 6-AM 10)
Forensic Drug Testing Forensic Drug Testing
Security of
Laboratory
Facility
Security of
Laboratory
Facility
Forensic Drug Testing Forensic Drug Testing
Chain of Custody
External Custody and
Control Form
Internal Chain of
Custody Forms
(Specimen and aliquots)
Chain of Custody
External Custody and
Control Form
Internal Chain of
Custody Forms
(Specimen and aliquots)
Forensic Drug Testing Forensic Drug Testing
Specimen Storage
Refrigerated while analyses in process;
Discarded if negative;
Frozen ( -20 o C) > 1 year if
positive.
Specimen Storage
Refrigerated while analyses in process;
Discarded if negative;
Frozen ( -20 o C) > 1 year if
positive.
Forensic Drug TestingForensic Drug Testing
Validation of:
Methods
Instruments
Reagents
Validation of:
Methods
Instruments
Reagents
Forensic Drug Testing Forensic Drug Testing
Reporting Results
“Negative” if either screening or confirmation gives negative result.
“Positive” only if positive result for both screening and confirmation.
“Test Not Performed”
Reporting Results
“Negative” if either screening or confirmation gives negative result.
“Positive” only if positive result for both screening and confirmation.
“Test Not Performed”
Forensic Drug Testing Forensic Drug Testing Reporting Results
Rejected for Testing
(Give Remark)Fatal Flaw
Uncorrected FlawSpecimen UnsuitableSpecimen AdulteratedSpecimen Substituted
Reporting Results
Rejected for Testing
(Give Remark)Fatal Flaw
Uncorrected FlawSpecimen UnsuitableSpecimen AdulteratedSpecimen Substituted
Forensic Drug Testing Forensic Drug Testing Reporting Results
If specimen donor requests, “split” specimen may be sent to another
certified laboratory to retest for that substance reported positive.
Reporting Results
If specimen donor requests, “split” specimen may be sent to another
certified laboratory to retest for that substance reported positive.
Forensic Drug Testing Forensic Drug Testing
Quality Control /
Quality Assurance
Screening Quality Control
Confirmation Quality Control
Proficiency Testing
Quality Control /
Quality Assurance
Screening Quality Control
Confirmation Quality Control
Proficiency Testing
Forensic Drug Testing Forensic Drug Testing
Screening Quality Control
Calibrator / Cutoff
Controls:
Open - Blank, Negative, Positive,
Blinds (external and internal)
Screening Quality Control
Calibrator / Cutoff
Controls:
Open - Blank, Negative, Positive,
Blinds (external and internal)
Forensic Drug Testing Forensic Drug Testing
Confirmation Quality Control
Calibrators:
Single vs. Multiple point
Controls:
Open - Blank, Negative, Positive,
Blinds (external and internal)
Carryover
Confirmation Quality Control
Calibrators:
Single vs. Multiple point
Controls:
Open - Blank, Negative, Positive,
Blinds (external and internal)
Carryover
Forensic Drug Testing Forensic Drug Testing
Proficiency Tests
Samples submitted by an outside agency.
May be negative;
May be positive.
Proficiency Tests
Samples submitted by an outside agency.
May be negative;
May be positive.
Forensic Drug Testing Forensic Drug Testing
Proficiency Tests
No false positives
Identify 90% of drug challenges
Quaititate 80% within +/- 20% or +/- 2 SD of target value.
Proficiency Tests
No false positives
Identify 90% of drug challenges
Quaititate 80% within +/- 20% or +/- 2 SD of target value.
Forensic Drug Testing Forensic Drug Testing Inspections
Semi-AnnualNumber of Inspectors &
Number of DaysDepends on size of laboratory
Review SOP, talk to staff, watch sample processing, look at lots of case records,
personnel records, proficiency test records, security records, instrument logs, etc., etc., etc.
InspectionsSemi-Annual
Number of Inspectors &Number of Days
Depends on size of laboratoryReview SOP, talk to staff, watch sample processing, look at lots of case records,
personnel records, proficiency test records, security records, instrument logs, etc., etc., etc.
Forensic Drug Testing Forensic Drug Testing Personnel
New Titles:
Responsible Person (RP)
Certifying Scientist
Medical Review Officer (MRO)
Collector
Accessioner
Records Custodian
Personnel
New Titles:
Responsible Person (RP)
Certifying Scientist
Medical Review Officer (MRO)
Collector
Accessioner
Records Custodian
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