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Postmortem Toxicology

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Postmortem Toxicology Powered By Docstoc
					  Forensic
 Toxicology



Father of Modern Toxicology
Forensic
Toxicology
"All things are poison
and nothing is without
poison, only the dose
permits something not
to be poisonous.”
-Paracelsus
(1530 AD)
 Forensic Toxicology

"All things are poison and nothing is
without poison, only the dose permits
   something not to be poisonous.”
             -Paracelsus
                 Toxicology
• What is it??
  – Analysis of biological fluids for the presence of
    controlled substances, common pharmaceuticals
    and poisons.

• What do Toxicologists know?
  – All about drug interactions, metabolism,
    therapeutic vs. toxic doses, and impairment
                 Toxicology
Antemortem = before death   Postmortem = after death

                            • Homicides
• DUIs
                            • Suicides
• Drug Facilitated Sexual   • Overdose (intentional v.s.
  Assault                     accidental)
• Workplace Drug Testing    • MVA (motor vehicle
• Parole violations           accident)
                            • Unexplained death
                            • Natural (sometimes)
              Types of Samples

•   Blood
•   Urine
•   Vitreous humor
•   Gastric contents
•   Tissue: Liver, Spleen, Brain
•   Maggots
Summary of Drug Categories
• CNS depressants

• CNS stimulants

• Narcotic Analgesics

• Cannabis

• Hallucinogens

• Dissociative Anesthetics
     Combinations of Drugs
What is the most common combination of
 drugs in postmortem tox cases?


What is the most common combination of
 drugs in antemortem DUII cases?


What is the most common drug identified
 in Drug-Facilitated Sexual Assault
 cases?
        Sample prep:
Solid Phase Extraction (SPE)




                   Sample
                   collection tubes
     Gas chromatograph/Mass spectrometer

              1. Autosampler



                                2. Injection port




                               3. Oven/column
5. Data
analysis




           4. Mass spec
                Case 1:
   Challenge from beyond the grave

• 24 year old male; suspected suicide

• Note:
  “CSI: Save your time and money.
   I did not use drugs or alcohol.”
                     Case 1:
        Challenge from beyond the grave
• Results (Blood):

        Ethanol             0.00 g/dL

        Nortriptyline       0.889 mg/L
        Methamphetamine     0.189 mg/L

        Amphetamine         0.113 mg/L

        Hydrocodone          0.030 mg/L
        Carboxyhemoglobin   1.7 %

Results (Gastric):
         Nortriptyline
             Case 2:
Decomposed = limited sample options

• 47 year old male
• Recovered from Willamette river
• Significantly decomposed
• Liver & spleen submitted for
  analysis
               QuickTime™ and a
                 decompressor
        are needed to see this picture.
Liver
                QuickTime™ and a
                  decompressor
         are needed to see this picture.




Spleen
Homogenization of liver
             Case 2:
Decomposed = limited sample options


Results (Liver):

   Methamphetamine:   1.58 ug/g
      Cannabinoids:   Indicated
               Case 3:
      Highest Postmortem BAC

• Female, 42
• Chronic alcoholic
• Drank vodka, went to sleep
• Found by family several hours later
• Rx for lithium, lorazepam,
  diazepam
                 Case 3:
        Highest Postmortem BAC
Results (Blood):



        Ethanol:        0.63 g/dL

      Lorazepam:       0.050 mg/L
        Case 4: Fentanyl

• Female, 56

• Found in hot tub wearing
  multiple fentanyl patches
                Case 4: Fentanyl

Results (Blood):



          Fentanyl :                  49 ng/mL

Blood Fentanyl concentrations in fatal cases:
              3.0 – 28 ng/mL

           Disposition of Toxic Drugs and Chemicals in Man, 5th ed.
Fentanyl
   Case 5: Choking or OD?

• Male dies; friends allege he choked
  on steak

• Overdose was suspected
     Case 5: Choking or OD?
• Results (Blood):


    Methamphetamine:            1.22 mg/L
       Amphetamine:            0.099 mg/L


• Blood Methamphetamine average in fatal
  cases:
                 0.96 mg/L
                                (Logan et al, 1998)
Fire, auto exhaust, & hibachi
     Fire, auto exhaust, & hibachi

•Fire deaths
  •Was the individual deceased prior
  to the fire?
•Found in vehicle
  •Suicide by auto exhaust?
•Found in small room (bathroom) with
charcoal grill or hibachi
  •Suicide by CO inhalation?
Carboxyhemoblobin (COHb)
% COHb

  1 – 5%    Environmental, Smoker




 15 – 35%           Toxic




  > 50%            Lethal
          Case 6:
    Non-compliant diabetic
• Vitreous electrolytes and glucose

• Typical vitreous glucose:
               0 – 150 mg/dL

• Glucose > 1000 mg/dL
      Case 6:
Non-compliant diabetic
                 Blood Ethanol Analysis
                 •Ethanol (quantitated)
                 •Methanol
                 •Isopropanol
                 •Acetone
                 •Acetaldehyde




        GC-FID
Pills in gastric contents

				
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posted:8/1/2011
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