Forensic Toxicology

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Forensic Toxicology
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Definition

• Using the study of adverse effects of chemicals
  on living organisms to aid in the investigation
  of death and poisoning
• Forensic toxicology is a specialty area of
  analytical chemistry

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Toxins

• A material that exerts a life threatening effect
  on an organism
• They may be ingested, inhaled, or absorbed
  through the skin
• Poisons are subgroup of toxins

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US Poisonings

• About 2 million voluntarily reported poisonings
  per year
• About 700 deaths by poisoning per year
• Children under 6 account for the majority and are
  accidental poisonings
• Adult poisonings are mostly intentional

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Most frequent deaths by poisoning

• 1-Antidepressant medications
• 2-Analgesics
• 3-Street drugs
• 4-Cardiovascular drugs
• 5-Alcohol
• 6-Gases and fumes
• 7-Asthma therapies
• 8-Industrial chemicals
• 9-Pesticides
• 10-Household cleaning supplies
• 11-Anticonvulsant medications
• 12-Food, plants, and insects

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Examples of evidence collected at crime scene

• Pill bottles
• Powders
• Trace residues
• Any available chemicals
• These, of course, would make the case simpler if
  found at the scene, but are not always available

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Useful evidence involving the victims body

• Hair
• Blood
• Organ parts
• Gastric (stomach) contents

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The challenge

• The bodys natural processes alter, or change the
  composition of substances ingested
• The forensic toxicologist should have the
  coroners report available, which might contain
  previous signs and symptoms of deceased as well
  as important post mortem data

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Detecting and classifying

• Gas chromatography- examines organic compounds
• Emission Spectroscopy, X-ray diffraction and the
  Reinsch test-used to detect heavy metals
• Thin-layer chromatography, gas-liquid
  chromatography, and immunoassay- used to detect
  both legal and illegal drugs, pollutants, and
  pesticides

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Drugs

• Drugs are usually acidic or basic in nature
• When a toxicologist isolates a drug sample, the
  sample will be first tested to see if it
  possesses an acidic or basic nature
• Then, physical tests such as melting point
  determination, boiling point determination or
  density determination
• Chromatography and chemical spot tests are also
  used in the screening process
• Finally, the use of mass spectroscopy will
  confirm the identity of the drug

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Forensic Toxicologists

• Undergraduate degree in biology or chemistry
• PhD in one of the natural sciences

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Sources

• http//faculty.ncwc.edu/toconnor/425/425lect14.htm
  
• http//en.wikipedia.org/wiki/Forensic_toxicology