Clinical Toxicology and Biological Investigation

• What are the external signs of drug influence

  Pulse rate, dilated pupils, behaviour and vitals
• Acute toxicity


  Vomitting

  cramps

  Headache
• Signs of chronic toxicity

  liver damage

  Nephrotoxicity
• Techniques for analysis


  TICTAC database

  FTIRE

  TLC
• What is immunoassay used for?


  Urine, saliva, blood and hair
• What are screening tests?


  Semi quantitative, fast, low cost and low specific test
• What are confirmatory tests?

  High cost, slow, quantitative, sensitive and specific tests
• Role of a Forensic Toxicologist


  Analyse bodily fluids and samples

  determine the cause of death with the coroner and pathologist
• Coroner role


  Independent judicial officer responsible for medico legal investigation of reported deaths

  request post mortem
• Pathologist


  Medically trained professional who performs autospies

  Approved by the Home Office to perform forensic autopsies
• Samples taken at autopsy


  Heart blood

  Peripheral Blood

  Vitreous Humour

  Bile

  Urine

  Stomach contents
• What is needed for a post mortem?


  Case history such as age, sex, weight, history, medication, occupation

  Samples

  Tox analysis

  Expert witness interpretations
• Bulk samples


  A seized amount that is large enough to weigh
• Trace Samples


  A seized sample that is not large enough to weigh
• What precautions need to be taken in the lab?

  Clean equipment, use pure chemicals, use standards

  Contaminants give false positives and cross react with poisons
• Presumptive Tests


  Determine the class of drug

  FPN colour tests for phenothiazines (ferric, perchloric and nitric acid)

  Immunoassay for opiates, amfetamines and benzodiazepines
• Confirmatory Tests


  GCMS

  HPLC

  Qualitative and quantitative

  matrix match required
• The ceoncentration if drugs needs to be related to known affects because …


  it can determine the cause of death, was it a contributory factor, identify route, dose and time of administratiin
• High levels in the GI and liver such

  Ingestion
• High levels in the lungs and blood suggest …

  Inhalation Or intravenous injection
• Hair


  Shows chronic exposure

  1cm to 1 month detection of deygs

  hair can be collected at any time and has less contamination than samples like urine

  0.5g-1g

  used to identity drugs like cocaine, ecstasy, barbituates, alcohol. Benzodiazepines and amfetatmines