Forensic Toxicology

Forensic toxicology

is the use of toxicology and other disciplines such as analytical chemistry, pharmacology,clinical chemistry to aid medico legal investigation of death, poisoning, and drug use.

Alphonse Bertillon was a French criminologist and anthropologist who created the first system of physical measurements, photography, and record keeping that police could use to identify criminals.

History of Forensic science

In 44BC following the assassination of Julius Caesar the attending physician proclaimed that of the 23 wounds found on the body ‘only one’ was fatal.

In 1247 the first textbook on forensic medicine is published in China which among others things documents the procedures to be followed when investigating a suspicious death.

Sir Edward Richard Henry developed the print classification system that would come to be used in Europe and North America. He published Classification and Uses of Finger Prints.

Samples

Urine Blood Hair Saliva Gastric contents Vitreous humor Liver Brain Lung

Forensic DNA

Mitochondrial DNA (mtDNA) Valuable tool for determining the source

of DNA recovered from damaged, degraded and small biological samples.

Mitochondrial DNA (mtDNA) is inherited maternally.

Evidence Left Behind at A Crime Scene

Biological material e.g. blood, semen or saliva Fibers Paint Chips Glass Soil & Vegetation Accelerants Fingerprints Hair Impression evidence e.g. shoe prints, tire tracks or tool

marks Fracture patterns . Glass fragments or Adhesive tape pieces Narcotics

Toxicology Principles in the Management of Acute Poisoning

Clinical Toxicology

Clinical toxicology focuses on effects of overdose of substances in patients by

Accidental poisoning Intentional overdosing of medications Drugs of abuse Household chemicals Or various industrial chemicals of non clinical

nature

Statistical Data on Poisoning Epidemiology in United States Approx 3.5 million people were poisoned in 2006 In 2007, 29,846 (74 percent) of the 40,059 poisoning deaths in

the United States were unintentional In 2007, 93 percent of unintentional poisoning deaths were

caused by drugs. Opioid pain medications, such as methadone, hydrocodone, or oxycodone, were most commonly involved, followed by cocaine and heroin

In 2009, unintentional poisoning caused about 708,318 Emergency Department (ED) visits

In 2009, poisonings led to $93.4 billion in medical and productivity costs

Principles of Management

Among important toxicological principles that are applied in evaluating the poisoned individual are

Exposure and aspects related to reducing absorptionDose response considerationsTarget tissue and systemic effectsChemical interactionsChemical antagonism as a management approachAcute versus Chronic effects

General Management

1) Supportive Care (to sustain the vital signs) A Airway Clearance B Breathing maintenance C Circulation enhancement D Decontamination

2) Treat the patients depressed mental status

3) Rule out or treat hypoglycemia

4) Obtain history of the exposure

What substance was exposed How much was consumed or exposed Route of ingestion or exposure Time since exposure

5) Identify Signs and symptoms of poisoning Breathing rate, heart rate, dilation of pupil, Fits,

injuries or diseases associated to the symptoms

6) Neurologic Examination Slurred speech, imbalancement, tremors

unconsciousness, seizures, confusion, headache