Toxicology Poisons and Alcohol If all those buried

Toxicology: Poisons and Alcohol “If all those buried in our cemeteries who were poisoned could raise their hands, we would probably be shocked by the numbers. ” —John Harris Trestrail, “Criminal Poisoning” Chapter 8

Toxicology Definition—the study of the adverse effects of chemicals or physical agents on living organisms. Types: NEnvironmental — air, water, soil NConsumer — foods, cosmetics, drugs NMedical, clinical, forensic Chapter 8 Kendall/Hunt Publishing Company 1

Forensic Toxicology N Postmortem — medical examiner or coroner N Criminal — motor vehicle accidents (MVA) N Workplace—drug testing N Sports—human and animal N Environment—industrial, catastrophic, terrorism Chapter 8 Kendall/Hunt Publishing Company 2

Toxicology Toxic substances may: N Be a cause of death N Contribute to death N Cause impairment N Explain behavior Chapter 8 Kendall/Hunt Publishing Company 3

Historical Perspective of Poisoners N N Olympias — a famous Greek poisoner Locusta — personal poisoner of Emperor Nero Lucretia Borgia — her father was Pope Alexander VI Madame Giulia Toffana — committed over 600 successful poisonings, including two Popes. N Hieronyma Spara—formed a society to teach women how to murder their husbands N Madame de Brinvilliers and Catherine Deshayes— French poisoners. AND many others through modern times. Chapter 8 Kendall/Hunt Publishing Company 4

People of Historical Significance Mathieu Orfila — known as the father of forensic toxicology, published in 1814 “Traite des Poisons” which described the first systematic approach to the study of the chemistry and physiological nature of poisons. Chapter 8 Kendall/Hunt Publishing Company 5

Aspects of Toxicity N Dosage N The chemical or physical form of the substance N The mode of entry into the body N Body weight and physiological conditions of the victim, including age and sex N The time period of exposure N The presence of other chemicals in the body or in the dose Chapter 8 Kendall/Hunt Publishing Company 6

Aspects of Toxicity The time period of exposure N Chronic exposure • Larger amounts spread out over a long period of time • Causes medical problems such as weakness, sluggishness, hair & weight loss, mental instability, and skin & liver cancer. N Acute exposure • Refers to a dose large enough to cause immediate problems, including death. Chapter 8 Kendall/Hunt Publishing Company 7

Aspects of Toxicity The presence of other chemicals in the body or in the dose of the toxin: N Synergism • the combination of two chemicals increases their individual effects • ex: sedatives and alcohol N Antagonism • the combination of two chemicals decreases their individual effects • ex: some blood-pressure medicines and OTC cold medicines with decongestants Chapter 8 Kendall/Hunt Publishing Company 8

Lethal Dose N LD 50—refers to the dose of a substance that kills half the test population (lab rats), usually within four hours. N Expressed in milligrams of substance per kilogram of body weight Chapter 8 Kendall/Hunt Publishing Company 9

Toxicity Classes LD 50 (rat, oral) Correlation to Ingestion by 150 lb Adult Human Toxicity <1 mg/kg a taste to a drop extremely 1 -50 mg/kg to a teaspoon highly 50 -500 mg/kg to an ounce moderately 500 -5000 mg/kg to a pint slightly 5 -15 g/kg to a quart practically non-toxic Over 15 g/kg more than 1 quart relatively harmless Chapter 8 Kendall/Hunt Publishing Company 10

Some Lethal Doses Material LD 50, mg/kg, rats, oral Sucrose (sugar) 29, 700 Ethanol (ethyl alcohol) 7, 060 Sodium chloride (table salt) 3, 000 Caffeine 192 Sodium cyanide (spy novels – poison capsules) 6. 4 Ricin 0. 020 Botulin toxin 0. 000005 – 0. 00005 Chapter 8 Kendall/Hunt Publishing Company 11

It’s All in the Dose? N “All substances are poisons. There is none which is not. The right dose differentiates a poison and remedy. ” N —Paracelsus (1495 -1541). Swiss physician and chemist Chapter 8 N Hormesis refers to the concept that substances that kill at high dosages are actually beneficial at low dosages. N Ex: botulin used to erase wrinkles and ease migraines. Kendall/Hunt Publishing Company 12

Federal Regulatory Agencies N Food and Drug Administration (FDA) – deals with pharmaceuticals, food additives, and medical devices. N Environmental Protection Agency (EPA) – works with agricultural and industrial chemicals released to the environment. Chapter 8 Kendall/Hunt Publishing Company 13

Federal Regulatory Agencies N Consumer Product Safety Commission – concerned with toxins in consumer products. N Department of Transportation (DOT) – watches over the shipment of toxic chemcials N Occupational Safety and Health Administration (OSHA) – is concerned with exposure to chemicals in the workplace. Chapter 8 Kendall/Hunt Publishing Company 14

Symptoms of Various Types of Poisoning Type of Poison Symptom/Evidence N Caustic Poison (lye) Characteristic burns around the lips and mouth of the victim N Carbon Monoxide Red or pink patches on the chest and thighs, unusually bright red lividity Chapter 8 Kendall/Hunt Publishing Company 15

Symptoms of Various Types of Poisoning Type of Poison Symptom/Evidence N Sulfuric acid N Hydrochloric acid N Nitric acid N Phosphorous Black vomit Greenish-brown vomit Yellow vomit Coffee-brown vomit; onion or garlic odor Chapter 8 Kendall/Hunt Publishing Company 16

Symptoms of Various Types of Poisoning Type of Poison Symptom/Evidence N Cyanide N Arsenic, Mercury N Methyl alcohol Burnt almond odor Pronounced diarrhea Nausea & vomiting, unconsciousness aka wood alcohol N Isopropyl alcohol Possibly blindness aka rubbing alcohol Chapter 8 Kendall/Hunt Publishing Company 17

Critical Information on Poisons —John Trestrail from “Criminal Poisoning” N Form N Common color N Characteristic odor N Solubility N Taste N Common sources N Lethal dose N Mechanism N Possible methods of administration N Time interval of onset of symptoms. Chapter 8 Kendall/Hunt Publishing Company 18

Critical Information on Poisons —John Trestrail from “Criminal Poisoning” N Symptoms resulting from an acute exposure N Symptoms resulting from chronic exposure N Disease states mimicked by poisoning N Notes relating to the victim N Specimens from victim N Analytical detection methods N Known toxic levels N Notes pertinent to analysis of poison N List of cases in which poison was used Chapter 8 Kendall/Hunt Publishing Company 19

To Prove a Case N N N N Prove a crime was committed Motive Intent Access to poison Access to victim Death was caused by poison Death was homicidal Chapter 8 Kendall/Hunt Publishing Company 20

Forensic Autopsy Look for: N Irritated tissues N Characteristic odors N Mees lines—single transverse white bands on nails. Order toxicological screens N Postmortem concentrations should be done at the scene for comparison N No realistic calculation of dose can be made from a single measurement Chapter 8 Kendall/Hunt Publishing Company 21

Human Specimens for Analysis N Blood N Urine N Vitreous Humor of Eyes N Liver tissue N Brain tissue N Kidney tissue N Hair/nails N Bile N Gastric contents Chapter 8 Kendall/Hunt Publishing Company 22