Presentation on theme: "TOXICOLOGY OF ALCOHOL. 2 Toxicology Toxicology—the study of the adverse effects of chemicals or physical agents on living organisms Types: Environmental—air,"— Presentation transcript:
2 Toxicology Toxicology—the study of the adverse effects of chemicals or physical agents on living organisms Types: Environmental—air, water, soil Consumer—foods, cosmetics, drugs Medical, clinical, forensic
3 Forensic Toxicology Postmortem—medical examiner or coroner Criminal—motor vehicle accidents (MVA) Workplace—drug testing Sports—human and animal Environment—industrial, catastrophic, terrorism
4 Toxicology Toxic substances may: Be a cause of death Contribute to death Cause impairment Explain behavior
5 Aspects of Toxicity Dosage The chemical or physical form of the substance The mode of entry into the body Body weight and physiological conditions of the victim, including age and sex The time period of exposure The presence of other chemicals in the body or in the dose
6 Lethal Dose LD 50 refers to the dose of a substance that kills half the test population, usually within four hours Expressed in milligrams of substance per kilogram of body weight
7 Toxicity Classification LD 50 (rat,oral)Correlation to Ingestion by 150-lb Adult Human Toxicity <1 mg/kga taste to a dropextreme 1–50 mg/kgto a teaspoonhigh 50–500 mg/kgto an ouncemoderate 500–5,000 mg/kgto a pintslight 5–15 g/kgto a quartpractically nontoxic Over 15 g/kgmore than 1 quartrelatively harmless
8 Symptoms of Various Types of Poisoning Symptom/Evidence Characteristic burns around the lips and mouth of victim Red or pink patches on the chest and thigh, unusually bright red lividity Black vomit Greenish-brown vomit Yellow vomit Coffee-brown vomit, onion or garlic odor Burnt almond odor Extreme diarrhea Nausea and vomiting, unconsciousness possibly blindness Type of Poison Caustic poison (lye) Carbon monoxide Sulfuric acid Hydrochloric acid Nitric acid Phosphorus Cyanide Arsenic, mercury Methyl (wood) or isopropyl (rubbing) alcohol
9 To Prove a Case Prove a crime was committed Motive Intent Access to poison Access to victim Death was homicidal Death was caused by poison
10 Alcohol—Ethyl Alcohol (C 2 H 5 OH) Most abused drug in America About 40 percent of all traffic deaths are alcohol-related Toxic—affecting the central nervous system, especially the brain Colorless liquid, generally diluted in water Acts as a depressant Alcohol appears in blood within minutes of consumption; 30–90 minutes for full absorption Detoxification—about 90 percent in the liver About 5 percent is excreted unchanged in breath, perspiration, and urine
Introduction A major branch of forensic toxicology deals with the measurement of alcohol in the body for matters that pertain to violations of criminal law.
12 Rate of Absorption Depends on: Amount of alcohol consumed The alcohol content of the beverage Time taken to consume it Quantity and type of food present in the stomach Physiology of the consumer
Toxicology of Alcohol The analysis of alcohol exemplifies the primary objective of forensic toxicology—the detection and isolation of drugs in the body for the purpose of determining their influence on human behavior. Alcohol, or ethyl alcohol, is a colorless liquid normally diluted with water and consumed as a beverage.
Toxicology of Alcohol Like any depressant, alcohol principally effects the central nervous system, particularly the brain.
Alcohol Levels Factors such as time taken to consume the drink, the alcohol content, the amount consumed, and food present in the stomach determine the rate at which alcohol is absorbed.
Alcohol Levels Elimination of alcohol throughout the body is accomplished through oxidation and excretion. Oxidation takes place almost entirely in the liver, while alcohol is excreted unchanged in the breath, urine, and perspiration. The extent to which an individual may be under the influence of alcohol is usually determined by either measuring the quantity of alcohol present in the blood system or by measuring the alcohol content in the breath.
Alcohol & Circulatory System Humans have a closed circulatory system consisting of a heart, arteries, veins, and capillaries.
Alcohol & Circulatory System Alcohol is absorbed from the stomach and small intestines into the blood stream. Alcohol is carried to the liver where the process of its destruction starts.
Alcohol & Circulatory System Blood, carrying alcohol, moves to the heart and is pumped to the lungs.
Alcohol & Circulatory System In the lungs, carbon dioxide and alcohol leave the blood and oxygen enters the blood in the air sacs known as alveoli. Then the carbon dioxide and alcohol are exhaled during breathing.