Chapter 8 Toxicology: Poisons and Alcohol “All substances are poisons. There is none which is not. The right dose differentiates a poison and remedy.” —Paracelsus (1495-1541). Swiss physician and chemist

Toxicology Definition—the study of the adverse effects of chemicals or physical agents on living organisms.

Types: Environmental—air, water, soil Consumer—foods, cosmetics, drugs Toxicology Types: Environmental—air, water, soil Consumer—foods, cosmetics, drugs Medical, clinical, forensic

Postmortem—medical examiner or coroner Forensic Toxicology Postmortem—medical examiner or coroner Criminal—motor vehicle accidents (MVA) Workplace—drug testing

Sports—human and animal Forensic Toxicology Sports—human and animal Environment—industrial, catastrophic, terrorism

Toxicology Toxic substances may: Contribute to death Be a cause of death Cause impairment Explain behavior

The Severity of the Problem “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”

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 Aspects of Toxicity The time period of exposure The presence of other chemicals in the body or in the dose

Expressed in milligrams of substance per kilogram of body weight Lethal Dose LD50—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

Toxicity Classes LD50 (rat,oral) Toxicity Correlation to Ingestion by 150 lb Adult Human Toxicity <1mg/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 15g/kg more than 1 quart relatively harmless

Federal Regulatory Agencies Food and Drug Administration (FDA) Environmental Protection Agency (EPA) Consumer Product Safety Commission Department of Transportation (DOT) Occupational Safety and Health Administration (OSHA)

Symptoms of Various Types of Poisoning Type of Poison Symptom/Evidence Caustic Poison (lye) Characteristic burns around the lips and mouth of the victim Carbon Monoxide Red or pink patches on the chest and thighs, unusually bright red lividity Sulfuric acid Black vomit Hydrochloric acid Greenish-brown vomit Nitric acid Yellow vomit

Symptoms of Various Types of Poisoning Type of Poison Symptom/Evidence Phosphorous Coffee brown vomit. Onion or garlic odor Cyanide Burnt almond odor Arsenic, Mercury Pronounced diarrhea Methyl (wood) or Nausea and vomiting, Isopropyl (rubbing) unconsciousness, alcohol possibly blindness

Critical Information on Poisons Common color Characteristic odor Solubility Taste Common sources —John Trestrail from “Criminal Poisoning”

Critical Information on Poisons Mechanism Possible methods of administration Time interval of onset of symptoms. Symptoms resulting from an acute exposure Symptoms resulting from chronic exposure —John Trestrail from “Criminal Poisoning”

Critical Information on Poisons Disease states mimicked by poisoning Notes relating to the victim Specimens from victim Analytical detection methods —John Trestrail from “Criminal Poisoning”

Critical Information on Poisons Known toxic levels Notes pertinent to analysis of poison List of cases in which poison was used —John Trestrail from “Criminal Poisoning”

Prove a crime was committed Motive Intent Access to poison To Prove a Case Prove a crime was committed Motive Intent Access to poison

Death was caused by poison Death was homicidal To Prove a Case Access to victim Death was caused by poison Death was homicidal

Mees lines—single transverse white bands on nails. Forensic Autopsy Look for: Irritated tissues Characteristic odors Mees lines—single transverse white bands on nails.

Order toxicological screens Forensic Autopsy Order toxicological screens Postmortem concentrations should be done at the scene for comparison No realistic calculation of dose can be made from a single measurement

Human Specimens for Analysis Blood Urine Vitreous Humor of Eyes Bile Gastric contents Liver tissue Brain tissue Kidney tissue Hair/nails

Alcohol—Ethyl Alcohol (C2H5OH) Most abused drug in America About 40% of all traffic deaths are alcohol-related Toxic—affecting the central nervous system, especially the brain

Alcohol—Ethyl Alcohol (C2H5OH) Colorless liquid, generally diluted in water Acts as a depressant Alcohol appears in blood within minutes of consumption; 30-90 minutes for full absorption

Alcohol—Ethyl Alcohol (C2H5OH) Detoxification—about 90% in the liver About 5% is excreted unchanged in breath, perspiration and urine

amount of alcohol consumed the alcohol content of the beverage 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

BAC Blood Alcohol Content Expressed as percent weight per volume of blood Legal limits in all states is 0.08% Parameters influencing BAC: Body weight Alcoholic content Number of beverages consumed Time between consumption

BAC Burn off rate of 0.015% per hour but can vary: Male BAC male = 0.071 x (oz) x (% alcohol) body weight Female BAC female = 0.085 x (oz) x (% alcohol)

Henry’s Law When a volatile chemical is dissolved in a liquid and is brought to equilibrium with air, there is a fixed ratio between the concentration of the volatile compound in the air and its concentration in the liquid; this ratio is constant for a given temperature. THEREFORE, the concentration of alcohol in breath is proportional to that in the blood.

Henry’s Law This ratio of alcohol in the blood to alcohol in the alveolar air is approximately 2100 to 1. In other words 1 ml of blood will contain nearly the same amount of alcohol as 2100 ml of breath.

Field Tests Preliminary tests—used to determine the degree of suspect’s physical impairment and whether or not another test is justified.

Psychophysical test— 3Basic Tests Field Tests Psychophysical test— 3Basic Tests Horizontal gaze nystagmus (HGN): follow a pen or small flashlight, tracking left to right with one’s eyes. In general, wavering at 45 degrees indicates 0.10 BAC.

Field Tests Nine Step walk and turn (WAT): comprehend and execute two or more simple instructions at one time. One-leg stand (OLS): maintain balance, comprehend and execute two or more simple instructions at one time.

More practical in the field The Breathalyzer More practical in the field Collects and measures alcohol content of alveolar breath Breath sample mixes with 3 ml of 0.025 % K2Cr2O7 in sulfuric acid and water 2K2Cr2O7 + 3C 2H5OH + 8H 2SO4  2Cr2(SO4)3 + 2K2SO4 + 3CH3COOH + 11 H2O

The Breathalyzer Potassium dichromate is yellow, as concentration decreases its light absorption diminishes so the breathalyzer indirectly measures alcohol concentration by measuring light absorption of potassium dichromate before and after the reaction with alcohol

Breath tests reflect alcohol concentration in the pulmonary artery. Generalizations During absorption, the concentration of alcohol in arterial blood will be higher than in venous blood. Breath tests reflect alcohol concentration in the pulmonary artery.

Generalizations The breathalyzer also can react with acetone (as found with diabetics), acetaldehyde, methanol, isopropyl alcohol, and paraldehyde, but these are toxic and their presence means the person is in serious medical condition.

Generalizations Breathalyzers now use an infrared light absorption device with a digital read-out. Prints out a card for a permanent record.

People in the News John Trestrail is a practicing toxicologist who has consulted on many criminal poisoning cases. He is the founder of the Center for the Study of Criminal Poisoning in Grand Rapids, Michigan which has established an international database to receive and analyze reports of homicidal poisonings from around the world. He is also the director of DeVos Children’s Hospital Regional Poison Center. In addition, he wrote the book, Criminal Poisoning, used as a reference by law enforcement, forensic scientists and lawyers.

Read more about Forensic Toxicology from Court TV’s Crime Library at: More Information Read more about Forensic Toxicology from Court TV’s Crime Library at: http://www.crimelibrary.com/criminal_mind/forensics/toxicology/2.html

Toxicology and Drugs Chapter 7 Drugs “Having sniffed the dead man’s lips, I detected a slightly sour smell, and I came to the conclusion that he had poison forced upon him.” —Sherlock Holmes, in Sir Arthur Conan Doyle’s A Study in Scarlet

Drugs and Crime A drug is a natural or synthetic substance designed to affect the subject psychologically or physiologically.

Drugs and Crime “Controlled substances” are drugs that are restricted by law Controlled Substances Act is a law that was enacted in 1970; it lists illegal drugs, their category and their penalty for possession, sale or use.

Controlled Substances Act Schedule I – high potential for abuse; no currently acceptable medical use in the U.S.; a lack of accepted safety for use under medical supervision

Controlled Substances Act Schedule II – high potential for abuse; a currently accepted medical use with severe restrictions; abuse may lead to severe psychological or physical dependence

Controlled Substances Act Schedule III – lower potential for abuse than the drugs in I or II; a currently accepted medical use in treatment in the U.S.; abuse may lead to moderate physical dependence or high psychological dependence

Controlled Substances Act Schedule IV – low potential for abuse relative to drugs in III; a currently accepted medical use in treatment in the U.S.; abuse may lead to limited physical dependence or psychological dependence relative to drugs in III

Controlled Substances Act Schedule V – low potential for abuse relative to drugs in IV; currently accepted medical use in treatment in the U.S.; abuse may lead to limited physical dependence or psychological dependence relative to drugs in IV

Examples of Controlled Substances and Their Schedule Placement Schedule I—heroin (diacetylmorphine), LSD, marijuana, ecstasy (MDMA) Schedule II—cocaine, morphine, amphetamines (including methamphetamines), PCP, Ritalin

Examples of Controlled Substances and Their Schedule Placement Schedule III—intermediate acting barbiturates, anabolic steroids, ketamine Schedule IV—other stimulants and depressants including Valium, Xanan, Librium, phenobarbital, Darvon

Examples of Controlled Substances and Their Schedule Placement Schedule V—codeine found in low doses in cough medicines

Identification of Drugs PDR—Physicians’ Desk Reference Field Tests—presumptive tests Laboratory Tests—conclusive tests

Human Components Used for Drug Analysis Blood Urine Hair Gastric Contents Bile Liver tissue Brain tissue Kidney tissue Spleen tissue Vitreous Humor of the Eye

Physicians’ Desk Reference PDR—a physicians’ desk reference is used to identify manufactured pills, tablets and capsules. It is updated each year. This can sometimes be a quick and easy identifier of the legally made drugs that may be found at a scene. The reference book gives a picture of the drug, whether it is a prescription, over the counter, or a controlled substance; as well as more detailed information about the drug.

PDR Key

Microcrystalline test— Drug Identification Screening or presumptive tests Spot or color tests Microcrystalline test— a reagent is added that produces a crystalline precipitate which is unique for a certain drug. Chromatography

Confirmatory tests Spectrophotometry Ultraviolet (UV) Visible Drug Identification Confirmatory tests Spectrophotometry Ultraviolet (UV) Visible Infrared (IR) Mass spectrometry

Presumptive Color Tests Marquis—turns purple in the presence of most opium derivatives and orange-brown with amphetamines

Presumptive Color Tests Dillie-Koppanyi—turns violet-blue in the presence of barbiturates Duquenois-Levine—turns a purple color in the presence of marijuana

Presumptive Color Tests Van Urk—turns a blue-purple in the presence of LSD Scott test—color test for cocaine, blue

A technique for separating mixtures into their components Chromatography A technique for separating mixtures into their components Includes two phases—a mobile one that flows past a stationary one. The mixture interacts with the stationary phase and separates.

Types of Chromatography Paper Thin Layer (TLC) Gas (GC) Pyrolysis Gas (PGC) Liquid (LC) High Pressure Liquid (HPLC) Column

Stationary phase—paper Mobile phase—a liquid solvent Paper Chromatography Stationary phase—paper Mobile phase—a liquid solvent Capillary action moves the mobile phase through the stationary phase

Thin Layer Chromatography Stationary phase— a thin layer of coating (usually alumina or silica) on a sheet of plastic or glass Mobile phase— a liquid solvent

People of Historical Significance Francis William Aston was a British physicist who won the 1922 Nobel Prize in Chemistry for his work in the invention of the mass spectrograph. He used a method of electromagnetic focusing to separate substances. This enabled him to identify no fewer than 212 of the 287 naturally occurring elemental isotopes.