Chapter 9 Drug Identification and Toxicology Toxicology is the study of poisons & id of drugs Most people are exposed to drugs by ingesting, inhaling, injecting, or absorbing Forensic Science: Fundamentals & Investigations, Chapter 9

Introduction Forensic toxicology helps determine (a) the cause-and-effect relationships between exposure to a drug or other substance and (b) the toxic or lethal effects from that exposure. People can be exposed to toxic substances: intentionally—by treating illness or relieving pain accidentally—by harmful combinations or overdoses deliberately—by harming or killing others or by committing suicide Forensic Science: Fundamentals & Investigations, Chapter 9

Poison—Murder, Accidental Overdoses, and Drug Offences Less than ½ of 1% of all homicides results from poisoning. Accidental drug overdoses are more common. More than 50% of the federal prison population and about 20% of the population in state prisons consist of drug offenders. Acute vs. chronic poisoning Forensic Science: Fundamentals & Investigations, Chapter 9

Controlled Substances—Hallucinogens The effect and intensity of response to these drugs varies from person to person. Often derived from plants, hallucinogens affect the user’s perceptions, thinking, self-awareness, and emotions. Affects of an overdose include an increased heart rate, often increased blood pressure, and sometimes panic attacks, anxiety, or psychosis. Forensic Science: Fundamentals & Investigations, Chapter 9

Plant derived: mescaline (peyote), marijuana, mushrooms Man-made: LDS, MDMA, PCP Forensic Science: Fundamentals & Investigations, Chapter 9

Controlled Substances—Narcotics Narcotics reduce pain and can be very habit forming. They suppress the CNS ability to relay pain messages Ex: opium (herion ,codeine) Man-made: hydrocodone, methadone, morphine, oxycodone Forensic Science: Fundamentals & Investigations, Chapter 9

Controlled Substances—Stimulants Stimulants increase feelings of energy and alertness while suppressing appetite. As the drug wears off, however, depression often results. Affects of an overdose can include high blood pressure, agitation, confusion, or seizures. Stimulants tend to be highly addictive. Forensic Science: Fundamentals & Investigations, Chapter 9

Controlled Substances—Anabolic Steroids These drugs are produced in a laboratory and have a chemical structure similar to testosterone. Anabolic steroids promote cell and tissue growth increasing bone mass and body muscle. Because of this they are popular with weightlifters, bodybuilders, and other athletes. What are some of the negative side effects that are possible? Forensic Science: Fundamentals & Investigations, Chapter 9

Controlled Substances—Depressants Depressants act on the central nervous system and increase the activity of a neurotransmitter called GABA. Increased GABA production results in drowsiness and slowed brain activity. These drugs, consequently, relieve anxiety and produce sleep. Mixing depressants with alcohol and other drugs increases their effects and health risks, possibly leading to coma and death. Forensic Science: Fundamentals & Investigations, Chapter 9

Controlled Substances—Alcohols Methanol turns to formaldehyde in liver Grain alcohol - ethanol - fermentation of sugar, fruits and grains - pure ethanol can damage tissue Ethanol converts to acetaldehyde then acetic acid Depresses CNS Forensic Science: Fundamentals & Investigations, Chapter 9

Controlled Substances—Bacterial Toxins Tetanus Lockjaw, as it is sometimes called, is produced by the Clostridium tetani bacteria. Its poison can cause violent muscle spasms. Botulism Produced by the bacteria Clostridium botulinum, botulism paralyzes muscles. It causes irreversible damage to nerve endings. Very small amounts are extremely deadly. Botulism is the most poisonous biological substance. Forensic Science: Fundamentals & Investigations, Chapter 9

Heavy Metals and Pesticides Metal cmpds like arsenic, lead and mercury are very poisonous. Used in suicide and homicide Ingested, inhaled, absorbed Metals are stored in soft tissues-damage organs Forensic Science: Fundamentals & Investigations, Chapter 9

Controlled Substances—Pesticides and Heavy Metals Pesticides mostly are used to protect plants or food crops. Metal compounds are very poisonous. Forensic Science: Fundamentals & Investigations, Chapter 9

Controlled Substances—Pesticides and Heavy Metals Metal compounds can damage many organs in the body. Forensic Science: Fundamentals & Investigations, Chapter 9

Controlled Substances—Bioterrorism Agents Ricin is a poisonous protein in the castor bean. is lethal in extremely small amounts. can enter the body in various ways: inhaled as a mist or a powder. ingested as food or drink. injected into the body. can cause death within a few hours. Forensic Science: Fundamentals & Investigations, Chapter 9

Controlled Substances—Bioterrorism Agents Anthrax is caused by the bacteria Bacillus anthracis, which forms spores. can be spread to humans from infected animals. can enter the human body through: inhalation; causing breathing problems that usually result in death. ingestion; becoming fatal in 25% to 60% of cases. absorption via the skin; leading to death in about 20% of untreated cases. Forensic Science: Fundamentals & Investigations, Chapter 9

. . . . . . . . . . . . . . . . . Summary Forensic toxicology seeks to identify poisons or drugs in criminals and victims. Toxicology is important in studying cases of drug overdose and sporting violations. Controlled substances fall into five main groups. Poisons can be produced by living organisms. Pesticides and heavy metals are common poisons. Bioterrorism agents include ricin and anthrax. Forensic Science: Fundamentals & Investigations, Chapter 9