Toxicology

Vocabulary Controlled substance – a drug or other chemical compound whose manufacture, distribution, possession, and use is regulated by the legal system Drug – a chemical substance that affects the processes of the mind or body; a substance used in the diagnosis, treatment or prevention of disease; a substance used recreationally for its effects on the mind or body, such as a narcotic or hallucinogen Narcotic – an addictive drug, such as opium, that relieves pain, alters mood and behavior, and causes sleep or feelings of mental numbness

Vocabulary Poison – a naturally occurring or manufactured substance that can cause severe harm or death if ingested, inhaled, or absorbed through the skin Toxicity – the degree to which a substance is poisonous or can cause injury Toxin – a poisonous substance naturally produced by certain plants, animals, and bacteria that is capable of causing disease or death in humans; a subgroup of poisons

Toxicology The study of poisons and identification of drugs and other substances a person may use for medicinal, recreational, or criminal purposes Methods of exposure: Ingestion through gastrointestinal system Inhalation into lungs Injection into bloodstream Absorption through skin

Toxicity Depends on many factors The dose – how much taken The duration – frequency and length of exposure Nature of exposure – ingested, inhaled, absorbed Whether drug or toxin interacts with other substances in the body like alcohol or prescription drugs Many drugs indirectly toxic – substance that the drug is converted to or metabolizes to in the body is harmful

Forensic Toxicology Helps determine cause-and-effect relationship between exposure to drug and the toxic or lethal effects from that exposure Determined by chemical tests on: Body fluids Stomach contents Skin Hair Internal organs – liver, vitreous humor fluid of eye

Forensic Toxicology Toxic agents other than drugs: Heavy metals Solvents and vapors Radiation and radioactive materials Dioxins/furans Pesticides Plant and animal toxins

Toxins Also classified by how people are exposed to them: Intentionally – drugs taken to treat illness or relieve pain Accidentally – ingested or exposed, as in unintentional overdoses or harmful combinations Deliberately – suicide or exposure intended to harm or kill others

Murder by Poison Less than ½ of 1% of all homicides Commonly used poisons: Arsenic, cyanide, strychnine Also industrial chemicals created for other uses Acute poisoning – caused by high dose over a short period of time which immediately produces symptoms Cyanide ingestion or inhalation Chronic poisoning – caused by lower doses over long periods of time, which produces symptoms gradually Mercury or lead poisoning (mad hatter)

Accidental Drug Overdoses More common than death from poisoning Chris Farley John Belushi River Pheonix Jimi Hendrix Cory Monteith Whitney Houston Amy Winehouse O.D.B Jim Morrison

Drugs Illegal drugs – heroin, LSD Not accepted for medical use in U.S. Controlled substances Medications, narcotics, depressants, stimulants

Drugs: Controlled Substances Five classes: Hallucinogens Narcotics Stimulants Anabolic steroids Depressants

Hallucinogens Affect user’s perceptions, thinking, self- awareness, and emotions Plant derived: Mescaline from a cactus, Marijuana, Mushrooms Chemically manufactured: LSD, MDMA (ecstacy), PCP

Narcotics Reduce pain by suppressing the central nervous system’s ability to relay pain messages to the brain Very habit forming Opium and derivatives: heroin & codeine Hydrocodone (Vicodin, Lortab) Methadone (Dolophine) Morphine (MS Contin) Oxycodone (Percocet, OxyContin) Codeine containing – Tylenol 3

Stimulants Increase feeling of energy & alertness while suppressing appetite (caffeine, diet pills) Depression often results when drug wears off Sometimes used to boost endurance and productivity Examples: Amphetamines (speed), methamphetamines (stronger), and cocaine (including crack) Highly addictive

Anabolic Steroids Promote cell and tissue growth and division Produced in lab and have chemical structure similar to testosterone Originally produced to treat hypogonadism Now used to treat delayed puberty, impotence, muscle wasting caused by HIV Also increase body muscle and bone mass Negative effects: Mild – acne, increased body hair, baldness Severe – high BP & cholesterol, impaired fertility in males, blood clotting, kidney and liver cancers, heart attacks

Depressants Relieve anxiety and produce sleep Reduce body functions, such as heart rate, by acting on CNS Drugs like barbiturates & benzodiazepines (valium) Side effects: slurred speech, loss of coordination, state of intoxication Overdose: Slow heart rate & breathing, come and death Mixed w/ alcohol and other drugs increases risks

Alcohols All are toxic to the body Accumulation in blood may produce: Dehydration, headache, nausea, weakness Chronic abuse – liver damage Can also depress central nervous system Brain: interferes with the brain’s communication pathways, can change mood and behavior, and make it harder to think clearly and move with coordination.  

Alcohols Heart: Liver: Stretching and drooping of heart muscle Irregular heart beat Stroke High blood pressure   Liver: Steatosis, or fatty liver Alcoholic hepatitis Fibrosis Cirrhosis

Alcohols Pancreas Cancer Immune system Build up of toxic substances leading to pancreatitis Cancer Increase risk of certain cancers: Mouth, Esophagus, Throat, Liver, Breast Immune system weaken your immune system, making your body a much easier target for disease Pneumonia, tuberculosis, and weaken to warding off infections.

Other Toxins Organic Toxins – produced by living organisms interfere with that organism’s metabolism Absorbed through intestine or skin Venom – secreted toxin from an animal (i.e. bee sting, snakebite)

Other Toxins Bacterial: Botulism – most poisonous biological substance known to humans neurotoxin paralyzing muscles Extremely deadly in small amounts, can be avoided by cooking and heating food thoroughly Purified botulinum toxin – can treat muscle spasms, eye conditions, excessive sweating, headaches, promote wound healing, cosmetics (botox) Tetanus – potentially deadly nervous system disease “lock jaw”

Other Toxins Pesticides Heavy Metals used for controlling insects, mice, weeds, fungi, bacteria, viruses that threaten plants or food crops Toxic and can cause severe illness and death Examples: DDT, aldrin, dieldrin Heavy Metals Enter body by ingestion and inhalation, or by absorption Stored in soft tissues of body and can damage many organs hydrogen cyanide (gas chambers), carbon monoxide (car exhausts), potassium chloride & sodium pentothal (lethal injections), mercury (The Madhatter)

Other Toxins Bioterrorism Agents Ricin – cator bean / waste of castor oil lethal to humans in small quantities Inhaled as a mist or powder, ingested in food or drink, injected into body Prevents cells from making necessary proteins causing cell death Inhalation - death after 8 hours Ingestion - death after 6 hours

Other Toxins Bioterrorism cont… Anthrax Forms endospores Inhalation results in death Ingestion – 25-60 percent fatal Skin absorption – 20 percent untreated fatal 2001- spread through postal system and caused 22 cases (12 deaths)