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• Forensic toxicology is examined in Chapter 9.

Toxicology Overview

• Technological advances improved the identification of toxic substances.
• Recovered substances are processed, weighed, separated, and finally identified.
• Illegal drugs are a major source of crime in the US.
• Exposure to toxins and poisons can be natural or by suicide attempts/crime.
• Forensic toxicology is used to determine the relationship between substance exposure and its toxic/lethal effects.

Toxicity

• Toxicity depends on dose, duration, nature of exposure, interactions with other substances like medications, and by-products of metabolism.
• Exposure to toxic substances may occur naturally, intentionally, or deliberately, including arsenic, mercury, lead, toxic gases, pesticides, herbicides and radiation.
• Drugs can affect a person's health, mood, metabolism, reality perception, and awareness.
• Extended drug use may lead to drug tolerance, dependence, addiction, health issues, brain damage, criminal behavior, or even death.
• Lethal gases can damage the nervous system and interfere with breathing.
• Substance evidence collection, processing, and handling require established guidelines.

Science of Neurons

• Neurons, also called nerve cells, have spaces between them called synapses.
• Neurotransmitters are chemical messengers used to transmit a message between neurons.
• Drugs can interfere with nerve transmission by blocking or mimicking neurotransmitters.
• The most amount of a helpful drug without causing dangerous side effects is called the maximum tolerated dose.
• Taking too much of a drug or a dosage that is too high can exceed the tolerated maximum and have dangerous consequences.

Common Terms Defined

• Toxicology is the study of drugs, toxins, poisons, metabolites, and other substances which can harm a person.
• This occurs when used for recreational, medical, or criminal purposes.
• Poisons include natural or manufactured chemicals that can cause great harm.
• Arsenic and rat poison are considered to be poisons.
• Toxins are naturally-occurring, poisonous substances produced by living things like rattlesnake venom or ricin.

Intake Types

• Intentionally taken drugs treat pain or illness.
• Accidentally taken drugs are unintentionally consumed.
• Deliberately taken drugs are consumed to commit suicide.

Body Fluids

• Body fluids are used to detect substances in both living people and the deceased.
• Fluids used include blood, sweat, stomach contents, and the vitreous humor of the eye.
• Metabolites are isolated to verify their presence in the body.

History of Forensic Toxicology

• Socrates was one of the earliest reported victims of poisoning in 399 B.C. with Hemlock.
• Poisoning became an occupation by the 1600s.
• Eliminating enemies through poisoning was a means for the wealthy to settle disputes.
• Arsenic became known as inheritance powder.
• Arsenic is extremely toxic even in small doses.
• It is odorless and tasteless, and mimics natural disease symptoms.
• Chemical analysis methods were developed in the 1800s to recognize poisons in tissue.
• Standardized testing and techniques were developed in 1980 to determine cause of death.
• The FDA was formed in 1959.
  • The FDA's purpose is to protect the public from foods, drugs, or cosmetics with toxic contents.
• The Controlled Substances Act was passed by Congress in 1970.
  • This established penalties for possession, distribution, and use of drugs.
• Less than 0.5% of homicides today are a result of poisoning.

Detection, Collection, and Storage of Evidence

• Evidence may be in pill, powder, or liquid form, and also include botanical matter, methamphetamine crystals, or urine, blood, or saliva.
• Luggage, boxes, and shipping containers can transport drugs, poisons, and toxins, though drug-sniffing dogs are trained to detect them.
• Mules smuggle drugs and may hide them by swallowing or in body cavities.
• Mules may die as a result.
• Packaging evidence properly is crucial for preservation and protecting individuals working with the evidence.
• All plant matter (ie. Marijuana) and wet items like those with blood stains should be dried and stored in paper bags to prevent mold or contamination.
• Biohazard-labeled glass containers should be used for syringes with needles.
• Evidence identified that is hazardous and volatile is handled with extreme caution, and only small amounts are collected.

Evidence Testing

• A toxicologist needs to identify the substance/s present through qualitative testing.
• A toxicologist needs to detect illegal components.
• A toxicologist needs to measure the amount of each substance present by way of quantitative testing.
• Presumptive testing may be done at crime scenes to provide preliminary tests.
• These tests do not give positive identification, and may involve colometrics and microscopic examination.
• Confirmatory testing is a detailed process which positively identifies the substance.
• Toxicologists must distinguish between acute poisoning and chronic poisoning.
  • Acute poisoning is a high dose over a very short period.
    • Ingestion of cyanide creates immediate symptoms.
  • Chronic poisoning is lower doses over time, and produces symptoms gradually.
    • Mercury and lead poisoning are examples of chronic posioning.

Vocab

• Key terms include: addiction, illegal drug, controlled substance, hallucinogen, Controlled Substance Act, depressant, dependency, toxin, narcotic, poison, toxicology, stimulant, tolerance, and toxicity.

Drug Schedules

• Illegal drugs have no current medical use.
  • Heroin and LSD.
• Controlled substances are restricted due to their effects, the potential for abuse, and how easily someone can become dependent.
  • Stimulants, depressants, anabolic steroids, and some narcotics.
• The federal controlled substances act of 1970 recognizes five schedules of drugs.

Heavy Metals, Gases, Toxins, and Poisons

• These metals may enter the body by ingestion, absorption from the skin or mucous membranes, or inhalation.
• The soft tissues store these heavy metals, which can damage organs.
• Arsenic has been known for contaminating drinking water.
• Mercury poisoning can result from industrial waste in water sources.
• Lead was once an ingredient in paint.
  • Children suffered from lead poisoning when they ate lead paint chips.

Symptoms of Heavy Metal Overexposure

• Symptoms of lead and mercury poisoning, and arsenic exposure are included in Figure 9-4.

Lethal Gases and Lethal Injections

• Nazis used lethal gas chambers during WWII, resulting in the deaths of millions with carbon monoxide or hydrogen cyanide.
• American penal systems use hydrogen cyanide as a death penalty.
  • A gas chamber is a dangerous and complicated method, and works by blocking the body to use oxygen.
• Accidental deaths can occur by carbon monoxide gas interfering with the body's oxygen absorption.
• The death penalty/capital punishment uses injections of potassium chloride or sodium pentothal.
  • Potassium chloride affects the electric signals to the heart.
  • Sodium Pentothal is a depressant that slows the central nervous system.

Pesticides and Herbicides

• The longer the exposure, the more severe the symptoms.
• Common symptoms are included in Figure 9-5 from pesticides such as Glyphosate Mixture and Aldrin or Dieldrin.

Toxins

• Toxins may be produced by plants or animals.
  • Ricin and rattlesnake venom.
• Reactions to various toxins can be different in people.
• Some will go into shock from a simple insect bite, while others will only feel minor skin irritation.
• There is no way of knowing how someone can be affected without exposure to the toxin.
• The toxins of interest to forensic toxicologists includes poisonous substances to humans.

Drugs and Crime

• Drugs were not always bad, and were intended to prevent, treat illnesses, and reduce pain.
• Almost 50% of federal prisoners are imprisoned for substance-related offenses.
  • Possession or distribution of illegal drugs.
  • Drug-related offenses contribute to the crime
  • Drug-using lifestyle increased risk of involvement in illegal activities.
• Over $600 billion annually is spent on crime, lost work productivity and healthcare as a result of substance abuse.
• Continued use of a substance can lead to dependence and addiction.
• Drugs are divided into five classes based on the reactions they produce.
• Reaction to drugs cannot be predicted because chemistry is different for everyone.
• People may be taking food, alcohol, or another substance which differs the interaction.

Drug Tolerance

• Drug tolerance builds up with consistent drug use so more of it is needed to produce the same effects.
• Continued use may result in addiction, also know as a physiological need.
• Stopping drug use suddenly may result in physical withdrawal symptoms.
• Drug dependency results in an intense craving for the substance.
• Dependency differs from addiction because dependency will not result in the physical withdrawal when ceasing the drug.

Schedules of Drugs

• Schedule I drugs have a high potential for abuse and no medical use: – Examples include Heroin, LSD, peyote, MDMA (ecstasy), bath salts, and marijuana.
• Schedule II drugs have a high potential for abuse and severely restricted medical use: – Examples include cocaine, methamphetamine, methadone, and oxycodone.
• Schedule III drugs have an accepted medical use and a moderate potential for abuse, along with a moderate to low risk of dependence: – Examples include: Barbiturates, ketamine, and steroids. – Barbs are used to treat insomnia, anxiety, and seizure disorders, and have been superseded by Benzos.
• Schedule IV drugs have a low potential for abuse, medical use, and its use provides a risk of dependency: – Examples include sleeping pills, other tranquilizers, and Xanax or Valium.
• Schedule V drugs are widely used for medical reasons, and have a very low potential for abuse which contains a limited number of narcotics: – Examples include Tylenol with codeine and Robitussin AC.

Illegal Drugs

• Hallucinogens may cause dilated pupils, and increase heart rate and blood pressure.
• In terms of effects, hallucinogens alter perception, thinking, and self-awareness, which can be “colorful” or make things appear “3-dimensional.”
• Flashbacks, even life-long trips may occur long after the drugs wear off.
• Narcotics are addictive, sleep-inducing drugs that act as central nervous system depressants, and suppress pain. – There can be withdrawal symptoms, and is highly addictive, making recovery a challenge.
• Methadone is a slow-acting opioid agonist that is used orally and reaches the brain slowly, diminishing the “highs," and helps prevent withdrawal symptoms.
• Methadone has been used since the 60’s to treat heroine disorders and is an effective option for patients that do not respond to other medications. – A certified outpatient treatment program dispenses daily doses to drug users.
• Combining drugs, such as heroine and alcohol can have fatal effects because they can amplify the depressant effects.

Overdose Characteristics of Hallucinogenic Drugs

• Figure 9-8 shows the characteristics of hallucinogenic drugs such as LSD, mescaline, marijuana MDMA, PCP, psilocybin, and synthetic marijuana.

Controlled Substances

• Stimulants are highly addictive and suppress appetite while increasing energy and alertness.
• Amphetamines and cocaine are stimulants that increase productivity and endurance.
• Extreme cases of side effects include high blood pressure, heart rate, and brain bleeding. – Depression usually follows after drug use fades off.
• Legal opiates like codeine, morphine, and milder painkillers compose narcotics.
• Hydromorphone is a strong, synthetic opiate given for major pain and can cause long-term addiction.
• Addiction can be diagnosed from low blood pressure, weakness, confusion, loss of consciousness, breathing issues, dizziness, and even a coma.
• Barbiturates and benzodiazepines are depressants that induce sleep and are very addictive
• Alcohol and combining substance with depressants may lead to accidental or suicidal deaths
• Abrupt substance withdrawals, including alcohol, could lead to death

Alcohol

• One nervous system depressant is alcohol
• Alcohol is expressed as a percentage by volume or in proof, which is twice the percentage
• An 80 proof liquor is 40% alcohol
• Someone that has a .15% BAC will store alcohol in their body for around ten hrs
• Acetaldehyde is a toxic element that caused by the liver processing alcohol and then to the acetic acid, which gives toxic hangover effects
• Liver failure is common for alcoholics
• One serving of alcohol can be managed by the the rate alcohol is processed
• High alcohol consumption increases the blood alcohol level along with its effects
• Alcohol may also be detected in someone's breath test
• Breathalyzer measures alcohol amount to test BAC, but is .08 (in some states may be less)

Anabolic Steroids

• Muscle and tissue growth is promoted thru anabolic steroids
• Chemically, these have similar structure to testosterone
• Anabolic steroids can be used for hypo-gonadism, where testes generate lower testosterone; muscle deterioration brought by cancer, HIV, and other diseases; delayed puberty; impotence.
• Weightlifters and bodybuilders used it to rapidly gain bone and muscle mass thru the 30’s.
• Negative effects include aggression, acne, baldness, high cholesterol, high blood pressure, blood clotting, kidney and liver cancer, heart problems, and sexual problems.

Doping

• Doping uses substances in order to improve athletic performance
• Most organized events ban doping for unfair “spirit of competition” against nonusers to boost athleticism
• Doping can lead to desperate athletes to doping to win
• Athletes are routinely tested for drug usage
• Students should be tested routinely for drug usage