FT PRESENTATION

Forensic toxicology is the study of poisons and their effects on the body in relation to the law. It involves testing for toxic substances in cases of intoxication or drug poisoning. Toxicology itself refers to the science of poisons, including the analysis, detection, and effects of toxins on the body. Drugs and toxins can cause harm or death depending on various factors, such as dosage and how they enter the body. Forensic toxicologists use specialized tests and equipment to determine the presence of toxic chemicals in cases involving homicide, suicide, DUI, and more. The history of forensic toxicology dates back to the 19th century, with advancements in testing methods and the detection of substances like arsenic. It is divided into three sectors: workplace testing, post-mortem toxicology, and drug effect on human performance. Workplace testing includes drug screening for employment and testing in suspicious behavioral cases. Post-mortem toxicology is performed during autopsies to d The world is filled with various types of poisons. Primarily derived from plants, poisons are substances that can affect the human condition, have been used around the world for centuries. With the good aspect of these substances comes the negatives. The positive effects of the drugs lead to substance abuse and with the access to various poisons and toxins, murder cases involving them are not uncommon. 75% of evidence analyzed in forensic laboratories is drug related in the United States. Now there is an ever-growing necessity for additional crime labs and the expansion of already existing ones. Not only that, time spent on drug related crimes is a major distraction from evaluating other types of crimes. Forensic toxicology is very important to forensic science because of the widespread use of drugs. Hi, my name is Gabrielle Gamble and today we'll be talking about forensic toxicology. Let's start off with a simple question. What exactly makes something a poison? Is a substance that's dubbed a poison? Well, sometimes yes. However, it is not the substance itself but the dosage of said substance that makes it a poison. As physician and chemist Per Seltzer stated, all substances are poisons. There is none which is not. The right dose differentiates a poison and a remedy. This concept is called hormesis and it is seen in everyday life. Take arsenic for example. It is commonly ingested through food and water since it is a naturally occurring substance. What makes arsenic deadly is if too much is ingested in a small time frame. Now that we've defined what a poison is or really what makes something a poison, we're going to go over some history. The earliest recorded use of a poison was in 339 B.C. when Socrates was executed using an extract of hemlock. During the European Renaissance, poisoning became an art, hobby, or even an occupation. The most common poisons were derived from hemlock, monk's chud, belladonna, and toxic metal salts such as arsenic. Arsenic was of prevalent use because not only was it practical to use and easy to obtain, symptoms of arsenic poisoning resembled, if not mirrored, symptoms of death by natural causes. Forensic toxicology is simply toxicology applied to the law. So before we talk about forensic toxicology, we need to discuss toxicology itself. Toxicology refers to the science of poisons. A toxin is a substance that is capable of causing injury or death to the health of a living thing upon contact or absorption. The level of toxicity someone suffers from depends on many factors including the dosage, chemical or physical form of the substance, how it entered the body, body weight of the victim, and physiological conditions of the victims, period of exposure, and whether other chemicals are present in the body or in the dose. Now that we've talked about toxins, we move on to drugs. Now, a drug itself isn't really considered a poison. However, drug overdoses fall under the category of poisoning. The term drug refers to a natural or synthetic substance that is used to produce physiological or psychological effects on humans or other high-order animals. Drugs can mean different things to individuals. Sometimes they are needed to live. Sometimes they are needed to die. Drugs of habit-forming properties were of the most concern by law in the early 20th century. There are two types of drug dependence, psychological and physical. Psychological dependence refers to when the drug is allowed for the use of underlying emotional needs. Physical dependence is brought on by psychological dependence, specifically when the individual takes the drug in a consistent pattern and when that pattern is broken, the body reacts. When the physical dependence or addiction stage is reached, once the drug is no longer being taken, the body will experience withdrawal sickness. Symptoms of withdrawal sickness include vomiting, chills, insomnia, pain, cramps, and hallucinations. Drugs have two main categories, controlled drugs and illicit drugs. Controlled drugs are mandated by law, which is defined by the Controlled Substance Act. Meanwhile, illicit drugs refer to those not controlled by the law, which are mostly considered illegal. There are four types of illicit drugs, narcotics, hallucinogens, depressants, and stimulants. Narcotic drugs are a type of analgesic drug that acts as a painkiller that can depress vital body functions such as blood pressure, pulse rate, and breathing rate. Analgesic drugs relieve pain by depressing the nervous system. Examples of this drug include morphine, heroin, methadone, and codeine. Hallucinogens refer to substances that can affect mood, attitude, thought process, and perceptions. Examples of this drug include marijuana, LSD, and phencyclidine. Depressants refer to a substance that can depress the central nervous system's functions. They can calm anxiety and irritability and cause sleep. Some examples are barbiturates, alcohol, and diazepam. Lastly, stimulants are substances that can increase alertness or activities. Examples of this drug include amphetamines, cocaine, caffeine, and nicotine. Now that I've talked about toxicology, we can move on to the subject of this presentation, forensic toxicology. As I explain later, toxicology refers to the science of poisons. This covers the analysis, detection, and effects of poisons on the body as well as methods used to treat them. Forensic toxicology is a combination of toxicology with matters regarding the law. These legal aspects refer to homicide, suicide, road traffic, DUI, and so on. The job of a forensic toxicologist involves testing for the presence of toxic gases, illegal or medicinal drugs, toxins, liquor, metal or elements, and other toxic substances when intoxication or drug poisoning seems to be the cause of death or of a particular behavior. Through the use of highly specialized tests, methodologies, equipment, chemical and biomedical instruments, and chemical reagents, forensic toxicologists will determine the presence or absence of toxic chemicals. Now that I've talked about what forensic toxicology is, we are going to discuss its history. The earliest progressions of forensic toxicology were achieved in the 19th century. In 1814, Matthew Orfila published the first study to approach chemistry and potions using a systematic method. I'm not even going to try and say that. Later in 1836, chemist James Marsh produced a very sensitive and reliable test to detect the presence of arsenic in the body, tissues, and fluids. The first case to employ this test was the Marie Lafarge case of 1840. Marie Lafarge's husband died shortly after eating a piece of cake. The couple's maids had testified that Marie had added a white powder to her husband's drink. It was revealed that she had purchased arsenic oxide from the local pharmacy. The husband's body was tested and initially it lacked any signs of poisoning. The food in the Lafarge house was then tested and arsenic was detected. The body was tested again and arsenic was found this time. Marie was given a life sentence in prison and passed away in 1852. Forensic toxicology is composed of three sectors, workplace or pre-employment testing, post-mortem toxicology, and drug effect on human performance. Workplace or pre-employment testing covers drug screening, tests required by a workplace before employment, or the use of a drug test when someone is acting strange and drugs are suspected to be the cause of that behavior. Post-mortem toxicology refers to testing on a deceased person as a part of the autopsy process to establish whether a drug or a poison was a cause of death or a contributing factor. Lastly, human performing testing, also called criminal toxicology, involves testing to convey the presence or absence of substances affecting human behavior and performance. This includes DUI, committing crimes while on a drug, criminal offenses, and so on. Workplace testing consists of two divisions of practice, regulated testing and non-regulated drug testing. Regulated drug tests are enforced by the government and are mandatory for specific jobs such as drivers, all employees of the government, and military employers. Non-regulated drug testing covers any drug testing that is requested by the workplace itself to be employed. The typical bodily specimen collected for workplace drug testing is a urine sample. However, in other countries, sometimes it is required to have an additional sample, such as a blood, oral fluid, or hair sample, and human breath testing may also be employed. Post-mortem toxicology is an assessment of a higher difficulty due to the fact that for a body to have a proper evaluation, it must have been autopsied at a reasonable time frame and protected from harsh conditions of the environment. To identify drugs in a dead body, tests will search for the metabolisms of drugs. For these metabolisms to linger, the body must be preserved. Post-mortem toxicology searches for the drugs using a variety of samples such as urine, blood, gastric contacts, vitreous, and tissues including the kidney, liver, spleen, muscle, and brain tissues. The type of sample collected is based on the condition of the body and the amount or type of chemical the body contains. The identity of the drugs and the amount present must be determined. The decomposition state of the body also should be taken into account. Human performance testing determines how an individual acts under the influence of a substance or drug of abuse. Here, blood is mainly used as a specimen due to the fact that it can be used to establish the presence of a drug, but also can help establish the time frame of drug intake or exposure. There are two phases of testing, screening or initial testing and confirmatory testing. Screen testing or initial testing is done by using immunoassay methods. This will be done for a specific class of drugs, particularly opiates, amphetamines, benzodiazepines, and so on. Tests will be conducted to convey whether the sample is negative or non-negative. Each country's governmental regulatory bodies have their own ranges for determining a sample is negative or non-negative. Confirmatory testing is the next step of the process. It is performed as mass spectrometry by detector alone, by detector alone with the chromatography technique, which chemically separates analytes. Now we're going to discuss a case example. On September 10, 1978, dissident Bulgarian writer George Markov was assassinated by the agents of the Bulgarian secret police. This was the murder weapon. Wait, wait, wait, before your brain explodes, let me explain. Three days earlier, he had been on the Waterloo Bridge when a foreigner had jabbed him in his right thigh with the tip of their umbrella. What Markov thought was a harmless interaction led to his death three days later. When the autopsy was performed, a small platinum iridium pellet, 1.7 millimeters in diameter, was found in the same location he had been jabbed by the umbrella. The pellet notably had two holes drawn into it in which a poison was supposedly placed. Written became the suspected poisons and as little as two milligrams could have been used. They were never able to catch the individual that killed him. I know you're thinking that this is a very big leap of logic, but this did happen to somebody else previously, but that person had survived because the bullet that they received in their body or whatever, I don't remember exactly where, didn't hit a major vein. They think that's why that person lived, but he, Markov, wasn't as lucky. Poisons have always been a substance used for murder, but there is nothing to combat this matter until the 19th century. Although any substance in the world can be considered a poison, it is the dose that determines the fate of the organism that receives it. Forensic toxicology consists of four sectors, each dealing with a period of human condition that may have been affected by drugs. Each sector has its bodily samples referred to take for testing. With these samples, screenings and confirmatory tests will be performed to determine the amount of drugs in the individual's system. With the rise of crimes related to drugs and the effects that drugs have on people which could lead to abnormal and dangerous actions, forensic toxicology has remained an important component of forensic science. Thanks. I'm done. Thank you. I can stop this. I can stop this now.