Forensic Toxicology - PowerPoint PPT Presentation

forensic toxicology n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Forensic Toxicology PowerPoint Presentation
Download Presentation
Forensic Toxicology

play fullscreen
1 / 15
Forensic Toxicology
154 Views
Download Presentation
xylia
Download Presentation

Forensic Toxicology

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. Forensic Toxicology By Kaitlin Cassity

  2. "All substances are poisons; there is none which is not a poison. The right dose differentiates a poison and a remedy." Paracelsus (1493-1541)

  3. Case Study: Viktor Yushchenko (2004) • During the 2004 Ukrainian presidential election, Viktor Yushchenko announced his decision to run as an independent candidate against Prime Minister Viktor Yanukovych. • Upon becoming seriously ill, with his face pale and heavily disfigured, Viktor claimed his illnesses were caused by actions taken by government officials. • Austrian doctors confirmed the independent candidate was in fact poisoned with TCDD dioxin, with more than 1000 times the usual dioxin concentration within his body. • Symptoms began after Yushchenko attended a dinner with leaders of the secret Ukrainian police. Yushchenko began vomiting violently, eventually becoming paralyzed within his face, unable to speak or read. He developed a severe backache and stomachache as well, most significantly, developing a serious condition that left his face scarred and disfigured. • Dioxin, the name given to a group of related toxins which can cause cancer and even death, was identified through thorough toxicological analysis. As a organic compound, dioxin is known to cause reproductive and developmental problems as well as extreme skin eruptions. From both screening and confirmation testing and observing Yushchenko’s symptoms and concentrations of the substance within his body, toxicologists were able to identify the harmful substance. • Investigations held by the Ukrainian Security Service and Prosecutor-General’s Office are still underway, with no definite results. Nevertheless, the identifying of the proper substance and how it was administered to the victim, is crucial in identifying the proper criminal. Investigators continue to utilize toxicological analyses to link other significant factors of the case, specifically the location, time, probable suspects etc. together.

  4. General Information:What is forensic toxicology? • Forensic toxicology is the analysis of alcohol, drugs, and poisons in body fluids, in the hope to produce results beneficial to courts of law. Toxicologists study the “adverse effects of chemicals on living organisms.” (www.apsu.edu) Foreign chemicals are detected in the human body and identified. • Toxicologists perform an array of tasks and may specialize in a variety of areas, specifically descriptive toxicology, mechanistic toxicology, and regulatory toxicology.

  5. "The Coroner's Chemist:"The Forensic Toxicologist • Forensic toxicologists are most simply physicians who utilize chemical analysis and apply it to an investigation of criminal poisoning. Toxicologists must be familiar in biochemistry, physiology, pharmacology, chemistry, and pathology. • Toxicologists study the context of an investigation and determine if and what toxic substances are present, the concentrations of those substances, and the possible effects of those chemicals upon the human body. • Toxins, materials that yield life-threatening effects, are difficult to determine within the body. Thus, toxicologists conduct specific tests in hope of accurately classifying the substance. Tests include preliminary acid-base procedures, screening tests, and confirmation tests.

  6. "The Coroner's Chemist"(Continued) • Toxicologists pay close attention to the dose-response relationship, which describes the change in effect within an organism as levels of exposure to a stressor (chemical) differ. Dose-response relationships can apply to both individuals as well as populations. In the studying of dose response, forensic toxicologists are able to determine “safe” versus “hazardous” levels of substances in relation to the human body.

  7. Poisonous Substances and Their Effects • The degree to which a substance is poisonous or can cause injury depends on the dose, the duration, the nature of the exposure, and the substances interactions with other chemicals within the body. • Toxins include controlled substances, organic toxins, alcohols, bacterial toxins, heavy metals and pesticides, and bioterrorism agents. Controlled substances include narcotics, stimulants, anabolic steroids, and depressants. • Persons can become exposed to toxic substances intentionally, accidentally, and deliberately.

  8. Poisonous Substances and Their Effects(Continued) Most Frequently Reported Poisons Most Frequent Deaths by Poisoning • 1. Household cleaning supplies • 2. Analgesics (aspirin) • 3. Cosmetics • 4. Cough and Cold Remedies • 5. Plant scrapes/insect bites • 6. Pesticides • 7. Topical creams and lotions • 8. Hydrocarbons (gasoline, kerosene) • 9. Anti-microbacterial soaps • 10. Sedatives/hypnotics/antipsychotics • 11. Food poisoning • 12. Alcohol • 1. Antidepressant medications • 2. Analgesics (aspirin) • 3. Street drugs • 4. Cardiovascular drugs • 5. Alcohol • 6. Gases and fumes • 7. Asthma therapies • 8. Industrial Chemicals • 9. Pesticides • 10. Household cleaning supplies • 11. Anticonvulsant medications • 12. Food, plants, and insects

  9. Detecting and Classifying Poisonous Substances • Initially, the forensic toxicologist is given samples of body fluids, stomach contents, and organ parts. With access to a coroner’s report, the toxicologist is able to observe varioussymptoms of the corpse. Specimens of the drug are divided into fractions, acidic and basic.   • The specific tissue or fluid sample is then classified as a drug sample and is screened and confirmed through a series of tests. Screening tests process specimens for a wide range of toxins in a short period of time. Positive results of screening tests must be proven accurate by a confirmation test.

  10. Screening Tests • Screening tests aid in determining a specific type of toxin within the body. Tests include: • Physical tests-boiling point, melting point, density, and refractive index • Crystal tests-treatment with chemical reagent to produce crystals • Chemical spot tests-treatment with a chemical reagent to produce color changes • Chromatography- (thin layer of gas created): components of mixture are separated

  11. Confirmation Testing:Common Drugs and Their Side Effects • Mass Spectrometry- Each toxin has a known mass spectra or “fingerprint,” which is infallible proof of its presence within the human body. By observing the results of the screening tests, toxicologists are able to determine what type of substance is present. • Drug overdoses as well as alcoholic poisoning cases are most complex for forensic toxicologists, thus Drug RecognitionExperts and other professionals evaluate alcohol intoxication measurements. • Acids (nitric, hydrochloric, sulphuric): Burns around mouth, lips, nose • Aniline (hypnotics, nitrobenzene): Skin of face and neck quite dark • Arsenic (metals, mercury, copper, etc.): Severe, unexplained diarrhea • Atropine (Belladonna), Scopolamine: Pupil of eye dilated • Bases (lye, potash, hydroxides): Burns around mouth, lips, nose • Carbolic acid (or other phenol): Odor of disinfectant • Carbon monoxide: Skin is bright cherry red • Cyanide: Quick death, red skin, odor of peach • Food poisoning: Vomiting, abdominal pain • Metallic compounds: Diarrhea, vomiting, abdominal pain • Nicotine: Convulsion • Opiates: Pupil of eye contracted • Oxalic acid (phosphorous): Odor of garlic • Sodium fluoride: Convulsion • Strychnine : Convulsion, dark face and neck

  12. Expert Tells All: Dr. Alan Barbor • With thirty years of experience in forensic toxicology and clinical laboratory science, Dr. Barbor has contributed to 200 Justice, Municipal, Superior, and U.S. District court cases.   • Dr. Barbor provides drug and alcohol testing in service of the courts. “Our work is primarily for coroners and the police, with some for defense attorneys and other clients.” • Dr. Barbor feels as though his job, although not “infrequently, can help society at large as well as individuals. Sometimes I can help to prove, right, or ameliorate injustice, which I can feel good about for a very long time.” • The job is described as not always easy as the “hours can be long.” However, Barbour feels that it is merely a matter of choice, living by the words, “more people rust out than wear out.” The least enjoyable element of his job involves cleaning “up the mess when coroner’s offices send us leaking, inadequately packaged, fermenting samples.”

  13. Qualifications? • Dr. Barbor started out his college career as a Chemistry major, enjoying organic chemistry. He states he wanted to do something “socially useful, to live in my native state and make use of my education in some way.” From the help of a PhD chemist, Barbor followed his mentor into medical laboratory technology. He continued gaining qualifications and experience and eventually was introduced to forensic toxicology labs, which were often divisions of medical labs. He currently works in both fields, “although the proportion varies.” General Qualifications Necessary • Bachelor’s degree in Chemistry or a related field • Expert in analytical chemistry • Practical experience in a forensic toxicology laboratory • Master’s degree/ PhD in one of the natural sciences not always necessary • American Board of Forensic Toxicology certification

  14. Applying Forensic Toxicology in the Work Place • Toxicologists can provide their skills to a multitude of organizations. Some of the most common agencies are listed below. • Food and Drug Administration: Responsible for regulation drugs, medical devices, cosmetics, and acceptable daily intake of food additives. • Environmental Protection Agency: Regulates pesticides, toxic chemicals, hazardous wastes and toxic pollutants in water and air. • Occupational Safety and Health Administration asks toxicologists to determine if chemicals in the workplace air is below threshold limit value. • Consumer Products Safety Commission

  15. Resources • http://www.globalsecurity.org/wmd/library/news/ukraine/ • http://www.apsu.edu/ • http://home.lightspeed.net/~abarbour/cv.htm • http://www.soft-tox.org/ • http://www.tiaft.org/ • http://en.wikipedia.org/wiki/Toxicology • http://www.guardian.co.uk • Bertino, Anthony. Forensic Science: Fundamentals & Investigations; Chapter 9: Drug Identification and Toxicology (p250-262).