In forensic science, the goal of the various scientific procedures is often to discover some fact or truth about an occurrence, often a crime. Forensic toxicology is a sub-discipline of the overarching umbrella of “forensic science.” Forensic toxicology is the study of different substances and how they break down within the body; however, forensic toxicology is particularly concerned with studying these chemical processes in relation to human deaths, often for medical or legal reasons (ABFT). Forensic toxicology uses pharmacology, clinical chemistry, and analytical chemistry to investigate deaths and interpret the results of these investigations (ABFT). According to the site “All About Forensic Science,” forensic toxicology “involves the study of the isolation and analysis of drugs and poisons from a wide variety of matrices and the effects that these may have on the individual” (All About Forensic Science).
Forensic toxicology is primarily concerned with discovering different chemicals within the human body. Many of these chemicals are contained in the blood stream, but some may be contained in hair, urine, fecal matter, skin, or any other types of human tissue (All About Forensic Science). A forensic toxicologist will run a number of tests on a sample to determine what types of substances can be found in the individual’s body, and in what quantities; these results are then analyzed by the toxicologist to determine whether or not the chemicals contained within the samples were found in high enough concentrations to be considered deadly or dangerous to the individual’s health (All About Forensic Science).
Crime televisions shows like CSI (Crime Scene Investigation) and other similar shows often portray forensic toxicologists at work, but they frequently do a poor job of correctly portraying the ways in which forensic toxicologists work. Forensic toxicologists work with small samples of blood, hair or urine that are gathered by professionals at the crime scene, and they run a battery of tests on those samples to determine how or why the person died (All About Forensic Science). Depending on the circumstances surrounding the individual’s death and the amount of decay that the body has experienced, the toxicologists may need to run tests on insects that have eaten the individual’s flesh, or other special types of circumstances (All About Forensic Science). Forensic toxicologists, then, must adapt easily to difficult situations, and must be quick to discover new techniques and new applications for tests, especially when their cases involve a death that is unusual in some significant way (All About Forensic Science).
There are many different types of tests that a forensic toxicologist can run on a sample. The types of tests run on a particular sample will depend upon the type of sample, but also the circumstances surrounding the death (All About Forensic Science). If the deceased individual was a known drug user, for instance, the forensic toxicologist may look at blood and hair samples to determine what types of drugs and what quantities of these drugs were in the individual’s system when he or she died (Ramsland). Blood is often the bodily substance used to screen for drug use, because chemicals break down predictably within the bloodstream; a sample of blood will give the toxicologist a good sense of what the individual was under the influence of at the time of his or her death (Ramsland). Some substances break down almost immediately in the blood, however; these substances may be difficult for the forensic toxicologist to pinpoint as the cause of death with only a blood sample. Samples from other tissues such as the heart, kidney, or liver may help the forensic toxicologist determine what substances were in the individual’s body at the time of death or just prior to death (Ramsland). In cases such as rape cases, drugs like Rohypnol may not be found in the bloodstream because of how quickly the drug breaks down; the toxicologist must use other techniques to uncover the mechanism of the crime (Ramsland).
In cases where blood cannot be used because of the breakdown of the chemical structure of different drugs in the body, urine is sometimes used to check for poisons, toxins, and other chemicals that are foreign to the body (All About Forensic Science). This is because the kidneys, which filter out the body’s toxins and create urine, are incredibly efficient at filtering the bloodstream; often, chemicals that do not belong in the bloodstream are expressed in the urine (All About Forensic Science). Urine can be used as an alternative to blood for some types of drug testing as well, because the kidneys are such an effective filtering system for the human circulatory system (All About Forensic Science).
The other place that a forensic toxicologist may look for evidence of long-term drug use or poisoning is in the hair. Because hair grows slowly, long-term use of a substance is frequently expressed in the hair, in the same way that a tree’s rings will tell the keen observer about the climatic conditions of the year that the ring was formed (All About Forensic Science).
Forensic toxicologists have a difficult job, because they often have to deal with the natural processes of the body as it tries to break down foreign chemicals that enter it. Toxicologists are fighting against time and nature, and using the clues that they discover through different scientific tests to analyze and decide the facts of a particular case (ABFT). Forensic toxicologists and forensic science in general is not concerned with guilt, innocence, or the justice system, although they are an integral part of it-- instead, forensic science is concerned with discovering all the facts of a particular case and presenting it clearly and cleanly (All About Forensic Science).
ABFT. "American Board of Forensic Toxicology." 2004. Web. 19 Jul 2013. <http://www.abft.org/>.
All About Forensic Science. "Forensic Toxicology Information Guide." 2013. Web. 19 Jul 2013. <http://www.all-about-forensic-science.com/forensic-toxicology.html>.
Ramsland, Katherine. "Forensic Toxicology, how it solves cases and the major cases it solved." 2003. Web. 19 Jul 2013. <http://www.trutv.com/library/crime/criminal_mind/forensics/toxicology/index.html>.
Science Daily. "Forensic toxicology." 2012. Web. 19 Jul 2013. <http://www.sciencedaily.com/articles/f/forensic_toxicology.htm>.
The International Association of Forensic Toxicologists. "About TIAFT." 2013. Web. 19 Jul 2013. <http://www.tiaft.org/>.