Forensic Toxicology

Forensic Toxicology

            In forensic science, there is a specific specialty to analyze and identify the use of toxins or drugs in a victim's body or anywhere at a crime scene, and with this, we can supply the investigators with more information about the case.  Forensic scientists studying toxicology can analyze various types of samples that can be used while considering the context of a crime scene. Knowing the crime scene and what happened is half the battle when solving a crime. In this blog, we will analyze the various ways of samples can help solve crimes.

Types of Samples

            A forensic toxicologist is normally given preserved samples of body fluids, stomach contents, and organ parts with a report about the victims symptoms and or post-mortem data. There are more samples but this blog will be limited to just four samples.

• Urine

• Blood

• Hair

• Oral fluid

Urine can be analyzed for drug presence and is less likely to be infectious with diseases. Blood can confirm most common toxic substances that the victim was influenced by at the time. Hair can record medium to long term (up to a year) dosages of substance abuse. Oral fluid; saliva, contains concentrations of drugs used and is good for recent drug use analysis.

Information on Analysis

            To analyze any sample, the scientists use analytical chemistry techniques to detect and identify foreign chemicals in the body. Lee Lerner and Brenda Wilmoth state, "Toxins can be simple metal ions or more complex, inorganic and organic chemicals, as well as compounds derived from bacteria or fungi and animal-produced substances such as venoms" (1). The three categories that forensic toxicologists study are:

Identification of drugs such as heroin, cocaine, cannabis; detection of drugs and poisons in body fluids, tissues, and organs; and measuring of alcohol in blood or urine samples.   Results of the laboratory procedures must then be interpreted and are often used as           evidence in legal cases (Lerner and Wilmoth 1).

Forensic toxicologists begin analysis by screening tests, processing any sample for toxins. There are four different types of screening tests used. According to Lerner and Wilmoth:

Firstly, physical aspects of a substance such as boiling point, melting point, density, and refractive index can be determined. Secondly, the substance can be crystallized, which can give a wealth of structural information. Thirdly, chemical spot testing can be done.     Here, a substance is treated with a chemical reagent to produce crystals. Fourthly, thin     layer or gas chromatography can be used to separate individual chemical components of a mixture (1).

With the screening tests, the toxicologists can analyze the samples and conclude on whether the presence of drugs were found in the sample and or victim.

Examples of Toxins in Cases

According to Rafael Banon:

1.--Cases of mistreated children or elderly people:

The detection of urine stains on sheets, blankets or mattresses, together with determining the toxic substances present, could be of great usefulness. The same may be said of such detection on nappies, sanitary towels or other hygienic materials.

2.--In "drug facilitated sexual assault" (DFSA), following the discovery of the scene of   the crime, the detection of a drug in urine stains found could provide all-important     evidence of a crime. Traces could be found on surfaces such as sheets or vehicle seats, among others. Finding them on these surfaces is of great importance due to the short average lifespan of the toxic substances that are usually employed. [...]

5.--Finally, in other cases of sexual aggression with development of paraphilia behaviour--such as urophilia or undinism--the non-detection of toxic substances in the urine stains found on the victim, would be of great value. [...] This could also apply in other crimes such as robbery, burglary, etc. to stains found at the scene of the crime(1).

Conclusion

            In the forensic science of toxicology, the simple analysis of drug presence can mean the context of a crime scene or a criminal. Nowadays with education, criminals are increasing their intelligence and becoming more careful. Thus the need for every forensic science, as every small piece of evidence could mean the life of a case.

Works Cited

Banon, Rafael, et al. "A crossroad between criminalistics and forensic toxicology." The Internet Journal of Forensic Science 14 Dec. 2009. Science In Context. Web. 6 Mar. 2013.

"Toxicology." World of Forensic Science. Ed. K. Lee Lerner and Brenda Wilmoth Lerner. Detroit: Gale, 2006. Science In Context. Web. 6 Mar. 2013.