Forensic entomology is used to determine such crimes as murder, suicide, and other criminal acts by examining various insects instead of using human tissues. This forensic tool is used to determine the postmortem interval of a corpse and the cause of death of a corpse when all other forms of human evidence (human blood, tissues, hair, etc.) are not present at the scene. Forensic entomologists prefer using insects to determine these factors of death because the insects produce similar results as human test materials such as human blood or tissues which yield the best analytical results for the forensic entomologist. The use of forensic entomological evidence has been accepted and used in many courts around the world (Anderson, 1999). The use of this tool in court can support or refute a suspect’s alibi and improves the criminal investigation against the suspect (Anderson, 1999). Even though forensic entomology is an efficient tool to use in criminal investigations there are some drawbacks to this analytical tool. Such disadvantages include improper collection of entomological evidence and improper analysis of insects after collection, resulting in incorrect entomological results and a possible false conviction of a suspect. The proposed research of this paper focused on insects being affected by different concentrations of ethanol during natural insect development and also focused on the detection of ethanol in insects using gas chromatography mass spectrometry (GCMS) to determine if insects were significantly affected by ethanol exposure. The research also focused on the exposure of ethanol to the insects and how this exposure affected PMI (postmortem interval) determination. Forensic entomology is a commonly used tool to determine cause and time of death by examining various characteristics of insects that are collected at the crime scene. Such characteristics include size of the insect(s) and the life cycle stage of the insect collected. Forensic entomology becomes the most accurate and sometimes the only tool available for determining time of death, especially after 72 hours (Anderson and VanLaerhoven, 1996). Forensic entomology can also determine if a body has been moved from place to place, determine where the death occurred, determine the presence of various types of drugs and toxins present (if any), wound location, and determine who the suspect and victim are due to the presence of certain insects on the body (Grisales, et al., 2010). Background/Literature Review
There are five levels of decomposition identified by a forensic entomologist when conducting an entomological investigation which include fresh, bloated, active, advanced, and remains (Grisales, et al., 2010). These stages of decomposition are important to a forensic entomologist because insects appear on a corpse periodically throughout the decomposition cycle which therefore determines the time of death of a corpse. During these levels of decomposition insects begin to reach the corpse either by flying (adult flies) or by burrowing through the ground (pupae). Some insects can also reach the corpse by hatching from eggs (larvae) that were laid on the corpse after death. The fresh stage of decomposition involves a drop in body temperature and the appearance of very few flies on the corpse. The insects that are collected are typically larvae and are collected from the mouth of the corpse. The bloated stage of decomposition involves a significant increase in the body weight of a corpse due to rainfall exposure. The insects that are collected at this stage of decomposition are larvae found on the back, head, ears, and anus of the corpse (Grisales, et al., 2010). The active decay stage of decomposition involves fly larvae feeding on a corpse which significantly lowers the body weight of the corpse and an increased amount of fly larvae found in the intestines/ organs of the corpse (Grisales, et al., 2010). The advanced stage of decomposition...
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