Essay about Forensic Hair Analysis

1801 Words Nov 25th, 2013 8 Pages
Forensic Hair Analysis Forensic hair analysis is a method of studying hair found at the scene of a crime, and the scientific study of hair is referred to Trichology. In this paper I will discuss the different techniques that are used to study hair during an investigation and the many different aspects of the hair to consider based on what type of investigation is taking place. Hair analysis can be used to determine the presence of a suspect at the scene or to detect the presence of certain chemical substances in the victim or suspect. With the help of DNA techniques used in forensic hair analysis an absolute match can be determined by examining hair found at the scene of a crime. According to Douglas Deedrick of the FBI’s …show more content…
The shaft of the hair is comprised of three parts; the medulla, cortex, and cuticle. The medulla is the inner most part of the air and is surrounded by the cortex which makes up the majority of the hair. The final part is the cuticle which is the outermost part of the hair and is a single layer of scales. One technique used to distinguish the difference between human and animal hairs is to examine the scale patterns of the hair through a microscope. According to Vinayak “The scales of an animal’s hair show many distinctions such as coronal (crown-like) and spinuous patterns, whereas in the case of humans the scale patterns are of the ‘imbricate’ type (flattened) [2,3]. Besides, the medullary index, which is the ratio of the medulla’s width to the diameter of the hair, is 1/3 and below in humans compared to greater than 1/3 in animal hairs, due to the greater width of the medulla in animals”. (Vinayak, Chitralekha, S.Kaur, Kadyan, & A.Rai, 2012) Hair is classified on the human body by forensic scientists into six different types; head hair, eyebrow and eyelash hair, beard and moustache hair, body hair, pubic hair and axillary hair. According to Vinayak “Human hair undergoes cyclical phases of growth (anagen), transition (catagen), and resting (telogen). The average anagen phase lasts about 1,000 days and usually lasts for 100 days. At any time, between 10 and 18% of all the hairs on a human head are in the telogen phase; about 2%

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