1 / 37

Hair Examinations

Hair Examinations. Hair : - A long slender outgrowth from the follicles of mammals – composing three regions (cuticle, cortex and medulla). Its basic components are keratin (a protein) and melanin (a pigment). What is a hair?. View through the Microscope. Humans Covers the entire body

snow
Download Presentation

Hair Examinations

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Hair Examinations

  2. Hair : - A long slender outgrowth from the follicles of mammals – composing three regions (cuticle, cortex and medulla) Its basic components are keratin (a protein) and melanin (a pigment)

  3. What is a hair?

  4. View through the Microscope

  5. Humans Covers the entire body Except: Palms of hands, Soles of feet and Lips

  6. Cuticle – (Scales)

  7. Cortex – (Body of the hair)

  8. Medulla – (Central Canal)

  9. Hairs • Composed of Keratins • A stable form of evidence under many conditions • Serves to protect the body • Eyes- protects • Nose - filters • Head – thermal protection / physical protection • Growth – Anagen, Catagen, Telogen

  10. Microscopic Examination of Hairs Hair or Fiber? Animal Hair? or Human Hair?

  11. Species Identification of Animal Hairs Rabbit Seal Chinchilla Fox

  12. Identification of Animal Hairs • Scales • Color banding • Medulla morphology • Shaft Shape Cow Hair

  13. Identification of Animal Hairs • Scales

  14. Scale Casting • A negative cast of the scale pattern • Microscope slides • Clear glue-like material (Nail polish / hair spray) • Hair sample

  15. Seal Hair

  16. Scale Cast of a Seal Hair

  17. Various Scale Patterns

  18. Identification of Animal Hairs Color banding

  19. Medulla Morphology Identification of Animal Hairs

  20. Shaft Shape Identification of Animal Hairs

  21. Identification of Animal Hairs Root Shape Cat Root Dog Root

  22. Human Hairs Huam

  23. Human Hairs -Racial Origin Anthropological Determination Mongoloid Caucasian Negroid

  24. Body Area Identification of Human Hairs • Head • Pubic • Body Hair • Limb • Chest • Eye brow / lash • Facial • Underarm Head Pubic

  25. Means of Removal Forcibly Removed or Naturally Shed

  26. Fresh Cut

  27. Razor Cut

  28. Split Ends

  29. Ringed Hair

  30. Artifacts

  31. Damage Crushed Curler Damage

  32. Artificial Treatment

  33. Known Hair Sample Collection • Pulledfrom the donor – not cut • Placed in a sealed druggist fold and envelope • Represents entire area • At least 25 hairs • Collected as soon as possible

  34. Hair Examinations: Macroscopic – Screening 7x Microscopic- Identification 40x, 200x

  35. Hair Comparisons • Head and Pubic only • Not a means of positive Identification • Can exclude a donor • Comparison microscope • Compare similar areas to each other • Some hairs are not suitable to compare

  36. Masks Hats Caps Sweaters Blankets Stockings Vacuum Debris Combings Windshields Weapons Types of Evidence to Process

More Related