This document provides an overview of hair structure and forensic examination of hair evidence. It discusses the introduction, history, structure, growth and types of hair. It also covers the composition of hair, human races, collection and packaging of hair evidence. The document explains the forensic significance of hair for determining origin, sex, age and other characteristics. It describes microscopic examination techniques like temporary mounts, permanent mounts and cross-sectioning. The document concludes by discussing the differences between human and animal hair.

1. DR A.P.J KALAM INSTITUTE OF
FORENSIC SCIENCE AND
CRIMINOLOGY
TOPIC: HAIR
Ahsan Ali
M.Sc. 2nd Year

2. CONTENT
PRESENTATION
TITLE
2
• INTRODUCTION
• HISTORY
• HAIR STRUCTURE
• COMPOSITION OF HAIR
• GROWTH OF HAIR
• TYPES OF HAIR
• HUMAN RACE
• LOCATION, COLLECTION AND PACKAGING
• FORENSIC EXAMINATION OF HAIR
• DIFF. BETWEEN ANIMAL & HUMAN HAIR

3. INTRODUCTION
PRESENTATION
TITLE
3
• Study of hair is called “Trichology”.
• Hair is a protein filament that grows from
follicles found in the dermis, or skin.
• Hair an important biomaterial primarily
composed of protein, notably keratin.
• Hair is found as an evidence in various types of
crimes like murders, assaults, rapes, abortions etc.
• Hair can withstand the effect of the various
environmental conditions as compared to other
bodily tissues.

4. CONTD…..
• They are routinely examined and compared for morphological and
physical characters for determining the site, sex, race , species origin and
for individualization etc.
• The characters that are commonly used are color, breadth of hair and
medulla, scale count, medullary index, hair index, scale count index etc.
• In extremely rare cases, the presence of some individual dye,
contamination, some extraordinary defects or disease in the hair can
permit individualization.
4
PRESENTATION
TITLE

5. HISTORY
• 1897 – Rudolf
Virchow became
the first person to
do an in depth
study of hair.
• 1906 - Hugo Marx
wrote a paper on
the use of hair in
forensic
investigations to
determine identity.
5
PRESENTATION
TITLE
• 1931- Dr. Paul Kirk
worked on new ways to
improve the use of hair
in forensic
investigations.
• 1936-1973 : Smith,
Nickolls , Niyogi ,
Moenssons et al., King
et al.
examined hair roots
whether the hair has
fallen naturally or pulled
out forcibly.
Edmond Locard
(1920), noted for
his exchange
principle.

6. STRUCTURE OF HAIR
Hair shaft
Sebaceous
gland
Hair follicle
Blood
vessels
Sweat gland
Epidermi
s
Melanocyte
Dermis
Subcutaneous
fat
Papilla of hair

7. SOME DEFINITIONS
• Hair follicle: Tube like organ in under layer of dermis
and is linked to the body’s blood supply.
• Papilla: Indentation of hair follicle where blood
vessels, nerves enter and exit.
• Matrix: Area of cell division and hair growth.
• Root: Portion of hair below the skin, embedded in the
follicle.
• Shaft: Non-living and that can be seen above the skin
surface.
• Hair Bulb: Onion shaped portion of the lower hair
follicle including the hair matrix and follicular papilla .
• Sebaceous Gland: Secrets oil to help the hair
conditioned.
7
PRESENTATION
TITLE

8. PRESENTATION
TITLE
8
COMPOSITION OF HAIR
Keratinocytes( Keratin)
• Elemental
Composition
• Mineral
Composition
Melanocytes(Melanin)
• Eumelanin • Phenomelanin
 Carbon 45%
 Oxygen 28%
 Nitrogen 15%
 Hydrogen 6.7%
 Sulphur 5.3%
 Calcium
 Magnesium
 Potassium
 Iron
 Manganese
 Boron
 Copper
 Sodium
Etc.
 A dark
pigment,
usually
brown
and
black in
colour.
 A lighter
pigment,
usually
red and
yellow in
colour.

9. GROWTH OF
HAIR
ANAGEN (ACTIVE PHASE)
 2 to 6 years
 Growing phase of hair
 Producing new cells
CATAGEN(TRANSITIONAL PHASE)
 2 to 4 weeks
 Stops growing
 Detaching slowly
9
PRESENTATION
TITLE
TELOGEN (RESTING PHASE)
 3 to 5 months
 Follicle Rest
 Prepares next cycle

10. TYPES OF HAIR
1 0
PRESENTATION
TITLE
LANUGO
HAIR
VELLUS
HAIR
TERMINAL
HAIR
 very thin, soft usually
unpigmented hair that
covers the unborn or
newborn human
 the short, fine, “peach
fuzz” body hair that
grows in most places on
the human body in both
sexes. It covers most of
the body during
childhood
 longer, coarser, thicker and
darker fully developed
hairs. The conversion from
vellus to terminal is
stimulated by androgenic
hormones during puberty

11. HUMAN HAIR:
DIFFERENT SITES
 Scalp hair
 Pubic hair
 Vulvar hair
 Chest hair
 Beard hair
 Axilliary hair
1 1
PRESENTATION
TITLE
 Eyebrow hair
 Eyelash hair
 Nose hair
 Limb hair

12. HUMAN RACE
PRESENTATION
TITLE
1 2
MONGOLOID
Indian Hair
CAUCASOID
European Hair
NEGROID
African Hair
AUSTRALOID
Outdated historical grouping of
various people indigenous
to Melanesia and Australia

13. HAIR STRUCTURE –HAIR SHAFT
LAYERS OF THE HAIR:
1 3
PRESENTATION
TITLE
Cuticle
Cortex
Medulla

14. 1 4
PRESENTATION
TITLE
CUTICLE: It is a thin
translucent layer surrounding the
hair shaft.
The cuticular layer consists of
overlapping, non-nucleated,
pigment free cells which form
scales.
Coronal
Spinous
Imbricate

15. 1 5
PRESENTATION
TITLE
CORTEX
•Variable amount of
delicate air spaces
known as the cortical
fusi are interspersed
among the keratinized
cells of the cortex.
• The coloring
pigment granules
(melanin) are
interspersed
throughout the cortex.
•It is composed of
elongated, fusiform,
keratinized filaments
aligned in a regular array
parallel to the length of
the hair.
• These pigment granules
are evenly distributed or
concentrated more
towards the peripheral
region of cortex of human
hair.

16. PRESENTATION
TITLE
1 6
CONTINUOUS SOLID FRAGMENTED INTERRUPTED ABSENT
 It originates from the matrix cells at the apex of the dermal papilla.
 Large amount of glycogen is found in medullary cells.
 The medulla of hair varies widely among the different species and is one of the most valuable
morphological character available for species origin. In humans , the medulla is narrow , the
medullary index is 0.33 or less and in animals more than 0.33.
MEDULLA

17. LOCATION OF HAIR EVIDENCE
 Scene of occurrence.
 On the body and clothes of
victim.
 On the body and clothes of
suspect.
 On the weapon of offence.
 The vehicle.
 The routes.
 Miscellaneous articles.
1 7
PRESENTATION
TITLE

18. COLLECTION AND PRESERVATION
OF HAIR EVIDENCE
 COLLECTION SHOULD BE DONE BY
HAND. STICKY TAPE, TWEEZERS AND
LINT ROLLERS MAY ALSO BE USED .
 A SPECIAL FILTERED VACUUM
CLEANER MAY BE USED TO COLLECT
HAIR FROM CARPET, BEDDING, ETC.
 IF THE EVIDENCE IS STUCK TO
ANOTHER OBJECT , THE ENTIRE
OBJECT SHOULD BE PACKAGED AND
LABELED.
1 8
PRESENTATION
TITLE
Fig. Evidence Collecting
Vacuum
Fig. Evidence Collecting Lint
Roller

19. CONTD….
 ONCE COLLECTED, THE HAIR EVIDENCE SHOULD BE PACKAGED INTO PAPER
PACKETS OR IN PLASTIC BAGS.
 HAIR COLLECTED FROM DIFFERENT PLACES SHOULD BE KEPT IN SEPARATE
PACKETS OR BAGS.
 IF STICKY TAPE OR A LINT ROLLER ARE USED, THE ENTIRE SURFACE USE D
SHOULD BE PACKED INTO A POLYETHYLENE STORAGE BAG.
 CONTROL SAMPLES NEED TO BE COLLECTED FROM BOTH THE VICTIM AND TH E
SUSPECT.
 THE SITE OF ORIGIN OF THE HAIR SAMPLES COLLECTED FROM VARIOUS PA RTS
SHOULD BE SPECIFIED.
1 9
PRESENTATION
TITLE

20. FORENSIC
SIGNIFICANCE
OF HAIR
PRESENTATION
TITLE
2 0
1. Whether the material is hair or not?
2. Is the hair of human or animal origin?
3. What is the site of origin ?
4. To which sex it belongs?
5. What is the age of the individual to
whom the hair belongs?
6. Whether the hair was pulled out
forcibly or naturally?
7. To which race it belongs?
8. Is it possible to individualize hair or
not?

21. FORENSIC
EXAMINATION
OF HAIR
PHYSICAL TEST
MICROSCOPIC TEST
 Temporary Mount
 Scale casting
 Permanent Mount
 Cross Sectioning
 Micrometry: max diameter of medulla/ max diameter
of hair shaft
2 1
PRESENTATION
TITLE
CHEMICAL TEST
 DNA Test
 Neutron activation analysis: Metal detection
 Radio Immuno Assay Technique: drug detection
BURNING TEST
 If the Hair singes and burns
upwards while smelling like burnt
hair.
 Colour
 length
1. Whether the material is hair or not?

22. MICROSCOPIC
EXAMINATION
OF HAIR
TEMPORARY MOUNT
• Make a temporary mount of the hair sample on
a clean slide with the distilled Water or
glycerin.
• Cover with cover slip.
• Observe morphological characteristics under
microscope.
CELLULOSE ACETATE METHOD
• On a clean microscopic slide, place a thin layer
of cellulose acetate paste with low viscosity.
• With fine forceps, place hair on to the cellulose
acetate paste and press with another clean
slide. Allow it to dry for 2-5 min.
• Observe scales of hair under microscope.
2 2
PRESENTATION
TITLE
POLAROID COATER METHOD
• Place the hair on a clean microscope slide, securing the
ends with cellophane tape.
• Using a Polaroid film coater, make 2 or 3 passes along the
length of the hair.
• Allow the coating to dry for 23 hours.
• After removing the cellophane tape, gently peel the hair
from the slide.
• With a sharp scalpel, slice away the excess coating
protruding above the flat surface of the scale cast.
• Observe the scale impressions microscopically.

23. MICROSCOPIC
EXAMINATION
OF HAIR
PERMANENT MOUNT
• Place hair on slide in a drop of xylene and add
permanent mounting medium.
• Place a cover slip on the hair allowing the
medium.
• Label the slide appropriately and allow it to dry
for 48 hours.
CROSS SECTION METHOD
• Clean hair in solution of ether and ethanol in
ratio 1:1
• Bundle the samples and dip in a block of molten
wax and allow to cool.
• Cross sections can be taken either with a sharp
blade or with a microtone to a thickness of 5-10
microns.
• Place sections on a clean slide and dissolve wax
with a drop of xylene.
• Prepare permanent mount of the sections and
examine under the microscope.
2 3
PRESENTATION
TITLE
MICROMETRY
• Micrometry With the help of micrometer measure
following distances & calculate different indices:
• Maximum diameter of the shaft.
• Number of scales per unit length.
• Diameter of hair in microns / scale count.
• Maximum diameter of hair medulla / Maximum
diameter of hair shaft.
• Minimum diameter of shaft / Maximum diameter of the
shaft x 100

24. 2 4
PRESENTATION
TITLE
2. Is the hair of human or animal origin?
 On the basis of scales patterns of cuticle.
 On the basis of medullary ratio.
 On the basis of color and pigmentation.
3. What is the site of origin?
 Can be determined on the basis of structural analysis.
 Head Hair Pubic Hair Beard Hair etc.
4. To which sex it belongs?
 Can be determined by the presence of barr bodies.
5. What is the age of individual to whom the hair belongs?
 Through microscopic examination but not definitively.
FORENSIC
EXAMINATION
OF HAIR

25. 6. Whether the hair is pulled out forcibly or
naturally?
 By examining the root bulb.
7. To which race it belongs?
 I. Negroid
 II. Mongoloid
 III. Caucasian
8. Is it possible to individualize the hair or not?
 It is not possible to individualize the hair and say
that they belong to a particular person.
2 5
PRESENTATION
TITLE
FORENSIC
EXAMINATION
OF HAIR

26. DIFFERENCE BETWEEN HUMAN AND ANIMAL
HAIR
HUMAN HAIR
1) Human hair is the protein filaments grows from
the follicles of the skin dermis.
2) The medulla in human hair is thinner.
3) Medullary Index is 0.33 or less than 0.33.
4) Spinous scales are not present in human hair.
5) Coronal scale patterns are extremely rare in
human hairs.
6) Cuticle in human hair is Imbricated.
7) The root is commonly club-shaped in human
hairs.
8) Distribution of pigment is towards cuticle.
9) The width of cortex is grater than medulla.
10) General appearance of human hairs are fine and
thin.
ANIMAL HAIR
1) Animal hair is the protein filaments found on their
skin.
2) The medulla in animal hair is thicker.
3) Medullary Index is more than 0.33.
4) Spinous scale are found on the hair of cats, seals and
mink.
5) Coronal scale patterns are found on the hair of bats
and some other rodents.
6) Cuticle in animal hair is coronal or spinous.
7) The roots are highly variable between animals.
8) Distribution of pigment is towards central or towards
medulla.
9) Usually less than width of medulla.
10) General appearance of human hairs are thick and
course.
2 6
PRESENTATION
TITLE

27. REFERENCE
2 7
PRESENTATION
TITLE
 Anil Aggrawal: Forensic Medicine and Toxicology for MBBS,
First edition.
 Saferstein, R.(1982): Forensic Science Handbook, Vol.I, II,
III, Prentice Hall, New Jersey; Pg no.184-209.
 Sharma B.R.: Forensic Science in Criminal Investigation &
Trials,2003; Pg no.679-689.
 Robertson, J.(1996): Forensic Examination of Hair, Taylor
and Francis, USA. ; Pg no. 163- 186.
 Saferstein, Richard: Criminalistics: An Introduction to
Forensic Science. 9. Upper Saddle River, NJ: Pearson
Prentice Hall, 2007.
 Deedrick , Douglas: "Hairs, Fibers , Crime and Evidence."
Forensic Science Communications 2.3July 2000 16 003
2008
<http://www.fbi.gov/hq/lab/fsc/backissu/july2000/deed
ric1.htm>.
 Kathy, Steck -Flynn: "Trace Evidence: Hair." Crime and
Clues: The Art and Science of Criminal Investigation. 03 009
2006. 16 Mar 2008
<http://www.crimeandclues.com/hair_evidence.htm>.
 www.coolphysics.org/Hair,%20Fiber,%20and%20Paints%2
005.ppt

28. THANK YOU