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Long-Lasting
Lipsticks and Latent Prints
Ana Castello
Biochemist
Mercedes Alvarez
Assistant Professor of Legal Medicine
Marcos Miquel
Assistant Professor of Legal Medicine
Fernando Verdu
Professor of Legal Medicine
Department of Legal Medicine
College of Medicine and Odontology
University of Valencia
Valencia, Spain
Abstract.......Introduction.......Materials
and Methods.......Results
Conclusions.......References
Abstract
The investigation
of latent prints can be fundamental in resolving a criminal act.
In addition to fingerprints, lipstick smears can be investigated.
Traditional lipstick produces a print that is easily identifiable.
However, lip prints made with long-lasting lipstick can be invisible,
requiring reagents that are more sensitive than conventional materials
to locate and develop the prints. This study analyzes the effectiveness
of reagents that are generically called lysochromes (Sudan III,
Oil Red O, and Sudan black) in developing recent as well as older
latent lip prints on porous surfaces.
Introduction
The investigation
of latent prints can be fundamental in resolving a criminal act.
There are different physical and chemical methods that enable locating
and developing latent prints (Trozzi et al. 2001). It is also feasible
to extract DNA from the print (Fregeau et al. 2000; Zamir et al.
2000).
In addition
to fingerprints, lipstick prints can be of forensic interest. Lipstick
smears can lead to indirect proof of a relationship or contact between
a victim and a suspect or a suspect and a crime scene (Ehara and
Marumo 1998). Also, the possibility of extracting DNA from saliva
on a lipstick print may be valuable in an investigation.
Traditional
lipstick produces a print that is initially easily identifiable
(Lucus and Eijgelaar 1991; Russell and Welch 1984). However, the
cosmetics industry has developed long-lasting lipsticks that often
do not leave visible prints.
Different lipsticks
have different compositions. During the manufacture of long-lasting
lipstick, the oil content is reduced to a minimum. Thus, development
using conventional powders and reagents is more difficult. Previous
studies analyzed the effectiveness of several fingerprint powders
and reagents on lipstick prints. Of these, fingerprint red (Dragon's
Red), fingerprint black, and silver metallic powders were found
to be the most effective (Alvarez 1999; Seguí et al. 2000).
It was also determined that sublimated iodine does not produce development.
Thus, it is necessary to find other development methods that are
more sensitive to oils and more easily applied.
Lysochrome is
a generic term for compounds that have the ability to dye fatty
acids (Budavari 1996; Lillie 1969). Their molecule contains a portion
that dissolves in contact with fat (lyso) and another that is responsible
for color (chrome). Their use is common in histopathology for determining
fats in sections. One of these compounds, Sudan black, has been
used as a solvent in ethanol and water to develop latent fingerprints
described in the literature about surfaces contaminated with foodstuffs,
oils, and other fatty substances (Trozzi et al. 2001).
This study compares
the effectiveness of three different lysochromes (Sudan III, Oil
Red O, and Sudan black) to the fingerprint red (Dragon's Red), black,
and silver metallic powders as well as to ninhydrin in developing
latent lip prints from long-lasting lipsticks on porous paper and
cloth surfaces. The reagents were used both in powder and in solution
forms. Lysochromes have an advantage over a chemical reagent because
they react with fats and physical reagents.
Materials
and Methods
Materials:
Long-lasting lipstick
Unperfumed tissue paper
White cotton fabric
Bottles (dark storage, sprayer, plastic)
Brushes
Fume hood and fuming chamber
Glassware
Heater
Humidity chamber
Stirring device
Fingerprint
Powders:
Fingerprint
red powder (Dragon's Red)
Fingerprint black powder
Silver metallic powder
Reagents:
Ninhydrin
Acetone
Sudan III
Oil Red O
Sudan black
Ethanol
Distilled water
Methods:
Sample preparation:
After applying the lipstick on ten volunteers and waiting the recommended
five minutes for the lipstick to fix, lip impressions were made
on tissue paper and white cotton fabric using sustained pressure
for three seconds. The samples were exposed to ambient conditions.
Reagent preparation
(Trozzi et al. 2001):
Ninhydrin (acetone base) for 100 ml:
Ninhydrin
0.6 g
Acetone
100 ml
The reagent
was dissolved in acetone with minimal stirring.
Sudan III (solution)
for 150 ml:
Sudan III 1.5 g
Ethanol 100 ml
Distilled water 50 ml
The reagent was dissolved in ethanol, water was added, and the mixture
shaken.
Oil Red O (solution)
for 150 ml:
Oil Red O 1.5 g
Ethanol 100 ml
Distilled water 50 ml
The reagent was dissolved in ethanol, water was added, and the mixture
shaken.
Sudan black
(solution) for 150 ml:
Sudan black 0.375 g
Ethanol 100 ml
Distilled water 50 ml
The reagent was dissolved in ethanol, water was added, and the mixture
shaken.
Processing
procedure:
The latent lip prints were developed at intervals ranging from 1
to 40 days. Two observers independently performed the readouts of
the development. The protection measures recommended by the products'
Safety Data Sheets (Merck Schuchardt 1998) were followed. Some of
the development procedures are demonstrated in Figures 1, 2, 3,
and 4.
|
Figure
1
Photograph of a latent lip print on cotton fabric developed
using black powder after 30 days. Click
for enlarged image. |
|
Figure
2
Photograph of a latent lip print on cotton fabric developed
using Oil Red O (powder) after 30 days. Click
for enlarged image. |
|
Figure
3
Photograph of a latent lip print on cotton fabric developed
using Sudan black after 30 days. Click
for enlarged image. |
|
Figure
4
Photograph of a latent lip print on cotton fabric developed
using Oil Red O (solution) after 30 days. Click
for enlarged image.
|
Developing
with fingerprint powders (red, black, and silver metallic) and powder
lysochromes (Sudan III, Sudan black, and Oil Red O): Using a
brush, a small quantity of powder was carefully applied on the surface
where the attempt was being made to locate the latent lip print.
Enough of the background was developed to see the entire lip print.
Application continued and extended until the print could be seen
clearly. When using powder lysochromes, very little reagent was
used, but sufficient time was provided to allow it to work. With
time, the development became clearer, presenting a better quality
image.
Developing
with ninhydrin (acetone base): The reagent was applied to the
sample using a spray, then allowed to dry.
Developing with solution lysochromes: With the reagent in
a glass tray, the sample was submerged in the solution. When using
Sudan III or Oil Red O, the sample was left submerged for approximately
one minute, then removed. When using Sudan black, the sample was
removed immediately to prevent the paper or fabric from becoming
dyed. It was then rinsed with tap water and allowed to dry.
Results
The quality
of the development for the powders and reagents studied depends
on two factors: the surface type and the age of the latent lip print.
- On tissue
paper, neither recent nor older prints were developed using conventional
fingerprint powders (red, black, and silver metallic). On the
other hand, lysochromes (Sudan III, Oil Red O, and Sudan black)
applied as a powder and in solution produced high quality development
of prints up to 20 days old. The effectiveness of the development
diminished with the age of the print, with poor quality on older
prints.
- On white
cotton fabric, both conventional powders and reagents were used
to develop recent lipstick prints, but their effectiveness diminished
on older prints. Silver metallic powder achieved the best results
with high-quality development of prints up to 10 days old. Lysochromes
produced good quality development of prints up to 40 days old.
But on fabric as on paper, the effectiveness of the powder or
reagent diminished over time, and the quality of the development
was poorest on the oldest prints.
Analyzing the
results obtained for the two surfaces, the quality of lip print
development was better on fabric than on tissue paper, probably
due to differences in the structure of these surfaces. The tissue
paper's softer surface allows the development process to affect
the structure, producing poor results. Since it is more absorbent
than fabric, the print adheres to the tissue paper better, thereby
reducing the effectiveness of the powders and reagents. On the other
hand, the structure of woven fabric is more homogeneous, more uniform,
and firmer than that of paper. The components of the print do not
adhere well to the fiber; thus, the powders and reagents become
more effective. This explanation, however, is only hypothetical.
Tables 1 and
2 present the results of this study after developing latent lip
prints produced by long-lasting lipsticks using different fingerprint
powders and reagents after different dwell times. Table
1 shows the results on tissue paper; Table
2 shows the results on white cotton fabric.
The results
obtained for conventional powders and reagents were compared to
those derived from lysochromes, suggesting the following conclusions:
- Conventional
powders and reagents are less effective than lysochromes in developing
older lip prints. Moreover, results cannot be obtained on some
porous surfaces, such as paper.
- Lysochromes
applied either as a powder or in solution are effective on both
types of porous surfaces tested. They achieve development of recent
and older lip prints.
- Ninhydrin,
which reacts with amino acids in perspiration to make it an effective
reagent for developing latent fingerprints, provides no useful
results for lip prints, since there are no sweat glands in the
lips. The use of ninhydrin produced no reaction.
An analysis
of the results for the three lysochromes (Sudan III, Oil Red O,
and Sudan black) provided the following conclusions:
- Oil Red O
and Sudan black in powder form produced high-quality developments
for recent as well as older lip prints. Sudan III was less effective
for older lip prints than the other two reagents.
- Sudan III
and Oil Red O in solution produced good development (better with
the latter) of recent and older lip prints. The results were excellent
using Sudan black producing high-quality development of prints
up to 40 days old. However, this reagent may dye the paper or
fabric, preventing the print from being seen. To prevent this
dyeing, the concentration of the reagent in the solution should
be lowered, and the sample should be washed immediately after
application.
- Lysochromes
are effective in both powder and solution application forms. Of
the three reagents used, the best results were with Sudan black,
followed by Oil Red O and Sudan III.
Conclusions
This study shows
that lysochromes are very effective when used on long-lasting lipstick
prints on porous surfaces, such as paper or fabric, where detection
is usually difficult. Thus, lysochromes are a highly useful group
of compounds for locating and developing recent as well as older
latent lip prints.
References
Alvarez, M.
Cosmetic advances and criminalistics: The study of lip prints
generated by permanent lipstick. Doctoral thesis, University
of Valencia, Spain, 1999.
Budavari, S.
Merck Index, 12th ed., Elsevier, Rahway, New Jersey, 1996.
Ehara, Y. and
Marumo, Y. Identification of lipstick smears by fluorescence observation
and purge-and-trap gas chromatography, Forensic Science International
(1998) 96:1-10.
Fregeau, C.
J., Germain, O., and Fourney, R. M. Fingerprint enhancement revisited
and the effects of blood enhancement chemicals on subsequent Profiler
PlusTM fluorescent short tandem repeats DNA analysis
of fresh and aged blood fingerprints, Journal of Forensic Sciences
(2000) 45(2):354-380.
Lillie, R. D.
Conn's Biological Stains, 8th ed., Williams and Wilkins,
Baltimore, Maryland, 1969.
Lucus, D. M.
and Eijgelaar, G. An evaluation of a technique for the examination
of lipstick smears, Journal of Forensic Sciences (1991) 6:354-362.
Russell, L.
W. and Welch, A. E. Analysis of lipsticks, Forensic Science International
(1984) 25:105-116.
Segui, M. A.,
Feucht, M. M., Ponce, A. C., and Pascual, F. A. V. Persistent lipsticks
and their lip prints: New hidden evidence at the crime scene, Forensic
Science International (2000) 112:41-47.
Safety Data
Sheets. Merck Schuchardt, 1998.
Trozzi, T. A.,
Schwartz, R. L., and Hollars, M. L. Processing guide for developing
latent prints, Forensic Science Communications [Online].
(January 2001). Available: www.fbi.gov/hq/lab/fsc/backissu/jan2001/lpu.pdf
Zamir, A., Springer,
E., and Glattstein, B. Fingerprints and DNA: STR typing of DNA extracted
from adhesive tape after processing for fingerprints, Journal
of Forensic Sciences (2000) 45(3):687-688.
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