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Forensic Ultraviolet Lights in Clinical Practice: Evidence for the Evidence



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Forensic Ultraviolet Lights & Sexual Assault
Forensic Ultraviolet Lights in Clinical Practice:
Evidence for the Evidence
C. Carter-Snell*
Mount Royal College
Kathleen Soltys
Capital Health
*The authors would like to thank the members of the Sexual
Assault Response Team, the Birth Control Centre and Sgt.
Trevor Addison from Edmonton City Police Identification
Section for their assistance in conducting the initial pilot study,
and the members of the New Orleans SANE-SART conference
for their assistance with the replication. Comments concerning
this paper can be addressed to Cathy Carter-Snell, Department
of Nursing, Mount Royal College, Room Y331, 4825 Mount
Royal Gate SW, Calgary, Alberta, Canada, T3E 6K6 (email:
indy is an 18 year-old female who came to
Emergency for examination and treatment
following a sexual assault. Her treatment options were
reviewed and she chose to have a full physical examination, but
did not wish the police to be involved. She cited shame and
embarrassment, mainly because she had been quite intoxicated
at the time and had little recall of the event. She did recall the
male ejaculating on her thigh at one point and again on her
chest. During the examination it was noted that she had
fluorescence in both these areas, but they were not swabbed for
DNA analysis given her request that police not be involved. The
following day, Cindy reconsidered and reported to police about
the incident. Her case went forward to court based on the results
of the examination and the interviews. The sexual assault nurse
examiner was asked to testify about her findings, including the
stains she saw. A critical question, however, involves what the
examiner knows about the ability of the light to detect or rule out
certain stains, particularly semen. How confident could she be
regarding the type of stain she saw?
Unfortunately, the “evidence for the evidence” in
sexual assault practices has not always been established
beyond the laboratory. Ultraviolet lights and alternate
light sources have been used in forensic laboratories and
at crime scenes for years to look for blood and body fluid
stains. Recently, more portable versions of these lights
have been used with varying degrees of success in clinical
practice with victims of violence. Some forensic laboratory
scientists have expressed frustration with their use by
clinical staff, citing high rates of unnecessary swabs being
taken which turn out to be negative for semen or DNA, or
perhaps other fluids which are not of interest (e.g., hair
gel) when sent for analysis.
Clinically, some lights allow many substances to
fluoresce including hair gel, lubricant and other
innocuous substances, while other lights only make semen
and sometimes saliva fluoresce. In the clinical literature
there is confusion with terminology between ultraviolet
lights, Woods’ lamps and alternate light sources.
Furthermore, the descriptive literature is inconsistent
regarding what positive fluorescence looks like, ranging
Ultraviolet lights are used in clinical forensic practice,
particularly with sexual assault victims. Despite their
widespread use, there is little data on either the best
wavelengths of light for detecting semen stains, or on
the sensitivity and specificity of the wavelengths to
semen. In the descriptive literature there are varying
examples of the colour of stains under UV lights,
however this is not linked to particular wavelengths or
circumstances. Much of the related research has been
conducted on fabric samples rather than skin or with
different types of lights. In this article a review of the
literature on ultraviolet lights is provided, along with
the results from two preliminary studies.
Forensic Ultraviolet Lights & Sexual Assault
from greenish yellow or blue to white. There is very little
clinical literature as to the recommended wavelength of
lights for stains on skin, nor what the stain would look like
under various wavelengths. This information is vital in
order to educate practitioners appropriately. The purpose
of the present research is to attempt to clarify the use of
ultraviolet lights for sexual assault teams prior to
purchasing new lights. It is also hoped that the results will
inform and guide further understanding of what it is we
see when fluorescence is noted.
In order to understand the need for further research we
first describe fluorescence of stains and the role wavelengths
play in the ability to view fluorescence, including prior
research on the forensic identification of various stains.
Ultraviolet Wavelengths
In clinical practice we have come to call every ultraviolet
light either a “Wood’s Lamp” or an alternate light source
(ALS). These two terms describe very different wavelengths
of light and are not interchangeable. Ultraviolet (UV) light,
also known as ultraviolet radiation, is an energy emitted
in various wavelengths within the light spectrum. This
causes the substance being viewed to emit light, making it
appear fluorescent. UV lights may be short, medium or
long wavelengths (Royal Canadian Mounted Police, 2003).
The ranges of lights and their utility are shown in Table 1.
Table 1: Wavelengths of Light
Short wavelengths are seen in UVC radiation, which
emits wavelengths between 80 and 280 nanometres (nm).
Examples of sources of UVC include the sun and mercury
vapour lamps. The ozone layer around the earth generally
serves to protect us from UVC light. Unprotected skin and
eyes can sustain severe burns with prolonged exposure to
Term Wavelength (nm) Sources Comments
80-280 nm UVC radiation- sun,
mercury vapour lamps
Severe burns with
prolonged exposure,
corneal damage if <300 nm
280-320 nm
UVB radiation – sun, sun
lamps, early UV lights
Corneal damage possible at
lower end of spectrum,
burns if exposure >15 min
-also seen in earlier UV
lights (e.g. Woods)
Many substances fluoresce
besides semen/saliva
> 400 nm
Meant to refer to laser
light source but now
commonly to refer to UV
lights > 400 nm
Require goggles to filter
additional fluorescence
(yellow, orange or red
depending on stain, nm
level), more specific to
stains of interest
UVC sources. The cornea absorbs wavelengths of less than
300 nm so is susceptible to exposure. Medium wavelengths
are between 280 and 320 nm, and are considered UVB
radiation. Burns can be serious if skin or eyes are
unprotected. The sun emits UVB light as well as UVC. Other
sources include sun lamps, and some of the earlier UV
lights used in practice, such as the Mineralite.
Long wavelength ultraviolet light is known as UVA
radiation and is at least 320 nm to over 400 nm. This longer
wavelength, particularly over 400 nm, is the recommended
minimum for forensic use. The commonly used “Wood’s
lamp” typically had a wavelength of approximately 320 nm
whereas the newer lights in use are over 400 nm. There remain
some health and safety concerns related to the cornea and
lens of the eye with direct exposure, at least for lights with a
wavelength of closer to 300 nm VA light. Lights of up to 400
nm may cause injury with prolonged exposure such as more
than 15 min in an 8 hour period (Muller, Clydesdale, & Muller,
2001). Lights of 400 nm or over are less likely to cause damage.
Filters or goggles are required with 400 nm in order to more
easily view the fluorescence. At this level, the amount of
excitation causes bright light from surfaces surrounding the
stain to illuminate and this illumination light needs to be
blocked to reveal only the area actually fluorescing (Melles,
2002). High wavelengths are also more likely able to penetrate
the skin deep enough to reveal injuries under the surface
such as deep bruises not yet visible on the surface. The colour
of the goggle/filter varies by wavelength and what stain is of
interest. At the 450 nm level, if attempting to view semen, an
orange goggle is recommended (Sirchie, n.d.).
Another term often used in the literature is an “alternate
light source” or ALS. This term was originally used to
refer to argon ion laser lights, such as the Luma-lite. These
are more powerful lights that have a wider range of
visibility than ultraviolet lights. The use of laser instead of
ultraviolet radiation made it an “alternate source”.
Although technically incorrect, it has now become common
to use the term ALS to refer to any light over 400-450 nm.
Clinical experience with ultraviolet lights has shown that
we can detect various stains on skin. Depending on the
light, we may also be able to detect deep bruises before they
are visible on the skin. Some skin conditions such as subtle
forms of vitiligo (lightened skin patches) may also become
very evident with some lights.
This variability of light capabilities has lead to a
proliferation of types of lights. Vendors are attempting to
sell us “bruise lights” and “semen lights” and “saliva
lights” when in fact it is not the light per se but the
wavelength of light provided by the device. Unfortunately,
practitioners often do not know the wavelength of the light
they are using or the particular types of injuries or stains it
is capable of detecting.
It is recognized that many substances other than semen
can fluoresce. This is dependent upon the wavelength of
light and the properties of the substance. In the sexual
assault literature, new clinicians are advised that they may
recognize semen stains in ultraviolet light by their colour
when the stain fluoresces. Unfortunately, there is little
agreement in the sexual assault literature as to what to
expect. Semen stains are sometimes described as whitish
blue, as orange or as green. There is no mention of rationale
for the variation in colour such as the wavelength or type
of light used, which is likely to affect colour.
Detection of Stains
When body fluid stains are on surfaces such as skin or
fabric they may not be visible to the naked eye. The use of
fluorescent techniques such as ultraviolet lights and laser
lights allows us to see stains not otherwise seen. Use of
these lights to fluoresce fingerprints has been described as
significantly more sensitive than even using older staining
techniques (Dalrymple, 2001). When the ultraviolet light
or alternate light source is directed at an area, the light
from the substance/fluid is absorbed and another two types
of light are produced, making the area fluoresce. These
two new lights are known as excitation light and emission
light. In medium to long ultraviolet wavelengths (e.g., 320
nm with a Woods lamp), the excitation light is not visible
to the naked eye, and only the emission light is seen, making
the stain visible (Marshall, Bennett & Fraval, 2001). When
the excitation and emission light are both seen, it is difficult
to differentiate the stain from surrounding tissue which
also shows excitation light. This occurs at very long
wavelengths, in greater than 400 nm seen with alternate
light sources. When both lights are visible it is known as
the visible fluorescence spectrum. The only way to view
the stain is by blocking out the excitation light within that
fluorescent region. Barrier filters in the form of goggles or
camera filters are used for this reason. The colour of the
barrier filter differs with the range of light and the body
fluid to be seen. As an example, if looking for semen using
a 450 nm ultraviolet light, orange goggles are needed to
filter out everything but the emission light from the stain
and make the stain visible (Sirchie, n.d.).
The first report of UV lights being used to identify
semen was in 1919 by Dr. Wood, then subsequently by Dr.
Ito in 1927 (Marshall et al., 2001; Santucci & Nelson, 1999).
Most of the work involving UV lights has been conducted
on stains found on fabric, either at the crime scene or in the
laboratory. In sexual assault cases, the presence of semen
is particularly important to be able to detect. One of the
earlier studies involved comparison of a Mineralite (254
nm) with an argon laser light to detect saliva, semen and
sweat stains on fabric in different dilutions (Auvdel, 1987).
It was concluded that the Mineralite was able to detect
each of the stains and was found to be less expensive when
compared to laser.
In contrast, results from a subsequent study on a
Wood’s lamp with a wavelength of 320-400 nm were
disappointing. The Wood’s lamp was used in an attempt
to detect a wide variety of substances on fabric, including
semen and ointment (Santucci & Nelson, 1999). None of
the 29 semen samples, wet or dried, became fluorescent
under the Woods Lamp, resulting in limited detection
(sensitivity) and specificity to stains. This would mean
that many stains may be missed, and when a stain is
present it may not necessarily be semen, resulting in a high
number of false positive swabs being forwarded by the
clinician to the forensic laboratory. Their findings were
supported by earlier work on detection of dried semen
samples, in which it was recommended that semen required
a wavelength at least in the 350-450 nm range in order to
be visible (Stoilovic, 1991).
Subsequent research using higher wavelengths was
more successful in detecting semen. A Sirchie Bluemaxx
BM 500 with a wavelength of 450 nm was used by a group
of physician volunteers to identify semen stains (Nelson &
Santucci, 2002). The physicians were able to detect the
semen stains 100% of the time with the higher wavelength,
and 83% of the time they could be differentiated from other
stains after training. Unfortunately, it was difficult to find
studies which incorporated comparisons of wavelengths
in the same study for their utility in detecting various stains.
As noted, most of the research available has involved
stains on fabric. There is a limited amount of research
available regarding detection of stains on human skin.
When an ultraviolet light was used on 17 victims of assault
in another study, six patients showed fluorescence
(Lynnerup, Hjalgrim, & Eriksen, 1995). Four of these areas
were from lesions not normally seen in ordinary light and
two were saliva and semen. While limited in number, these
findings provide some indication of the value of UV lights
in clinical use. Another small study was conducted in
which 11 adult females had dried semen as well as urine
placed on their arms (Gabby, Winkleby, Boyce, Fisher,
Lancaster & Sensabaugh, 1992). The stains were sampled
with three tests: acid phosphatase, and 2 types of prostatic
protein30 tests. The stains were also examined with the
Wood’s lamp (254 nm). They found that the Wood’s lamp
was generally not sensitive to the semen, especially after
28 hours or more, and suggested that caution be exercised
in the use of these lights.
Detection of Injuries
Some limited work is also available in which the lights
have been used to detect various types of injuries. In a
Forensic Ultraviolet Lights & Sexual Assault
study of photographing of injuries, it was found that old
injuries visible at 450 nm with fluorescence photography
(Barsley, West, & Fair, 1990). Skin trauma and deep bruises
were noted in addition to stains in the study by Lynnerup’s
team (1995). Bitemarks, not yet visible on the surface, were
also described as visible when using 450 nm ultraviolet
lights (Golden, 1994). The lights have also been helpful in
detecting distinctive details of tattoos not seen with
ambient light on post-mortem subjects (Bennett & Rockhold,
1999). The ability to detect deep bruising is helpful in the
early stages. These marks may take 12-24 hours to appear
on the surface on living victims and may not appear post-
mortem. By the next day, the living victim has usually
returned home and evidence is lost which may support
their history of assault if they do not choose to return for
It may be seen from the above that a number of
questions remain unanswered in the ultraviolet light
literature. While it appears that higher wavelengths of
ultraviolet radiation are better for detecting semen, many
of the studies have been conducted on fabric rather than
skin. Furthermore, sufficient data is unavailable regarding
the sensitivity and specificity of certain wavelengths of
light for detecting semen. There is also relatively little
comparative data in which the sensitivity and specificity
of lights is compared across different types of substances
that may be found on a sexual assault victim’s skin. These
questions led us to conduct two preliminary studies on the
identification of semen.
Prior to purchasing new lights for the sexual assault
team, it was decided to conduct a small pilot study. The
purpose of the study was to compare three different
wavelengths of ultraviolet lights in terms of their ability to
detect the presence of semen (sensitivity) and their ability
to correctly conclude that semen was absent from a sample
(specificity). While the ability of the lights to note other
substances is of interest, it is the presence of semen, which
is of utmost interest for sexual assault victims.
Pilot Study
In order to answer the above questions, we obtained
four lights with different types of wavelengths. These are
shown in Figures 1and 2, and included: the Mineralite
(254 nm); the Evident (365 nm); and two different versions
of the Sirchie Bluemaxx lights, each at 450 nm. The
Bluemaxx BM500 was previously studied by Nelson and
Santucci (2002), but as seen in the photo, it is somewhat
large and cumbersome for a team that travels frequently. It
is like a very large, heavy flashlight (large enough to hold
3 “D” cell batteries) and several staff commented that their
To begin with, we applied saliva, semen and urine to
one researcher’s forearm. We showed volunteers how
these different fluids would look under each of the four
lights. We then applied a sample of each of the following
substances to numbered locations on the inner aspect of
the forearms of the other researcher: lotion; saliva; semen
(2 sites); condom lubricant; hair gel; talc powder; urine;
Muko (water soluble lubricant); Polysporin antibiotic
ointment; and liquid soap. A blank spot was also left in
one of the numbered sites as a control. Each substance was
Figure 2: Long and Alternate Light Sources
*Note: From top to bottom: Bluemaxx BM500 (450 nm),
Bluemaxx Mini (450 nm), Evident CE (365 nm).
Figure 1: Short Wavelength Light - Mineralite (254 nm)
wrists fatigued when using it for more than a few minutes
of holding it over a stain. The Bluemaxx Mini was more
like a mini-flashlight (7 inches long, 1 inch wide) and
therefore lighter to hold and carry.
placed within a numbered box drawn on the arm with
fluorescent marker. All liquids and gels were applied using
0.1 ml from a tuberculin syringe. The powder and condom
lubricant were smeared to fill the assigned observation
area, covering approximately the same size surface area as
the 0.1 ml fluid.
Five sexual assault nurse examiners (SANE’s), one non-
SANE RN and a student RN were asked to use each of the
lights to view the substances within 1 hour after applying
the substances. A police identification officer then
photographed each of the stains using time exposure
techniques and using an orange filter for the 450 nm lights
(similar to using the goggles to reduce extraneous light).
The results of the sensitivity and specificity for semen with
each of the lights are shown in Table 2. The sensitivity of
the lights to the other samples is shown in Table 3. It
should be noted that the Mineralite was sensitive to most
samples, and the Evident CE was sensitive to almost half
of them. In comparison, both the Bluemaxx lights were
positive for fluorescence with fewer fluids. The Bluemaxx
mini, with the exception of 1 rater who saw the polysporin
stain as positive, only fluoresced for semen. This would
make it the most specific to semen of all the lights.
Replication of Pilot
Based on the results of the pilot study, ethical approval
was received from the Health Region to replicate the study
on a larger scale at a conference for sexual assault examiners
and response teams in the United States during May of
2003. It was anticipated that we would be able to involve
at least 100 sexual assault examiners to participate at this
large international symposium. The study stains were
replicated using the same substances as the pilot. As before,
two of these stains were semen and one was a blank spot
for control purposes. Study participants were asked to view
the stains with all three lights representing 3 different
wavelengths (the Mineralite, the Evident CE and the
Bluemaxx Mini). They were asked to rate any stain they
saw by location, speculate whether it was positive or
negative for semen, and to note the colour of the stain.
We had a few challenges in implementing the study due
to difficulties in transporting and storing the semen sample
during travel, affecting the quality of the sample. Even
immediately after application it was difficult (although
possible) for the researchers to see one of the two semen
stains but the second was not visible at all with any of the
lights. There were further delays between stain application
and viewing of greater than 4 hours compared to less than 1
hour in the pilot. The final complication was related to
participation and location of the study room. The room was
difficult to find and the study was scheduled at the end of
the day, perhaps accounting for only obtaining 27
participants from the potential 280 attendees. This included
18 sexual assault nurses, 4 patient advocates, 3 police, 1
police officer, and 1 person of unknown occupation.
The final results of the sensitivity and specificity to
semen are shown in Table 4 for the one semen stain visible
to researchers. It may be noted that the Mineralite picked
up the semen most consistently, although it also gave a
very high false positive rate. In contrast, although the semen
stain was missed more often with the Bluemaxx Mini, there
was a higher rate of specificity. These findings need to be
interpreted cautiously in light of the study complications
noted above. A positive finding was that, despite the small
samples, the advocates and police were also able to detect
the one visible semen stain despite having had no prior
training with these lights.
Table 3: Sensitivity of Lights to Different Stains (%)
*Note: N = 7; 14% represents 1 rater who considered the
area “positive”, most often the same rater (a junior nurse
with no SANE experience and limited clinical
Lotion Saliva Condom
Powder Urine Muko Poly-
Soap Blank
(254 nm)
29 100 14 100 43 71 57 86 57 14
Products CE
(365 nm)
0 100 0 100 0 0 29 71 43 0
Bluemaxx BM
500 (450 nm)
0 14 0 14 29 14 14 0 0 14
(450 nm)
0 0 0 0 0 0 0 14 0 0
Table 2: Pilot Study Results (N=7)
Light Sensitivity Specificity Colour
(254 nm)
92.9 47.1 Blue
Evident Products CE
(365 nm)
78.6 57.1 Blue, blue-white,
light green
Sirchie Bluemaxx BM 500
(450 nm)
86.7 90 White, yellow-
white, green
Sirchie Bluemaxx Mini
(450 nm)
100 98.5 White, yellow-
white, light green
Table 4: Replication Study Results (N=27)
Light Sensitivity Specificity Colour
(254 nm)
85% 81% White (6), yellow (3),
green (2), blue (1)
Evident Products CE
(365 nm)
4 11 Green (1), blue (1)
Sirchie Bluemaxx Mini
(450 nm)
60 95 White (3), Orange
(1), yellow (1)
Forensic Ultraviolet Lights & Sexual Assault
It was seen in both studies that many of the substances
other than semen were fluorescent using the lights with
wavelengths below 450 nm. In contrast, the 450 nm lights
almost exclusively only fluoresced when the stain was
semen. Interestingly the smaller light was seen to be more
discriminate (i.e., greater sensitivity and specificity). In
the second study the comments from participants were
initially quite negative toward the 450 nm lights. They
expressed dislike at not seeing very many stains with the
longer wavelength lights, making comments such as, “but
it doesn’t show much”. These comments indicate the need
for education of staff used to medium or short wavelengths
of light who switch to longer wavelengths. Specifically, if
the intent is to be more confident that what one see is a
particular substance (e.g., semen or saliva), then one would
want it to show fewer non-relevant stains and be more
selective. There is no clinical benefit to seeing fluorescent
stains, which were not important to the case such as hair
gel. The inclination is to swab these stains if not sure of
their origin and this places an unnecessary burden on
forensic laboratories. We can also see that the colour of the
stains varied, although with some consistency. The more
bluish or white-blue stains were seen with lower
wavelengths while the white or white-green was seen with
the higher wavelengths. This is consistent with the
spectrum of light emitted by the higher wavelengths.
There were a number of limitations with this research.
First, the sample size of both studies was small. The only
benefit with the first study was the use of photographs,
which provided a permanent record of what was seen by
participants and have been validated informally by many
clinicians subsequent to the study. The attempt to replicate
in a follow-up study was fraught with challenges, most
notably the storage of the semen sample. Unfortunately both
the semen stains were difficult to see, especially one of the
stains, perhaps due to the storage issues, the location on the
arm (the one not visible was near the bend of the elbow), and
the longer period of before the stain was viewed.
We have seen that there are limited data for clinical
versus laboratory applications of ultraviolet lights. It is
important that we know what we are likely to be detecting
when fluorescence is noted, and that we can properly
incorporate this knowledge into training of new sexual
assault examiners and clinicians. Further questions also
emerge from these studies and from clinical practice.
Examples include the effects of different coloured skin on
visibility of semen stains, the point at which semen becomes
visible or stops being visible, the characteristics of deep
bruises or skin markings that may determine its visibility,
the recommended distance between skin and light source
for maximum visibility of stains, or the impact of stains
present on different body parts such as those covered by
clothing or areas washed frequently. Work on inter-rater
reliability would also be desirable.
It is recognized that these two studies are preliminary
in nature and require further replication. Plans are
currently in progress for a third study to answer some of
these questions. We had hoped with this preliminary work
to add to the body of “evidence for the evidence” as it relates
to ultraviolet light use. In Cindy’s case, we can still not be
certain of the origin of the stain. We need more research on
the sensitivity and specificity of various long wavelength
lights on various skin types and at various timeframes
after application of stains. We noted the difficulty in
viewing stains in the second study, which was longer post-
application. It would be important to look at the role of
time and normal “wear and tear” on stains since many
sexual assault victims come in at least 12-24 hours post-
assault. Stains could be altered with clothing rubbing on
them or with showering or attempts at hygiene. Ultimately
it is hoped through this work, further replication and related
studies that forensic clinical examiners will have a greater
degree of confidence in their interpretation of their findings
with the ultraviolet light. It is also hoped that such research
would lead to better discrimination of samples prior to
being sent to forensic laboratories for testing.
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techniques used in the detection of body secretions. Jour-
nal of Forensic Sciences, 32(2), 326-345.
Barsley, R. E., West, M. H., & Fair, J. A. (1990). Forensic
photography: Ultraviolet imaging of wounds on skin.
American Journal of Forensic Medical Pathology, 11(4), 300-
Bennett, J. L., & Rockhold, L. A. (1999). Use of an alternate
light source for tattoo recognition in the extended post-
mortem interval. Journal of Forensic Sciences, 44(1), 182-
Dalrymple, B. (2001). Serendipitous sleuthing. Canadian
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Gabby, T., Winkleby, M. A., Boyce, W. T., Fisher, D. L.,
Lancaster, A., & Sensabaugh, G. F. (1992). Sexual abuse
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Golden, G. S. (1994). Use of alternative light source illumi-
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the Law, 35(2), 165-168.
Marshall, S., Bennett, A., & Fraval, H. (2001). Locating se-
men on skin using live fluorescence. Web site:
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tutorial. Web site: URL
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violet light induced injury: Immunological and inflam-
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Nelson, D. G., & Santucci, K. A. (2002). An alternate light
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CATHY CARTER-SNELL received her Master of Nursing
from University of Alberta and is currently studying for her
PhD in Nursing. She is the Coordinator of Forensic Studies and
Emergency Nursing programs at Mount Royal College, Calgary,
as well as the nurse specialist for the Sexual Assault Response
Team (SART) in Edmonton.
KATHLEEN SOLTYS received her Masters in Health Studies
from Athabasca University. She currently works for Capital
Health, Primary Care Division as the manager of Birth control
Centre and the Sexual
... Within the UV spectrum there are various subgroups of which UV-A (320-400 nm) has the longest wavelength. Lights such as Wood's lamp with a peak output at about 365 nm are primarily used in medicine [1,2,16,22,23,25]. Common uses are to detect bacterial or fungal infections or to identify the presence of semen, saliva, blood, or urine by fluorescence [1,23]. ...
... To date, there has been no widely accepted age-classification system for hematomas, mainly because the initial energy and mechanism leading to it cannot be anticipated. Most hematomas appear within 12-24 h and, as rule of thumb, disappear within 2-3 weeks [2,17]. Visual analysis of hematomas is observer dependent and unspecific [14,15]. ...
... Alternative noninvasive methods such as colorimetry or reflectance spectrophotometry are dependent on multiple variables (e.g., skin color, hematoma size, body mass index). Although they show potential for aiding in hematoma identification, their additional value seems to be relevant only in the first 2 weeks after injury [2,7,8,18,21]. ...
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Background. To obtain forensic evidence of blunt trauma injury, physical examination (PE) is necessary but is only valid when an in- jury is visible. Identification of previously in- visible injuries through the application of ul- traviolet (UV) radiation is a phenomenon that has been known for decades, but to date has only drawn little attention in German legal medicine. Objectives. Toanalyzeatwhatpointintime UV examination (UVE) can be used as an additional noninvasive tool to identify potential blunt trauma injuries, especially when visual signs are absent. Materials and methods. Retrospective anal- ysis of reports from 28 individuals who underwent forensic examination for blunt trau- ma injury, including the use of UV-induced fluorescence. Results. In all, 28 subjects presented with 294 claimed injuries of which 205 were forensically verified to correspond with the mech- anism of injury. Injuries were visible longer with an increasing intensity of violence. UVE identified 62 % of these potential injuries in a time span of up to 31 weeks after blunt trauma, whereas PE alone identified only 19 %. Conclusion. UVE seems to be an essential aid for blunt trauma identification from the first moment of injury and is superior to us- ing PE alone. Therefore, UVE should be used as an additional tool with every PE, especially if the suspected injuries are older than 1 week, to obtain complete evidence of blunt trauma injuries.
... Another topic linked to multispectral photography is the detection and visualization of bodily fluids. Some studies have investigated the potential of different wavelengths to allow bodily fluids to be distinguished from other substances, such as liquids, gels and ointments [48][49][50]. Furthermore, studies and case reports have described the usefulness of different wavelengths to visualize latent bodily fluids on textiles [48,49,51] and human skin [48,50,[52][53][54]. ...
... Some studies have investigated the potential of different wavelengths to allow bodily fluids to be distinguished from other substances, such as liquids, gels and ointments [48][49][50]. Furthermore, studies and case reports have described the usefulness of different wavelengths to visualize latent bodily fluids on textiles [48,49,51] and human skin [48,50,[52][53][54]. UV fluorescence has been applied to detect cryptic skin particles on various materials [55]. ...
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Multispectral photography offers a wide range of applications for forensic investigations. It is commonly used to detect latent evidence and to enhance the visibility of findings. Additionally, three-dimensional (3D) full-body documentation has become much easier and more affordable in recent years. However, the benefits of performing 3D imaging beyond the visible (VIS) spectrum are not well known, and the technique has not been widely used in forensic medical investigations. A multicamera setup was used to employ multispectral photogrammetry between 365 and 960 nm in postmortem investigations. The multicamera setup included four modified digital cameras, ultraviolet (UV) and near-infrared (NIR) light sources and supplemental lens filters. Full-body documentation was performed in conjunction with the use of a medical X-ray computed tomography (CT) scanner to automate the imaging procedure. Textured 3D models based on multispectral datasets from four example cases were reconstructed successfully. The level of detail and overall quality of the 3D reconstructions varied depending on the spectral range of the image data. Generally, the NIR datasets showed enhanced visibility of vein patterns and specific injuries, whereas the UV-induced datasets highlighted foreign substances on the skin. Three-dimensional multispectral full-body imaging enables the detection of latent evidence that is invisible to the naked eye and allows visualization, documentation and analysis of evidence beyond the VIS spectrum.
... Participants first examine the face and mouth and practice with swabs and smear stains. A Wood's lamp, or an alternative light source, is a device that emits an ultraviolet light, and when flashed on certain substance or stains, will emit a flow or fluoresced appearance (Carter-Snell & Soltys, 2005). Substances such as saliva, urine, and semen are among some of the substances that will fluoresce and can indicate an area on a patient that should be swabbed for evidence collection (Carter-Snell & Soltys, 2005). ...
... A Wood's lamp, or an alternative light source, is a device that emits an ultraviolet light, and when flashed on certain substance or stains, will emit a flow or fluoresced appearance (Carter-Snell & Soltys, 2005). Substances such as saliva, urine, and semen are among some of the substances that will fluoresce and can indicate an area on a patient that should be swabbed for evidence collection (Carter-Snell & Soltys, 2005). Participants inspect the mouth and face for any dried secretions using a Wood's lamp. ...
Patients who have been sexually assaulted disproportionately experience gaps in healthcare delivery. Ensuring that healthcare providers who care for this population are adequately prepared is one way of addressing this gap. At the Brigham and Women's Hospital, a 4-hour long interprofessional Sexual Assault Simulation Course for Healthcare Providers (SASH) was developed and conducted at the hospital's Simulation, Training, Research, & Technology Utilization System Center. The SASH is offered using a variety of teaching methodologies including didactics, skill stations comprising how to collect forensic evidence, simulation experience with standardized patient, and debriefing. Using simulation as an educational method allows healthcare professionals to gain hands-on skills in a safe environment. Ultimately, the goal of the SASH is to enhance collaborative practice between healthcare professionals and to improve knowledge, with the purpose of improving care for patients who have been sexually assaulted.
... 1,4 As asserted by Snell et al., the effect of time on the detection of the stain must also be analysed, since most victims of sexual assault do not report the crime for at least 12-24 hours. 21 In this study, we aimed to reveal the effect of the time from staining to laundering on the detectability and identification of seminal stains on laundered clothes. To the best of our knowledge, this is the first investigation of these effects. ...
In some cases of sexual assault that are not reported to judicial authorities within a certain time, it is important to detect and identify seminal stains on laundered fabrics. In this study, we aimed to reveal the effect of the time from staining to laundering on the detectability and identification of seminal stains on laundered clothes. A total of 180 pieces of fabric (four different colours and five different types) were stained with seminal fluids, and three different lag times (12 hours, 1 week and 1 month) from staining to laundering were used. Three different laundering protocols were applied to these fabrics after staining. The built-in camera of the Mobile Multispectral UV-VIS-IR Imaging System® was used to take photos (1260 in total) of the stains with seven different wavelength and filter options, and the obtained images were evaluated. The Seratec® PSA Semiquant test was used to analyse the presence of prostate-specific antigen (PSA) in the seminal stains laundered after different lag times. We observed that in examining with the forensic light source (FLS) system, the time from staining to laundering affected the detectability of seminal stains on pieces of cloth. The best fluorescence was obtained in the examination of semen-stained fabric with FLS, particularly when the fabric was not laundered for one month after staining. On the other hand, the time from staining to laundering had a more limited effect on PSA test positivity than on the results of the examination with FLS.
... For the analysis of paintings even spectrally resolved imaging is used to identify materials in the artwork [3]. The police uses the UVF method to identify otherwise invisible traces at a crime scene [4]. For photovoltaic (PV) application, Pern reported in 1996 for the first time the application of UVF to analyze the degradation of the encapsulant (yellowing effect) in PV modules [5]. ...
Since 2010, the ultraviolet fluorescence (UVF) method is used to identify defects in wafer-based crystalline silicon photovoltaic (PV) modules. We summarize all known applications of fluorescence imaging methods on PV modules to identify defects and characteristics. The aim of this review is to present the basic principles for the interpretation of UVF images. The method allows for detection of cell cracks in a chronological order of occurrence, visualizing hot parts in a PV module, and identifying deviating bill of materials of PV modules. The effects of various material combinations on the UVF are reproduced in the lab and explained for the first time. Seasonal effects on the UVF are presented for the first time. In addition, some not yet understood features in the images are shown and discussed. Furthermore, the application of UVF imaging for manual, hood-based, and drone-based inspection is presented. The analysis speed of the three methods has been measured under real conditions. For the manual inspection, we found an evaluation speed of 250 modules/h, for a hood-based system 200 modules/h and the drone-based method allows an imaging speed of up to 720 modules/h.
... ALSs are widely utilized for examinations of individuals who present with concerns for sexual assault/sexual abuse in forensic medical and law enforcement settings. ALSs will identify areas of fluorescence (e.g., on skin, clothing, linens, etc.), which may be potential body fluid substances (i.e., blood, semen, saliva) (1)(2)(3)(4)(5) and allow for swabbing of those areas to acquire specimens. To determine whether the fluorescing substance (or area) is in fact body fluid with evidentiary significance, chemical, or serologic analysis of the specimen is a routine component of this process (6,7). ...
This single-blinded, randomized validation study was conducted to evaluate whether fluorescence under alternate light sources (ALS) is sufficient to diagnose subclinical bruising (bruising not visible under white light). Standardized trauma was induced on randomly selected ventral forearms. On days 1, 7, and 14 investigators independently examined case forearms under white light for perceived bruising and under ALS for fluorescence and compared body maps. 56 case and 62 control forearms (n = 118) were examined. Sensitivity of ALS on days 1, 7, and 14 was 76.8%, 69.6%, and 60.7%, respectively, compared to 69.6%, 60.0%, and 32.1% for white light. The specificity of ALS on days 1, 7, and 14 was 51.6%, 59.7%, and 53.2%, respectively, compared to 71.0%, 81.4%, and 86.9% for white light. ALS has increased sensitivity yet low specificity compared to white light in accurately detecting bruises. Fluorescence under ALS is not sufficient to accurately or responsibly diagnose subclinical bruising. © 2015 American Academy of Forensic Sciences.
Conference Paper
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- INTRODUCTION - In the last few years, postmortem 3D body documentation, especially through the use of photogrammetry, has gained importance in the field of forensic medicine. For this purpose, conventional digital cameras are used to capture information within the visible part of the electromagnetic spectrum (i.e., visible light). Moreover, the use of multispectral photography allows the detection and documentation of traces and injuries, for instance, in the ultraviolet (UV) or near-infrared (NIR) range, which are otherwise invisible to the human eye. Although multispectral photography offers a wide range of applications for legal investigations, multispectral photogrammetry is not yet well known or widely used within the field of forensic medicine. Therefore, within this study and the framework of the VirtoScan project, a method for multispectral whole-body photogrammetry was developed and evaluated. - MATERIALS AND METHODS - A multicamera setup based on four modified digital single-lens reflex cameras, different light sources, and additional lens filters was mounted on a mobile wooden frame. The setup was used in combination with a medical X-ray computed tomography (CT) scanner. Automatic table movement from the CT scanner was used to capture consecutive image sets of the body from head to toe. In addition to standard photogrammetry within the visible range, multispectral photogrammetry was performed under UV and NIR light sources at 365 nm, 400 nm, 860 nm and 960 nm on undressed human bodies and under blue light and NIR light sources at 450 nm and 860 nm on dressed mannequins. After the multispectral photogrammetry procedure was finished, a whole-body CT scan was conducted to capture the internal information of the human body. - RESULTS - Multiview 3D reconstructions based on multispectral image data from four forensic cases and four different sets of dressed mannequins were carried out successfully. The overall quality and level of detail of the polygon models from the undressed bodies varied with regard to the spectral range of the image data. Dressed bodies captured under blue and visible light exhibited reduced quality and reduced level of detail on the polygon models within areas of dark-colored clothing. Whole-body photogrammetry for undressed bodies took approximately 5 min under UV illumination and approximately 3 min under visible light or NIR illumination. Whole-body photogrammetry for dressed bodies took approximately 12 min under blue-light illumination and approximately 4 min under visible light or NIR illumination. - DISCUSSION AND CONCLUSION - The multispectral camera setup allows the capture of whole body datasets in an extended spectral range within a few minutes. With the help of photogrammetry software, textured 3D models for different spectral ranges can be reconstructed. Multispectral 3D whole-body imaging in line with postmortem CT examinations allows the combination of multispectral information from external body documentation with radiological findings from internal body documentation. Multispectral 3D documentation extends the postmortem forensic documentation of the deceased, as it detects (and documents) latent evidence on the body and textiles and can assist in detecting subcutaneous injuries and bruises on the body.
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This represents one of several sections of "A Bibliography Related to Crime Scene Interpretation with Emphases in Geotaphonomic and Forensic Archaeological Field Techniques, Nineteenth Edition" (The complete bibliography is also included at This is the most recent edition of a bibliography containing resources for multiple areas of crime scene, and particularly outdoor crime scene, investigations. It replaces the prior edition and contains approximately 10,000 additional citations. As an ongoing project, additional references, as encountered, will be added to future editions. From an archaeological perspective, numerous resources regarding the retrieval of blood and other types of trace evidence from historic and prehistoric contexts are included in this category. The compiler wishes to reinforce that evidence exposed to the elements, or deposited years prior to discovery may retain significant information capable of impacting the interpretation of a crime scene. Both here and in the sections of DNA Evidence and Stable Isotope Analyses, several citations may be found which should demonstrate for the crime scene investigator that assumptions should never be made that blood and body fluid evidence is completely obliterated from older scenes. Loy and Wood, (1989), is an early example of how blood evidence remained viable over thousands of years. That approximately 9000 year old evidence from Cayonu Tepesi in Turkey was initially realized using one of the most basic presumptive test for blood in most crime scene technicians' tool boxes - Hemastix. Again, the section on DNA Evidence contains numerous citations expounding on work such as Loy and Wood. Analyses of prehistoric trace evidence is now common in archaeological and forensic literature. A large part of this section deals with the reconstruction of violent crime scenes based on the shape, size, and position of blood spatter, or blood stain, evidence. Primarily considered at indoor crime scenes, the same type of reconstruction could apply to outdoor scenes but becomes more difficult given the effects of weather, and substrate movement. Works such as those of MacDonnell, (1997); Bevel and Gardner, (2001); and James, Kish, and Sutton, (2003), have served to expose criminal investigators to the stories represented in patterns of what would appear to most of us as bloody Rorshak tests. Those same works and others included in this section should also demonstrate the pitfalls of interpreting blood stain evidence without adequate training, experience, and certification. Probably the the most cross-referenced citations in this section have to do with DNA research; however, the researcher is also directed to sections on Photography, Fingerprint, Ear Print, Lip Print, and Tattoo Evidence, Firearms and Toolmark Evidence, Shoe and Tire Impression Evidence, and General Crime Scene and Death Scene Investigation Topics, for techniques in recording blood pattern evidence and bloody transfers in form of patent and latent prints involving body and clothing segments.
Invisible radiation imaging provides important insights into evidence normally beyond the visual experience of investigators. Reflected ultraviolet (UV) photography has classically been used for recording bite marks, bruises, car panel damage and fingerprints. The recent application of UV digital imaging potentially provides many advantages for forensic investigation as images can be viewed in real time at a crime scene, potentially enabling efficient collection of critical evidence that previously went unseen. However, since UV imaging collects data that is beyond our normal frame of reference for interpreting results, it is important that robust methodologies can be applied to quantify relative reflectance from different elements of a potential crime scene. We discuss the dynamics of the non-linear relationships between reflected radiation and the response of commercial grade image sensors that are typical in forensic practice, and how the implementation of image processing algorithms based on non-linear functions enables the recovery of robust linearized data for the precise quantification of reflectance in a scene. We demonstrate the application of this process with both a typical (fingerprint) and novel (material identification based on its reflective properties) problem for forensic imaging, and discuss how this linearized process will allow for the accurate documentation of reflected UV imaging as evidence in court proceedings.
One of the most important and commonly encountered evidence types that can be recovered at crime scenes are biological fluids. Due to the ephemeral nature of biological fluids and the valuable DNA that they can contain, it is fundamental that these are documented extensively and recovered rapidly. Locating and identifying biological fluids can prove a challenging task but can aid in reconstructing a sequence of events. Alternate light sources (ALS) offer powerful non-invasive methods for locating and enhancing biological fluids utilising different wavelengths of light. Current methods for locating biological fluids using ALS's may be time consuming, as they often require close range searching of potentially large crime scenes. Subsequent documentation using digital cameras and alternate light sources can increase the investigation time and due to the cameras low dynamic range, photographs can appear under or over exposed. This study presents a technique, which allows the simultaneous detection and visualisation of semen and saliva utilising a SceneCam 360° camera (Spheron VR AG), which was adapted to integrate a blue Crime Lite XL (Foster + Freeman). This technique was investigated using different volumes of semen and saliva, on porous and non-porous substrates, and the ability to detect these at incremental distances from the substrate. Substrate type and colour had a significant effect on the detection of the biological fluid, with limited fluid detection on darker substrates. The unique real-time High Dynamic range (HDR) ability of the SceneCam significantly enhanced the detection of biological fluids where background fluorescence masked target fluorescence. These preliminary results are presented as a proof of concept for combining 360° photography using HDR and an ALS for the detection of biological stains, within a scene, in real time, whilst conveying spatial relationships of staining to other evidence. This technique presents the opportunity to presumptively screen a crime scene for biological fluids and will facilitate simultaneous location and visualisation of biological evidence.
With increasing frequency the art of tattooing is permeating Western culture. In the United States, this rise in popularity has been accompanied by the adoption of more personalized and intricate designs; hence tattoos are becoming increasingly useful as tools for personal identification in medicolegal settings. Although pathological examinations indicate tattoos become more distinct given removal, or slippage, of the epidermal layer and/or following saturation with a 3% hydrogen peroxide solution, information on the degenerative change of tattoos during the postmortem interval has not been presented. This technical note provides an assessment of tattoo enhancement methods and presents a new method to enable better recognition of tattoos during the postmortem interval. Our results indicate certain tattoos remain visible and identifiable given extensive soft tissue decomposition. The use of an alternative light source proved most useful in illuminating tattoo inks throughout decomposition.
The detection of semen on the skin of children who present within 72 hours of an episode of sexual assault is critical to medical, forensic, and legal personnel. The Wood's Lamp, a UV light that causes semen to fluoresce, and four forensic laboratory techniques were compared to determine their sensitivity and decline in sensitivity over time. A descriptive study. Eleven adult female volunteers. Semen was placed on the skin of the volunteers. Samples of the dried semen were assessed during a 28-hour period with the Wood's Lamp, microscopy, the acid phosphatase assay, and two assays for the prostatic protein p30 (counterimmunoelectrophoresis and enzyme-linked immunosorbent assay). The intensity of the Wood's Lamp fluorescence of semen diminished dramatically by 28 hours; in contrast, the fluorescence of urine persisted up to 80 hours. Over time, the p30-enzyme-linked immunosorbent assay technique was more sensitive than microscopy, the acid phosphatase assay, and p30-counterimmunoelectrophoresis in detecting semen on skin. The Wood's Lamp is not a sensitive screening tool and should be used with caution. To improve the detection of sexual abuse in children, we recommend that the p30-enzyme-linked immunosorbent assay be used because of its potential as a more sensitive assay than those in current clinical use.
Photoluminescence spectra of dry untreated semen have been measured and a suggested method for rapid detection of untreated semen stains is derived from these measurements. The method is presented in the form of a flow chart to cover most crime scene situations. The absorption spectrum of dry untreated blood has also been measured and a suggested method for enhancement and photography of blood stains is derived from this measurement. The method is presented in the form of a flow chart. Both methods are based on the use of a high intensity light source such as the Polilight.
The use of ultraviolet light (UVL) to study and document patterned injuries on human skin has opened a new frontier for law enforcement. This article discusses the photographic techniques involved in reflective and fluorescent UVL. Documentation of skin wounds via still photography and dynamic video photographic techniques, which utilize various methods of UV illumination, are covered. Techniques important for courtroom presentation of evidence gathered from lacerations, contusions, abrasions, and bite marks are presented through case studies and controlled experiments. Such injuries are common sequelae in the crimes of child abuse, rape, and assault.
Evaluation of the detection capabilities of both laser and ultraviolet light sources was performed. The Spectra-Physics Model 171-19 argon ion laser was used in a comparison with the hand held Mineralight multiband ultraviolet lamp, Model UVSL-58 and the Fotodyne Foto UV 410, Model 3-4100. Both techniques were evaluated as to their detection limits for various biological stains. A serial dilution was made from semen, saliva, and sweat samples and their corresponding stains were examined under laser and ultraviolet light sources. The techniques were also evaluated as to possible interferences which may arise based on the type of fabric the stains were made on. The advantages and disadvantages of each technique in relationship to their initial costs are discussed.
The use of ultraviolet light induced fluorescence as an aid in forensic medical examinations of rape victims was evaluated preliminarily in a retrospective, non-consecutive study. In a four-month period, 17 cases were referred by the police for examinations at the Institute of Forensic Pathology. Ultraviolet light illumination (UVI) was used in seven cases, and in six cases fluorescent skin areas were observed. The fluorescence was due to lesions in four cases and stainings with saliva and semen in other two cases. In at least two cases, skin trauma detected with UVI were unobserved in ordinary light. It is concluded that UVI should be a routine part of forensic medical examinations. It may assist the forensic medical examiner in finding skin trauma and in locating stains, thus enabling retrieval of material for serological analyses. UVI is simple to carry out, requiring only a small, portable ultraviolet light source.
Recent investigation regarding the optical properties of human skin has lead to studies measuring autofluorescence, absorption, and reflectance of monochromatic light during exposure both in vitro and in vivo environments. The Stokes Shift deviation in absorbed and reflected light energy that occurs when skin is illuminated by 450 nanometer visible blue light can produce an augmentation in the appearance of pattern injuries when viewed through colored blocking filters. This paper demonstrates a comparison between photographic appearances of several bitemarks inflicted on living and deceased persons to determine the corroborability and usefulness of fluorescent versus full spectrum visibility of bitemark pattern injuries.
The accurate detection of semen is critical to forensic, medical, and legal personnel. The Wood's lamp (WL) emits ultraviolet light (UVL) and has been identified as useful in rape evaluations because it is purported to cause semen to fluoresce. This study was intended to determine if semen can be distinguished from other products by WL analysis. Investigators reviewed the previous training and frequency of use of the WL by emergency medicine and pediatric emergency medicine physicians at 2 medical centers. The participants were asked to use a WL to distinguish between a semen sample (<6 hours old) and 13 commonly used products. Next, 29 semen samples were collected and evaluated under high-power microscopy and under UVL. A total of 41 physicians participated in the study (68% male). The number of years practicing in an emergency setting spanned from.3 to 25 years with a mean of 7. 1 years. A total of 51% of participants trained in emergency medicine, 23% in pediatrics and pediatric emergency medicine. A total of 22% reported formal training in the collection of forensic evidence. A total of 62% of the physicians believed they have identified semen in the past; one third felt they could differentiate semen from other products under UVL. None of the 41 physicians were able to differentiate semen from other products using a WL. Moreover, the semen samples used for the study did not fluoresce under WL analysis. None of the 29 semen samples fluoresced whether wet or dry. The medicaments most commonly mistaken for semen were A&D ointment (Cardinal Health, Inc, Dublin, OH), Surgilube (Division of Atlanta, Inc, Melville, NY), Barrier cream (Carrington Laboratories, Inc, Irving, TX), and bacitracin (Division of Atlanta, Inc, Melville, NY). Participating physicians were unable to distinguish between semen and other common products, using the WL. Although the WL has been purported to be a useful tool as a screening device for the detection of seminal stains, the investigators have found it to be unreliable. Semen, previously reported to fluoresce under WL analysis, does not appear to do so. The correct identification of semen may be complicated by the presence of previously existing ointments and creams, some of which may be iatrogenically introduced (ie, Surgilube).
The Wood's lamp (WL) has been used in sexual assault evaluations. Recent data have shown that semen does not fluoresce with a WL and that physicians are unable to differentiate semen from other common medicaments using a WL. To determine whether physicians could differentiate semen from other products using an alternate light source (ALS), and to investigate whether a brief training period with the ALS would enhance physicians' ability to differentiate between semen and other commonly used products. An ALS, Bluemaxx BM500, was found to cause semen to fluoresce. Physicians were first asked to use this ALS to identify semen and then to distinguish between a semen sample and other products. Physicians then received a training class on the use of the ALS and were then asked to differentiate semen from other products. All physicians identified the semen as fluorescing and 25% successfully differentiated the semen from the other products using the ALS. Products most commonly mistaken for semen were a hand cream, Castille soap, and bacitracin. After the training session, 83% of the physicians successfully differentiated the semen from other products. The ALS, while not specific for semen identification, was 100% sensitive for it. Physicians instructed in the use of an alternate light source (BM 500) are able to identify semen as fluorescing and can differentiate semen (after a training session) from other commonly used products.
Providing the tools to fight crime
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Sirchie. (n.d.). Providing the tools to fight crime. Web site: URL