PURPOSE
The purpose of this experiment is to determine the possibility of using multiple forensic science methods to solve a crime.
I have always wanted to do a science experiment that involves cosmetology. My dream is to be a nail artist but there is no one around here to guide me through the science of nail products. I am also interested in forensic science and am a “C.S.I”, “Num3ers”, “House” junkie. I simply got thinking and came up with a way to study both forensics and cosmetics at the same time.
The information gained from this experiment could potentially solve a serious crime. These methods are used in this experiment are basic versions of what they actually perform in real crime labs. A forensic scientist could really solve a horrific murder by such simple evidence such as the lipstick and latent prints found at the scene of the crime. A possible career path for me is to become a forensic scientist. The skills I learn in this experiment may help me pursue a career in forensic science. Careers in law and criminal science need to know the basics of obtaining and processing basic evidence such as the latent prints and chromatography, which my research and experimentation involves.
HYPOTHESIS
I hypothesize that the perpetrator (suspect) will be identified by lip print identification and chromatography methods.
I base my hypothesis that a suspect can be identified by lip prints by an article written by Thurman Ray Williams titled “Lip Prints – Another Means of Identification.” The article stated that lip prints were similar to fingerprints and that people can be identified by their lip prints.
I base my hypothesis that a suspect can be identified by chromatography because the evidence (lipstick) can be broken down into two or more pure substances that are physically close together. Chromatography is used to solve many different crimes (Martha Stewart’s insider trading, Oklahoma City Bombing, D.U.I.’s, and arson cases) by testing wide varieties of substances. If that many diverse substances can be processed for criminal evidence using chromatography, then lipstick too can be broken down to its basic components and used to solve a crime.
The Experiment design is in two parts: latent lip prints and chromatography of lipstick. This is because there are essentially two experiments performed to retrieve data that used to determine the solution to the problem.
Latent Lip Prints
The constants in the latent lip print study are:
The method of lifting the lip print.
Tape used to lift the lip print.
Camera, film, and setting of the photography of the lip prints.
The objects the lip prints are lifted from.
The “perpetrator”.
The manipulated variables are:
The lipstick’s shade and manufacturer.
The test suspect’s individual lip structure.
The test suspect’s method of applying lipstick.
The test suspect’s method of kissing the object to be tested.
The responding variable is the number of matching focal points of reference to the control sample.
To measure the responding variable the lip prints are observed via naked eye, & hand lens. The lip prints are photographed with a 35mm camera. The film is developed and put on CD and print photographs are made. The photographs, on CD and print, are compared to the raw data. Comparisons are made between the lip prints on glass and the lip prints on paper. The suspect’s data is compared to the control (perpetrator).
Chromatography of Lipstick
The constants in the chromatography study are:
The brand of the chromatography paper
The size (length and width) of the chromatography paper strip.
The individual test tubes used.
Brand and amount of acetone used.
Size of dot of sample lipstick used.
Time each sample is processed in the acetone solution.
The “perpetrator” and the lipstick she used.
The manipulated variables are the shades and manufacturers of the lipstick, and any residue (food, lip-gloss, or medication) that might be on the suspects’ or perpetrator’s lips.
The responding variable is the distance the solvent and the lipstick components moved up the strip of chromatography paper.
To measure the responding variable the distance the solvent and each lipstick component is measured and compared to each other and the control (perpetrator).
11 tubes of lipstick
4 tubes of 3 different shades and manufacturers, only 11 will be selected.
9 mirrors
9 small sealed envelopes
8 large envelopes to distribute supplies to the subjects.
135mm camera and 400 asa film
1 Fingerprinting kit from BSA for the Pre-Experiment stage
12 strips of chromatography paper
4 additional strips of chromatography paper
1 scraps of chromatography paper
4 additional scraps of chromatography paper
1 Metal knife
1 pair of scissors or paper cutter
12 test tubes
1 Test tube holder
1 can of commercially available acetone (from hardware store)
1 Pencil
1 Sharpie pen
1 Hole punch
1 pair of eyeglasses or safety goggles
1 Stopwatch or watch with second hand
1 Ruler
1 Calculator
1 Spool of black thread
1 Roll of Scotch tape
1 Roll of masking tape
1 Roll of paper towels
1 Old container of commercially available acetone or similar style empty &
clean
container.
Pre-Experiment Phase
1. Purchase single tubes of different colors and manufacturers of lipstick to test to determine if the lipstick will be acetone solvent. Four tubes were purchased for this phase of the experiment.
2. Prepare chromatography paper to test by cutting into strips narrow enough to fit inside the test tubes without touching the sides. A hole is punched at the top of the strip and a thread is tied to the top of the strip using a monk’s head knot. Each strip is labeled with it’s test number with a pencil on the top edge.
3. 1 test tube and 1 strip of chromatography paper is needed to test each individual tube of lipstick.
4. Punch a hole in a scrap piece of chromatography paper and place over the strip of chromatography paper to be used in the test.
5. Smear lipstick, stencil method, onto the chromatography paper using the punched hole as a guide 1cm from the bottom of the strip.
6. Using a Sharpie pen, make a small line 1/3rd from the bottom of the test tube.
7. Pour commercial grade acetone to the line of each test tube, over a steel sink, taking care not to spill. Place each test tube in the test tube holder.
8. Carefully lower the chromatography strip with the lipstick circle on it into the acetone, taking care not to dip the lipstick in the acetone. Only the chromatography paper should touch the acetone. Tape the thread to the outside of the test tube to secure. Tape a second piece of tape to the top of the tube to prevent evaporation.
9. With a stopwatch, record when you first see the chemical components stop moving. Remove chromatography strips if after 15 minutes there is no change.
10. Carefully remove the tape and chromatography paper.
11. Place the processed chromatography strips on a folded piece of paper towel for absorption.
12. Pour the used acetone from the test tubes into a second can to store for disposal later.
13. The chromatography strips are examined to determine if the chemicals present did break down and separate in commercial acetone. Three manufacturers are chosen for the experiment phase. 12 tubes, four of each manufacturer is purchased. Chosen shades are close in color.
14. Evidence cards are made on cardstock to mount the lifted lip prints. See appendix.
15. Lifting of latent lip prints is practiced using the BSA Fingerprinting kit and latent print tape.
Experiment Phase
1. Preparation of Materials
a. With help from a non-biased individual, assign each test suspect a number. Have the non-biased individual record the number and their name in a way that it will not be disclosed unless a supervisor or teacher needs it.
b. Label 8 envelopes with the test suspect’s number.
c. Label 8 tubes of lipstick with the test suspect’s number at random.
d. Label 8 compacts with the test suspect’s number. Label the ninth compact as “Control” and “Who dun it”. Open each compact. Clean each mirror. On the magnified mirror in each compact, place a tiny question mark written on masking tape. On the opposite mirror in each compact, place a tiny “x” written on masking tape. X=kiss.
e. Seal 9 envelopes. Label 8 envelopes with the test suspect’s number discreetly in a corner. Label the 9th envelope as “Control” discreetly in a corner
f. In the envelopes, place the corresponding lipstick, compact, and sealed envelope. Have the non-biased individual secretly place the control or perpetrator compact and sealed envelope in one of the 8 labeled envelopes of their choice. Have them remember whose envelope they selected but remind them they are not to disclose the information until after the experiment is complete and the results are documented.
2. Obtaining Evidence
a. Bring prepared envelopes to school.
b. Non-biased individual is given envelopes to hand out to the participants. This individual is instructed in the procedure the participants must follow in case they are confused. The selection of this method is to eliminate the amount of time the participants must be out of their classroom to participate in the extracurricular experiment. The individual is able to provide excused hall passes to allow students into the restrooms and back to class during class time.
c. On Valentine’s Day, give each participant a letter explaining the procedure they will need to follow when they participate in the experiment. A letter to the individual’s teacher is also provided requesting that they allow their student to go to the non-biased individual at a convenient time during their teacher’s class to participate in the experiment. The procedure is explained as follows:
What You Do:
1. I will send you down to my mom (a.k.a. mean old attendance lady) to do the “kissing” because I cannot know who the “criminal” is.
2. My mom will give an envelope full of stuff that is listed above.
3. Take out the compact and the tube of lipstick (you can use the mirror).
4. Open the compact. There are two mirrors inside of it. Two pieces of masking tape will be in the corner of both mirrors. The piece of tape with the “X” on it is the mirror that you kiss. When you kiss, apply two coats of lipstick together, and rub lips together. Then kiss the mirror.
5. On the other mirror put a question mark on it with the lipstick. Yes with the lipstick. I know that it sounds crazy but trust me. Don’t be shy be bold in your writing. I will scrape this lipstick off to test it.
6. Close the compact and the tube of lipstick and put them back in the envelope. If there are two compacts in your envelope then you were selected to be the “criminal”. If you were chosen then repeat steps 3-5.
7. There is a sealed envelope folded in half. All you need to do with it is kiss the back of it and put it back in the envelope. This is the “love note”. If you received two compacts, you would have also received two sealed envelopes. You need to kiss the second envelope in the same manner as you kissed the first one.
8. Put everything back in the envelope and give it back to my mom, and know you can go back to class. She will write you an excused pass.
d. Individual participants go to the non-biased individual, obtain their envelope. The non-biased individual reviews the procedure to the individual participants as written. The participants return to class.
e. The envelopes are secured and an appointment is made to schedule the Designated Supervisor to run the experiment.
3. Processing the Evidence
a. Prepare chromatography paper to test by cutting into strips narrow enough to fit inside the test tubes without touching the sides. A hole is punched at the top of the strip and a thread is tied to the top of the strip using a monk’s head knot. Each strip is labeled with it’s test suspect’s number with a pencil on the top edge.
b. 1 test tube and 1 strip of chromatography paper is needed to test each individual tube of lipstick.
c. Punch
a hole in a scrap piece of chromatography paper and place over the strip of
chromatography paper to be used in the test.
d. Open compact #1. Photograph the question mark from each compact. Carefully scrape the lipstick from the question mark off of the mirror with a sharp knife
e. Smear lipstick, stencil method, onto the chromatography paper using the punched hole as a guide 1cm from the bottom of the strip.
f. Repeat steps d & e until all 8 test suspect’s and the control (perpetrator) evidence is prepared for processing.
g. Using a Sharpie pen, make a small line 1/3rd from the bottom of the test tube.
h. Pour commercial grade acetone to the line of each test tube, over a steel sink, taking care not to spill.. Place each test tube in the test tube holder.
i. Carefully lower the chromatography strip with the lipstick circle on it into the acetone, taking care not to dip the lipstick in the acetone. Only the chromatography paper should touch the acetone. Tape the thread to the outside of the test tube to secure. Tape a second piece of tape to the top of the tube to prevent evaporation.
j. With a stopwatch, record when you first see the chemical components stop moving. Remove chromatography strips if after 15 minutes there is no change.
k. Since the test tube holder only holds 6 test tubes, cover the remaining 6 lipstick samples with plastic wrap to prevent dust from settling on it, smearing, or evaporation.
l. Carefully remove the tape and chromatography paper.
m. Place the processed chromatography strips on a folded piece of paper towel for absorption.
n. Pour the used acetone from the test tubes into a second can to store for disposal later.
o. Repeat steps g to m for the final half of the lipstick samples.
p. All used acetone can be returned to original container for later household and eventual proper disposal as a hazardous waste.
q. Acetone is moved to the outside shed for proper storage.
r. The chromatography strips are visually examined to determine if the chemicals present did break down and separate in commercial acetone.
s. Photographs are taken of the strips to compare the differences and similarities between the strips.
t. The rate and distance of the breakdown of chemical components are calculated and recorded.
u. The lip prints from each test suspect’s lip print is lifted from their compact and mounted on an evidence card. They are not dusted prior to being lifted with latent print tape. The data on the card is completed.
v. The lip prints are photographed
w. The lip prints are compared using photography and a hand lens to note the differences and similarities. Data is recorded.
x. The experiment is complete and the test suspect’s lipsticks and compacts are returned to the individual for their private use.
RESULTS
The purpose of this experiment was to determine the possibility of using multiple forensic science methods to solve a crime. The goal was to prove that a “perpetrator” could be identified by their lip prints and the chromatography of the lipstick that they used. I hypothesized that these two methods, latent lip print identification, and chromatography could solve a serious crime.
Results of Latent Lip Print Identification.
Evidence proved that the perpetrator (control #1) was identified by their lip print. This was proven after careful comparison of the lip prints of the perpetrator (control #1) to the 8 suspects. The evidence providing the best documentation was the latent lip prints lifted directly from the lip print on the compact and placed on an evidence card. The lip prints from the envelope were only useful as a back up to the mirror method. Some prints on the compact were smudged and the envelope was a better match. Controls 2-4 were not used in this phase of the experiment except for visual comparison of the shade of lipstick.
To determine a positive match 10 matching reference points were found on both control #1 and suspect #8 from the lip prints on the evidence cards. Suspects #1-7 had only 1-2 matching reference points. The reference point marks were made on the mounted samples in contrasting colors. The reference dots, because of their size are not visible in the photography of the evidence cards. Below are the photographs taken of the latent lip print evidence:
The data of the reference points the suspects had in relation to the perpetrator are illustrated in the two figures below. It is obvious that Suspect #8 is the closest match to the perpetrator based on the number of reference points their latent lip prints showed.
Latent Lip prints are classified into six different classifications based on their characteristics. It is possible for a person to have more than one type classification of their lips. In this experiment the majority, five suspects, had three different type classifications, one suspect had two different type classifications, and two suspects had four different type classifications.
In addition, each lip characteristic classification was represented by the suspects at least three times. Class I characteristics were represented the most and therefore the most common classification of the suspects in this experiment.
Results of Chromatography Test
The results of the chromatography test supported that Suspect #8 was the perpetrator. The chromatography of Control #1 (Perpetrator) and Suspect #8 did not break down into analytes. The suspects who used the same lipstick as Control #2 and Control #3 were no longer suspects because their lipstick components perform as expected using acetone as the solvent.
Visual observation of the chromatography results match the following controls with the following suspects:
Lipstick sample Color Match
As you can see it appears that one more suspect used the same kind of lipstick as Control #4 than what was planned. There should only be a maximum of three suspects using each manufacturer of lipstick in this experiment.
Visual comparison of the chromatography strips shows some definite matches in first appearance (Figure 32). By color and chemical break down it appears that Control #3 and Suspect #7 match. It also appears that Control #2 will mach Suspects #1 and #4 based on color but the breakdown did not match since Control #2 had three components and Suspects #1and #4 have 4 components each.
Many different visual observations were made. The table below (figure 33) shows the visual observations of the latent lip print evidence and the chromatography evidence observations that were made for each control sample and suspect sample. The table also notes the similarities of the suspects to Control #1, the perpetrator. To support my theory that Suspect #8 was the perpetrator, the graph in figure 34 illustrates the high number of similarities in the evidence obtained to that of Control #1.
Visual Comparison of shade or color Comparison of the written "?" Comparison of the shape of lip prints Comparison of the classification of the lip prints Comparison of the lip print on the envelope Visual comparison of lipstick samples after chromatography Calculation of chemical components after chromatography (Rf= distance chemical traveled/ distance solvent traveled)
The table below (Figure 34) shows the data obtained from the chromatography experiment. The table shows the mathematical results when finding the Rf or Retention Factor and its similar calculation HETP. The data supporting the capacity factor (K’) and the selectivity factor (Ω) which too are closely related.
Retention Factor and HETP – The retention factor is one calculation that you may use to compare the elution of one component to that of another. It is essentially a percentage of the rate traveled by a chemical component; it is calculated as follows:
Rf = Distance traveled by one lipstick component / Distance traveled by the acetone
That is a very simple calculation instructed in Crime Scene Investigations, Walker & Wood but the data results were inconclusive. None of the suspect’s calculations came close to any of the control samples with the exception of those who used the Control #4 lipstick.
A similar calculation is HETP or Height Equivalent to a Theoretical Plate and was found in “Chromatography – Introductory Theory”. HETP is based on theoretical or imaginary plates that serve as a way to measure the column efficiency by counting the imaginary plates in a chromatography column. The calculation of HETP is as follows:
HETP = L/N
Or
HETP = length of the column of the analyte / number of theoretical plates in a column.
I obtained the data by placing the column in figure 34 up to the individual chromatography strips and counted the number of theoretical plates as described in the above calculation Suspect #1, #4, and #6 did not match Control #2 as I expected they should nor did Suspect # 7 match Control #3. Controls #1 and #4, Suspects #2, #3, #5, and #8 all matched because their lipstick would not break down in the acetone.
A second method that calculates the retention factor, which is also called the capacity factor calculates the migration rate of an analyte but uses time as a primary unit. This second calculation determines k’. k’ can be calculated as follows:
k’A = tR – tM / tM
or
k’A = retention time – time of mobile phase /time of mobile phase
Using this calculation obtained from “Chromatography – Introductory Theory,” I was slightly more successful in proving that the controls matched the suspect. By visual observation of color, Control #2 should have been the same as Suspects #1, #4, and #6. In the chromatography phase of the experiment, Suspect #6’s lipstick behaved the same as Control #4 and no components moved. This phenomenon again questioned the accuracy of the chromatography phase. However, Control #3 and Suspect #7 had identical calculations when k’ was calculated and the visual appearance of the chromatography of those two strips were a very close match.
After k’ is calculated for each component, the selectivity factor or Ω can be calculated. This calculation describes the rate that the separation of the components displays. To obtain this calculation I used k’ of the slowest analyte and divided it by the k’ of the fastest analyte on the individual chromatography strip. The calculation is as follows:
Ω = k’B / k’A
Once again, the calculations did not support what I had theorized. The calculation did not support the Suspects that I assumed used the same lipstick as Control #2. Since several controls and suspects did not break apart during chromatography, they had no data to calculate. Control #3 and Suspect did have the quotient proving that that the two samples had matching data after the chromatography calculations.
To summarize the chromatography results, most of the calculations were inconclusive in proving that the suspects matched their anticipated control. Control #3 and Suspect #7 were the only two samples that had data to support my visual observations. Suspect #8 still appears to be the perpetrator because the sample did behave the same as did Control #1 (perpetrator) and Control #4. Visual observation appears to be more accurate in this experiment than the calculations performed.
My hypothesis was that the perpetrator (suspect) would be identified by lip print identification and chromatography methods. The results of the experiment indicate that both the two hypotheses should be accepted.
Even though I was able to prove the perpetrator by both examination of latent prints and the chromatography of lipstick, most of the calculations of the chromatography were inconclusive and not accurate to prove someone guilty or innocent in a court of law. I believe that there are several factors that could have contributed to the inconsistencies.
The first reason for the inconsistencies could simply be the quality control of the lipstick itself. The pre-experiment lipstick manufacturer was one shade number different from the shade used in the experiment. Although the same brand manufacturing line was selected, the color originally tested was no longer available. Because it was the same manufacturing line, the only difference should have been the color and had the same base components in it. However, even if you purchase the same shade and manufacturer of expensive lipstick, every time for several years the color will differ from tube to tube because of its dye lot.
A second reason is the possibility that the suspects could have compromised their evidence just like a person would if they were trying to conceal their identity in a crime lab. The suspects could have done this with out even realizing it or telling me. This is very possible since the suspects included two sets of twins and five of the 8 suspects are very close friends.
A third reason is the incredibly small variances in the chromatography data itself. I am measuring with a ruler purchased from the local Wal*Mart while a real crime lab has special equipment and computer programs to do the measuring and calculations.
I understood the math, but I wonder if there were other calculations that I could have done that would have provided more accurate results but are too complicated for my 7th grade math level. Along that line, when I plotted the data on a line graph and inserted the results in my report, the graph did not truly match the data that was put in the supporting spreadsheet. The graph did show some interesting parallels in the data but no matter what I tried, two of the lines were definitely incorrect while the other 10 lines were accurate when I tested it on graph paper myself.
Above all, there is always human error when working with such small quantities of materials no matter what experiment or activity you are pursuing.
I do believe that the latent lip print evaluation was much more accurate. I knew as soon as the lip print evidence was lifted and placed on the evidence cards and matched who the perpetrator was. I was hoping to determine which suspects were the twins but had nothing to prove my theory. I had a hunch on two twins but the lip print on their hunch was still similar to another suspect’s. The other two twin suspects have motor skill “disabilities”, one with gross motor delays, and the other with fine motor delays. The motor skill issues could have made it difficult for them to provide evidence with out smearing or upsetting the evidence. I do think having the twins with the motor delays it was educational for me to be aware of the abilities of others. I considered the selection of the compact to make sure it was a style that they could open and handle easily. I made sure the plastic wrappings were off the lipstick tubes which could have been especially difficult for two of the suspects them to open by themselves. We learn so much by working with others.
My results should be useful to those interested in law or criminal justice because these methods of forensic science can help solve a serious crime such as a murder of kidnapping. In addition, chromatography principles could be used in medical fields as well to determine what substance a person has encountered that might be making them sick.
If I were to conduct this experiment again I would have the test suspects kiss a mirror without having applied lipstick then lift the lip print with graphite powder. I would have also tried to do third stage of the experiment in an actual crime lab or lab that regularly does chromatography. By performing the experiment in such a facility, I could have compared my results to a more standardized method. I would have also found someone who understood the math directly in relation to the chromatography experiment so I could learn the higher level math skills needed to perform other calculations involving chromatography.
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