Abstracts From Fall 2000
No toxicology papers were submitted.
1. The Inadequacy of Instrumental “Mouth Alcohol” Detection Systems in Forensic Breath Alcohol Measurement
Rod Gullberg, Washington State Patrol Breath Test Section
811 East Roanoke Seattle, WA 98102
“Mouth Alcohol”, resulting from regurgitation or recently consumed alcohol, has long been a concern in forensic toxicology because of the potential for biasing an end-expiratory breath alcohol measurement. Manufacturers of forensic breath alcohol instruments have attempted to address the issue in part by developing software algorithms that attempt to identify ‘mouth alcohol” and abort the test if detected as present. These algorithms (as in the case of the BAC Datamaster, National Patent Analytical Systems, Inc.) generally evaluate the slopes of the breath alcohol expirogram and will abort the test if the slope is sufficiently negative.
Experimental breath alcohol expirograms were collected from drinking subjects both with and with out the presence of “mouth alcohol”. The data reveals that for subjects already having measurable breath alcohol, biases can exist in end-expiratory measurements and remain undetected by the “mouth alcohol” detection algorithm within the BAC Datamaster instrument. These biases occur at approximately five minutes after exposure to “mouth alcohol” because the expirogram does not conform to that assumed by the instrumental algorithm. These biases are unlikely to occur in sober subjects. Rather than relying on instrumental features to minimize the risk of “mouth alcohol” bias, sound protocol employing a 15 minute observation period and duplicate testing will enhance confidence in results to a much greater extent.
1. Busted on the Job: Identification of Wiring Harness
R.T. Wyant, M.S., Washington State Patrol Crime Laboratory
2700 116th NE, Marysville, Wa
A theft ring was discovered where vehicles were stolen and stripped. In the process the wiring harnesses to the doors were cut. Later the impounded frame was bought by the subjects at auction. The vehicle was reassembled with the stored parts and resold. During the reassembly, the wiring harnesses for the doors were spliced together with electrical tape.
The wiring harness was dissected and examined. We can identify the wiring harness as being the same original part using marks on the individual strands of copper wire. Due to the manufacturing process of the wire, extrusion marks alone on the insulation cannot be used for identification.
1. Applications of Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) for Elemental Analysis of Forensic Samples
Elzbieta (Ela) Bakowska and Steve Sibley
The application of laser ablation (LA) becomes more used as a way of sample introduction into ICP-MS. Laser ablation practically requires no sample preparation, and the sample-to sample analysis time is in the order of several minutes. One of the main limitations of the use of a standard ICP-MS instrumentation (without a laser ablation system) for forensic applications is the sample preparation. The traditional way of introducing a sample into ICP-MS is by aspirating the sample solution. If the original sample is available as a liquid, usually a minimal treatment (dilution and acidification is required). Solid samples require additional steps in converting them into a liquid form. Those extra procedures are potential sources of contamination, loss of the analytes, require more time, and may also require use of hazardous chemicals and additional sample preparation apparatus. When only minuscule quantities of the forensic sample are available, an additional issue of utilizing the whole sample (practically destroying it) cannot be overlooked. Additional advantage of using laser ablation ICP-MS is that even for extremely small quantities of the evidentiary material not all sample needs to be used (therefore the method could be labeled as “almost non-destructive”). The main disadvantages of the technique are the lack of calibration standards for most of the matrices, and the manual mode of operation (no autosamplers are available).
The examples of analysis of glass fragments, ink on paper and hair samples will be presented.
1. Post Crime Scene Clean-up
What we do: Bio Clean LLC cleans up and disposes of bio-hazardous material from trauma scenes, crime scenes, natural causes of death or injury. We clean commercial sites, vehicles, and residential environments. The contaminated area is cleaned, sanitized, deodorized, and prepared for renovation. Bio hazard waste materials are collected, properly sealed, labeled, removed and transported for appropriate disposal at a medical waste facility.
Qualifications: Bio Clean LLC complies with all OSHA and WISHA regulations. We are trained in disease transmission prevention (PDT), bloodborne pathogen certified, and our procedures are effective against dangerous pathogenic species including HIV-1 (associated with AIDS) and Hepatitis-B Virus (HBA). Bio Clean LLC takes precautionary measures by wearing protective clothing, respirators, and all associates are immunized against Hepatitis B.
Bonded and Insured: Bio Clean LLC is a fully licensed, bonded and insured contractor. We frequently work with Law Enforcement, Insurance Companies, Property Managers, Commercial Companies, and Government Agencies to provide bio-hazard waste removal services. Bio Clean LLC is a member of the American Bio Recovery Association, ABRA, a non-profit trade association, which promotes education, proficiency, and ethical standards for bio-recovery services. Members are sworn to uphold the highest levels of industry performance.
2. Heavy Metal Holiday Weekends
Terry McAdam, Washington State Patrol Crime Lab–Tacoma
A middle-aged Seattle-area woman was reported missing by her son after the Memorial Day weekend in 1997. An examination of her apartment by the Washington State Patrol Crime Scene Response Team revealed a small amount of blood on her bedding. This bedding, together with other items, was taken into evidence. The body of the woman was recovered several months later. Over the Independence Day weekend, another Seattle area woman was reported missing. Her body was not recovered until early August. Both bodies were too decomposed to permit a cause of death to be attributed at autopsy.
The debris from the bedding and other items from the first victim’s apartment, together with the clothing of both victims was collected and examined using a stereomicroscope. It was quickly apparent that all of the items retained small fragments of shiny metal. Some of these fragments showed evidence of grinding and polishing. The police interviewed a machinist (and part-time rock musician) who was the boyfriend of the first woman’s daughter. He was subsequently discovered to be a childhood friend of the second victim.
The clothing and material collected from the machinist’s vehicle, as expected, contained numerous fragments of metal. These were then compared to the collected items from the victims. Fibers from victim and suspect items were also compared.
This paper will discuss the characterization of the metal fragments and fibers that were encountered in these cases that contributed to the suspect being found guilty and subsequently being sentenced to life imprisonment without parole.
No Arson papers were submitted.
No Wildlife forensic papers were submitted.
1. Effects of Dry Cleaning on Semen Deposits
Kerstin M. Gleim Emerald City Forensics, Inc. 2400 6th Ave. S., Suite 255
Seattle, WA 98134 Telephone: 206-623-0644 E-mail: firstname.lastname@example.org
Do dried semen deposits on clothing survive the dry cleaning process so that a forensic scientist can 1) detect it, and 2) confirm its presence? It has been documented in the literature that acid phosphatase, the protein used to detect semen, gets washed away in water. Therefore once a garment gets laundered, a forensic scientist may not be able to detect the presence of a semen deposit if deposited before the garment was washed. Dry cleaning is another cleaning process that is used exclusively on a number of fabric types and is optionally used on fabric types that can also be washed with water. It would be useful to know the effect of dry cleaning on semen deposits.
To answer the question, two rayon fabric pieces were spiked with semen from a normal spermatozoa producer, the areas marked with a waterproof marking pen, one piece sent to the dry cleaners and the other kept as a control. In Washington State, dry cleaners almost exclusively use tetrachloroethylene (also known as perchloroethylene or “perc”) due to state regulations. After the dry cleaning, both fabric pieces were tested in the usual way that semen examinations are done.
The results were: 1) the pen marks on the dry cleaned fabric piece were partly obliterated indicating that the fabric had indeed been through the dry cleaning process, and 2) there were no differences in the testing results for the non-dry cleaned fabric and the dry cleaned fabric. Semen deposits on both fabrics yielded strong positive results with the reagent for acid phosphatase, both had positive results with the p30 membrane test at the same dilutions, and both had 4+ spermatozoa.
The dry cleaning process used in Washington State does not remove semen deposits from this type of rayon fabric; that is, it does not remove any of the target components that we in the forensic community use to find and confirm the presence of semen.
Therefore, a semen deposit on a garment that has only been cleaned by the dry cleaning process may not be “dated” by its cleaning schedule without further testing the particulars of the case.
Further work needs to be done to test a variety of fabrics and to test other variations of the dry cleaning process such as the effect of standard preliminary spot treatments used by dry cleaners.
2. Correlation Between Amylase Assay and DNA Results From Saliva Stains
Brook E. Clark and Lori E. Hutchinson
Montana Forensic Science Division
PCR based DNA analysis has revolutionized the individualization of saliva stains by allowing the generation of highly discriminating DNA profiles from buccal cells sloughed from the salivary donor. Despite these advances several limitations still plague this analysis. Saliva stains contain only minute amounts of cellular material and the stains are invisible to the naked eye. Consequently, sampling saliva stains for DNA extraction is difficult, and DNA results can vary dramatically. An assay that would help pinpoint and area of a saliva stain where optimal DNA results can be obtained would be useful. The most commonly used screening assay used in the presumptive identification of saliva is the amylase diffusion assay. This technique assays for the presence of high levels of amylase, and enzyme found at high concentrations in saliva. In this study we explore the correlation between DNA results and Amylase Diffusion Assay results hoping to answer this question: Can the amylase assay be used at the screening level to optimize sample selection for DNA analysis? We used a commonly encountered forensic sample as our model system–sealed envelopes. Samples from several controlled studies were assayed for amylase activity and DNA results. Data from these studies will be presented along with empirical information taken from actual casework.
3. The Shorts, The Condom and The Substrate Control
Lori E. Hutchinson
Montana Division of Forensic Science
A case involving a sexual assault, a consensual partner and an unusual result from a substrate control will be presented. I will present our lab’s approach to this situation and the steps that were taken to explain and support the conclusions of the analysis. However, I am particularly interested in hearing how other labs would have handled a similar situation.
4. Validation of the Applied Biosystems Profiler Plus and Cofiler Amplification Kits for Use in Forensic Casework
Jeremy Sanderson WSP Crime Laboratory–Tacoma, WA
Before utilizing recent advances in forensic DNA technology which allow for more sensitive and more discriminating testing, laboratories must perform validation studies to demonstrate that reliable and reproducible results can be obtained. The 13 short tandem repeat (STR) DNA sites, along with the gender determination site amelogenin, tested by Applied Biosystem’s Profiler Plus and Cofiler amplifications kits have been evaluated for forensic DNA profiling using Applied Biosystems 310 Capillary Electrophoresis units.
One set of experiments was aimed at retaining flexibility in the profiling procedure when working with minute quantities of DNA. To this end, various studies were performed. First, an assessment of the minimum quantity of DNA required for successful amplification was made. Two options for varying the amount of amplified product DNA injected onto the capillary were then examined. Results of varying the injection time from the standard of five seconds (from 1 second up to 40), as well as varying the amount of amplified product loaded into the formamide denaturant (from 0.75ul up to 7.5ul) were evaluated. Protocol guidelines for acceptable injection times and amplified product volume were established based on the results of these studies.
A round-robin study was performed in collaboration with the Alaska, Las Vegas, Utah, Portland and Reno crime laboratories to demonstrate the reproducibility of testing among different forensic agencies. Each laboratory submitted 10 bloodstains which had been typed previously. The bloodstains (fifty in all) were collected and redistributed for testing. Results of both Profiler and Cofiler profiling by each laboratory were collated and found to be consistent throughout.
Other routinely examined validation issues such as reproducibility between repeat injections, stutter percentages and heterozygote peak height ratios demonstrated across the multiplex loci were also addressed as part of this validation.
1. Conceptual Tools for Making Casework Decisions
Kerstin M. Gleim Emerald City Forensics, Inc. 2400 6th Ave. S., Suite 255
Seattle, WA 98134 Telephone: 206-623-0644 E-mail: email@example.com
How do we make decisions about casework: what evidence to examine and in what order, what tests to use, and how to evaluate the results? All of us make these decisions daily. Doing a thorough job on a case does not mean examining everything or doing all possible analyses. But how do we make defensible decisions to choose among the possibilities? If asked how these decisions are made, for example if you were asked to write a protocol or asked to defend your decision by your supervisor or in court, would you be able to articulate the tools that you use? This paper will offer several formal conceptual tools that can be used to make effective case decisions, with references to related literature articles.
2. Examination of a Drum Microscope and its Accessories, Circa 1833
William M. Schneck
Washington State Patrol Crime Lab
W. 1100 Mallon, Public Safety Building
Spokane WA 99201
An antique functional microscope, circa 1833, with an assortment of lens, magnifiers, live well, ivory sliders (prepared microscope slides) and literature from the period will be discussed. A microscopical examination of many of the specimens including iridescent insects, minerals, pigments, DNA and botanicals will be characterized using PLM and SEM-EDS.