Author Presentations: Wednesday, June 14
Abstracts are listed in order of author presentations on Wednesday, June 14. Abstracts and the presentation schedule are subject to change; check this page regularly for additions and updates.
MORNING
Do You Feel Lucky? Characterization of Shavings from Lottery Scratch Tickets
Brendan Nytes — Microtrace LLC
This talk stemmed from an unknown material that was submitted to our laboratory for analysis. The sample was described as “metal shavings” and was suspected to be related to illegal drug activity. The substance was initially recognized during a visual examination. The visual identification was later confirmed through a combination of microanalysis and scientific literature. This talk will discuss the case, our approach to this identification, and the analytical characteristics of various scratch-off tickets.
Tremolite/Actinolite Concentrations in Chrysotile
Eric J. Chatfield — Chatfield Technical Consulting Limited
There has been an ongoing controversy about the presence or absence of amphibole, such as tremolite or actinolite, in commercial chrysotile. When tremolite/actinolite fibers were first discovered to be a major contributor to the asbestos fiber content in lung tissues of former workers in the Quebec chrysotile industry, it was suggested that these fibers could be responsible for mesothelioma and lung cancer found in these workers, rather than a consequence of the much larger exposures to chrysotile. This proposal became known as “the amphibole hypothesis,” and it became of great interest to the U.S. personal injury litigation community. Although numerous measurements of tremolite/actinolite in chrysotile-containing commercial products have been made in support of litigation, very few measurements have been made on chrysotile from individual mines.
Microscopy in the Study of Asbestos-Containing Joint Compound
James R. Millette — Millette Technical Consulting
After World War II, drywall (wallboard, plasterboard, and gypsum board) became the common construction material for interior walls in buildings. Before the walls can be painted, it is common practice to seal the seams between the boards and cover nails with joint compound (mud, spackling, taping compound, or joint treatment material). Most joint compounds from the 1940s into the late 1970s contained chrysotile asbestos in various formulations with binding agents such as limestone, gypsum, and/or casein, and later, polyvinyl alcohol. The formulas also contained fillers such as quartz, attapulgite, kaolinite, perlite, talc, or mica. Analyses by PLM determined the chrysotile asbestos content of samples of Bondex and Georgia Pacific products to be 1-5% and 3-8%, respectively. No amphibole asbestos fibers were found in the Georgia Pacific product tested using the acid/base digestion preparation procedure. During simulation testing by MVA Scientific Consultants, the asbestos level in the breathing zone of the worker during mixing of Bondex Joint Compound ranged from 6.9 to 12 F/cc (PCM modified by TEM). The level was below detection during application. During sanding, the asbestos level in the breathing zone of the worker ranged from 1.9 to 5.5 F/cc.
3D Printing: Creating Enlarged Models for Communicating and Teaching
Kevin Brady — Tredegar Surface Protection LLC
Communicating microscopic findings with non-microscopist colleagues and students can be challenging. Enlarged 3D models of microscopical images can help one gain an appreciation for microscopical structures and concepts. Some three-dimensional images from a white light interferometer and enlarged models of the same images will be shared and discussed.
Microscopy and Microanalysis of Solution Dyed Fibers
Kelly Brinsko Beckert (presenting author), Otyllia Abraham, Ethan Groves, Brendan Nytes, Christopher S. Palenik, and Skip Palenik — Microtrace, LLC
The color of a fiber is an important and distinguishing feature exploited by fiber analysts throughout the various stages of a forensic fiber comparison. This includes not only microscopical examinations, but also microanalytical techniques to identify the colorants (in addition to the fiber-forming polymers). Our current research is focused on solution dyed (i.e., pigmented) fibers, which are colored by the addition of insoluble pigment to the liquid polymer prior to extrusion. Solution dyed fibers are becoming increasingly common due to a variety of factors, including their ability to withstand harsh cleaning agents, inherent resistance to fading, and environmentally friendly manufacturing methods. The number and colors of pigments utilized in a given fiber, their identity, particle size, and optical properties represent unexploited properties that can be used to evaluate fiber associations or provide investigative information during a fiber analysis. However, there have been no systematic studies of pigmented fibers, and therefore, no practical guidance is available to the bench-level analyst to identify, characterize, or interpret pigmented fiber evidence in forensic fiber cases.
To address this knowledge gap, a systematic study of 225 solution dyed fiber samples was undertaken. The selected fiber samples span major manufacturers, include various applications of solution dyed fibers, and represent the variety of colors and polymers that are produced. This presentation summarizes the results obtained through polarized light, oil immersion, and fluorescence microscopy. Analysis of this expansive dataset will be presented to explore and summarize the microscopical observations. This will include data concerning the number of pigment types detected within a given fiber, as well as enumerations of the trends in color, morphology, and fluorescence characteristics of individual pigment grains as a function of polymer and color. Initial insights related to pigment identification from bulk elemental analysis by energy-dispersive X-ray spectroscopy, microspectrophotometry, and Raman microspectroscopy of the pigments will also be discussed.
Microchemical Analysis of Lysergic Acid Diethylamide (LSD)
Jim Dunlop — Kalamazoo County Sheriff’s Office
The hallucinogenic compound lysergic acid diethylamide (LSD), formally associated with 1960s counterculture, has made a resurgence. The illicit psychedelic drug had faded into relative obscurity with the end of the hippie movement. However, there has been a marked increase in the use of LSD across the U.S. in the past 5 years.
With the increase of suspected LSD samples encountered in the crime lab, a check of the published data regarding microscopical analysis proved to be woefully inadequate. This presentation will focus on the use of polarized light microscopy and microchemical methods to identify LSD and will detail its history, including its origin, manufacture, and use.
AFTERNOON
A Tale of Two Residues: How Thoughtful Curation of Reference Materials Aid in Unknown Identifications
Otyllia Abraham — Microtrace, LLC
Chemical residues are a class of contaminants that can be found on a number of surfaces or products and in various forms such as films, discolorations, and collections of particles. The presence of these residues can result in consumer complaints, as well as failed quality assessments due to contaminated equipment or product batch rejections. The identification of a residue sample can help industry clients prevent recurrence when a source of the unknown residue, or the method of formation, can be determined.
Residues represent a challenging subset of samples due to a combination of factors, including: 1) the possibility of multiple components, 2) the matrix on which they are received, 3) the fleeting nature of some deposits, and 4) the interpretation of results to elucidate a potential source. Sample isolation and analysis is contingent on the matrix on which the residue is received and the nature of the residue itself. In order to fully characterize a residue, a suite of microscopical examination and orthogonal instrumental analyses are often necessary. Due to the complex nature of residue analyses, the determination of an origin is largely dependent on scientific interpretation of the components identified through microscopical examination and instrumental analyses. Interpretation of a residue containing multiple components is aided significantly by a knowledge of potential sources that may be used within a facility, such as detergents or lubricants. While a surficial knowledge of such sources may be gleaned through their Safety Data Sheets, the in-house analysis of these materials considerably increases the potential for a source determination.
This presentation explores two residue case studies and how the curation of common industrial detergent reference materials directly aided in a source determination.
Developing Automated Mineral Identification by SEM-EDS for Forensic Laboratories
Ethan Groves (presenting author), Jack Hietpas, and Christopher S. Palenik — Microtrace LLC
Despite its ubiquity, soil remains one of the most underexploited classes of physical trace evidence. This stems from a combination of a general knowledge gap of the probative value of soil evidence to link physical objects or people to locations and, a lack of training for analysts to conduct the often particle-based characterizations of minute amounts of soil. Automated mineral identification using scanning electron microscopy with energy dispersive X-ray spectrometry (SEM-EDS) coupled with R, an open-source statistical software package, provides a method that utilizes instrumentation and expertise that already exists in most forensic laboratories. Further, this method can provide quantitative compositional and mineral-count information to aid in the characterization and comparison of soil evidence.
This presentation discusses the analysis of several hundred specimens from Microtrace LLC’s mineral reference collection to evaluate, test, and optimize the various aspects of the method. Topics include sample preparation methods, spectral collection time, adjustment of instrument operation conditions, post-processing, evaluation of multiple search algorithms, and initial interpretations of the results from real-world soil samples.
Morphological Differences in Grass Fiber Pulps Used in Papermaking
Walter J. Rantanen — SGS – IPS Testing
The use of papermaking fiber of different species from the Poaceae (Gramineae) family has been utilized for centuries. Cereal straws have been a very common source for use due to the easy availability. Large amounts of certain grass species growing in a local area have also been historically utilized. This was true especially before the large-scale pulping of wood fiber. The expanded availability of certain wood pulp fiber decreased the use of grass pulps, initially. With the “green” movement, some types have increased, especially bamboo, bagasse, and wheat straw. Many grass pulps are very similar in appearance under the microscope. There may be only subtle differences or overlap of features, which can hinder correct identification. Some morphological features will be presented to assist in their identification.
The Investigation of the Lost 9/11 Ground Zero American Flag
Nicholas Petraco
In the early afternoon of Sept. 11, 2001, amid the burning rubble and chaos of the World Trade Center attack, New York City firefighters removed a small American flag from a private yacht docked near the World Trade Center and raised it at Ground Zero. The flag became a symbolic image of American patriotism. The photograph of the firefighters raising the flag above the rubble was taken by Thomas E. Franklin of The Bergen Record. His photo has been compared by many to the iconic photo by Joe Rosenthal of the six Marines raising the U.S. flag on Mount Suribachi during the battle of Iwo Jima in World War II.
The 9/11 flag was then reportedly presented at a patriotic rally in Yankee Stadium and was signed by many dignitaries, and then it reportedly traveled around the world on a U.S. Navy aircraft carrier. In April 2002, New York City officials returned the flag to its owners, who discovered it was not the flag taken from their yacht. The whereabouts of the authentic 9/11 flag remained a mystery for nearly 12 years until it was reported missing on “Brad Meltzer’s Lost History” TV show on Oct. 14, 2014. A few days after the show aired, an anonymous former marine presented a small flag to a firefighter in Everett, WA, stating that this was the actual 9/11 flag. This prompted a yearlong investigation to determine the origin of this questionable flag. This talk recounts the events surrounding the acquisition, raising, disappearance, recovery, analysis, authentication, and installation of the lost 9/11 flag.
Collecting, Analyzing, and Enjoying Chemical and Alchemical Art
Skip Palenik — Microtrace LLC
The presenter has been interested in paintings depicting chemists and alchemists1 since admiring the black and white picture of an “alchemist in his laboratory,” which served as the front piece of the booklet of instructions accompanying his second chemistry set. As a young adult, I saw for the first time, a large color print of the painting from which that picture had been taken and could not believe how beautiful it was to behold for the first time, as the artist had intended, in terms of size and color. No wonder! It had originally been painted for the Hercules Powder Company’s calendar in 1937 by N.C. Wyeth.
This presentation will follow the author’s acquisition of certain paintings over time, beginning with the collection of prints, which grew into commissioned reproductions of admired works, and finally into the acquisition of signed original paintings, slowly and over the years, as funds permitted. The artworks to be shown will be accompanied by notes on the artists who painted them, some thoughts on the personal enjoyment of analyzing their pigments, media, and supports, as well as learning what they reveal by IR and X-ray imaging. Included is commentary on the surprises and creative inspiration that beautiful images provide while working in the laboratory to solve our clients’ problems.
1Paintings of microscopists and microchemists are much harder to come by, but that is another story.
Clay Staining
Andrew A. “Tony” Havics — pH2, LLC
The staining of clays to aid in identification has long been recognized as a useful microscopical technique. Perhaps the significant look was Faust’s Staining of Clay Minerals as a Rapid Means of Identification in Natural and Beneficiated Products in 1940. Staining can also be used to relate fundamental clay properties as cation exchange capacity, dry bond strength, casting rate, and even specific surface, using the methylene blue index (MBI). Over the years some mixed results have emerged. In yet another attempt to add to that knowledge, we evaluated benzidine, nitrobenzene with malachite green, and methylene blue. We evaluated a well-crystallized and a poorly crystallized kaolin, Ca-montmorillonite, Na-montmorillonite, synthetic mica-montmorillonite, hectorite (with CaCO3), polygorskite attapulgite, ferruginous smectite, illite, sepiolite, rectorite, nontronite, and vermiculite.
The Perfect Shots: Crafting a Photomicrographic Setup and Image List for an Atlas of Charred Particles
Sebastian Sparenga — McCrone Research Institute
When presenting scientific research, one sometimes has the difficult task of showing the results of their work in the most comprehensive manner. As a microscopist, one of the best ways to do this is with one or more photomicrographs. This presentation will discuss a setup necessary to obtain the most beneficial images using a wide variety of light microscope illumination conditions, including plane polarized light, top/reflected light, crossed polars, slightly uncrossed polars, crossed polars and a Red I compensator, and various combined conditions, including how to display them for publication. This work is in preparation of a current research project involving unreacted, partially burned, and fully burned particles associated with low explosives and their microscopic residues. This project was supported by Award No. NIJ-2019-DU-BX-0047, awarded by the National Institute of Justice, Office of Justice Programs, U.S. Department of Justice.
View Presentations for Tuesday, June 13