Fire Debris Analysis Eric Stauffer, Julia A. Dolan, Reta Newman
2008, 2007
eBook
The study of fire debris analysis is vital to the function of all fire investigations, and, as such, this book is an essential resource for fire investigators. The present methods of analysis include ...the use of gas chromatography and gas chromatography-mass spectrometry, techniques which are well established and used by crime laboratories throughout the world. However, despite their universality, this is the first comprehensive resource that addresses their application to fire debris analysis. This book covers topics such as the physics and chemistry of fire and liquid fuels, the interpretation of data obtained from fire debris, and the future of the subject. Its cutting-edge material and experienced author team distinguishes this book as a quality reference that should be on the shelves of all crime laboratories. The book serves as a comprehensive guide to the science of fire debris analysis; presents both basic and advanced concepts in an easily readable, logical sequence; and includes a full-color insert with figures that illustrate key concepts discussed in the text.
Introduction Globally, overdose deaths increased near the beginning of the COVID-19 pandemic, which created availability and access barriers to addiction and social services. Especially in times of a ...crisis like a pandemic, local exposures, service availability and access, and system responses have major influence on people who use drugs. For policy makers to be effective, an understanding at the local level is needed. Methods This retrospective epidemiologic study from 2019 through 2021 compares immediate and 20-months changes in overdose deaths from the pandemic start to 16 months before its arrival in Pinellas County, FL We examine toxicologic death records of 1,701 overdoses to identify relations with interdiction, and service delivery. Results There was an immediate 49% increase (95% CI 23–82%, p < 0.0001) in overdose deaths in the first month following the first COVID deaths. Immediate increases were found for deaths involving alcohol (171%), heroin (108%), fentanyl (78%), amphetamines (55%), and cocaine (45%). Overdose deaths remained 27% higher (CI 4–55%, p = 0.015) than before the pandemic through 2021.Abrupt service reductions occurred when the pandemic began: in-clinic methadone treatment dropped by two-thirds, counseling by 38%, opioid seizures by 29%, and drug arrests by 56%. Emergency transport for overdose and naloxone distributions increased at the pandemic onset (12%, 93%, respectively) and remained higher through 2021 (15%, 377%,). Regression results indicate that lower drug seizures predicted higher overdoses, and increased 911 transports predicted higher overdoses. The proportion of excess overdose deaths to excess non-COVID deaths after the pandemic relative to the year before was 0.28 in Pinellas County, larger than 75% of other US counties. Conclusions Service and interdiction interruptions likely contributed to overdose death increases during the pandemic. Relaxing restrictions on medical treatment for opioid addiction and public health interventions could have immediate and long-lasting effects when a major disruption, such as a pandemic, occurs. County level data dashboards comprised of overdose toxicology, and interdiction and service data, can help explain changes in overdose deaths. As a next step in predicting which policies and practices will best reduce local overdoses, we propose using simulation modeling with agent-based models to examine complex interacting systems.
Synthetic opioids such as fentanyl account for over 71,000 of the approximately 107,000 overdose deaths reported in the United States in 2021. Fentanyl remains the fourth most identified drug by ...state and local forensic laboratories, and the second most identified drug by federal laboratories. The unambiguous identification of fentanyl-related substances (FRS) is challenging due to the absence or low abundance of a molecular ion in a typical gas chromatography-mass spectrometry (GC-MS) analysis and due to a low number of fragment ions that are similar among the many potential isomers of FRS. This study describes the utility of a previously reported gas chromatography-infrared (GC-IR) library for the identification of FRS within a blind, interlaboratory study (ILS) involving seven forensic laboratories. Twenty FRS reference materials, including those with isomer pairs in the library, were selected based on either their presence in the NIST library and/or some similarity of the mass spectra information produced. The ILS participants were requested to use the Florida International University (FIU) GC-MS and GC-IR libraries supplied by FIU to search for matches to their unknown spectra generated from in-house GC-MS and GC-IR analysis. The laboratories reported improvement in the positive identification of unknown FRS from ~75% using GC-MS alone to 100% correct identification using GC-IR analysis. One laboratory participant used solid phase IR analysis, which produced spectra incompatible with the vapor phase GC-IR library to generate a good comparison spectrum. However, this improved when searched against a solid phase IR library.
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The analytical process for identifying ignitable liquids is based on fundamental chemical properties; however, the current interpretation of these properties as chromatographic data ...relies on subjective pattern recognition techniques. The subjectivity of these pattern recognition techniques increases with the presence of complex matrix contribution. To make the fire debris interpretation process more standardized and objective, a novel method is proposed for analyzing fire debris Gas Chromatography-Mass Spectrometry (GC–MS) data using quantitative measures of chromatographic features of interest. These features are represented by peak height ratios observed in the Total Ion Chromatograph and Extracted Ion Profiles.
Chromatographic features of interest in 150 gasoline samples were evaluated and 64 chromatographic peak height ratios were selected for study. Statistical analysis was conducted to determine the variation observed for each of these ratios in the gasoline samples and to determine the frequency of these features in negative matrix samples. This information was evaluated to determine relative significance, as represented by the assigned points for each of these features. When summed and used as plot values, these cumulative scores graphically display the separation of gasoline samples from negative matrix samples using this methodology. The scores were used to create a sufficiency graph, which is a graphical display detailing the totality of data supporting a potential gasoline identification. The sufficiency graph also identifies the “gray” area where analysts are more likely to form differing opinions.
The methodologies introduced are a step toward a documentation process that ensures greater transparency in fire debris examinations and comparisons. The methods generate a quantitative sufficiency graph for consistent data interpretation and documentation.
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•A headspace concentration method was evaluated with simulated fire debris.•Sensitivity analysis identified important instrument settings.•Capillary temperature did not affect ...performance, so design can be simplified.•Water content of the debris did not affect performance.
Dynamic vapor microextraction (DVME) is a potential method for the extraction and concentration of ignitable liquid (IL) residue in fire debris. This low flow rate, purge-and-trap headspace concentration method collects IL vapors onto a chilled adsorbent capillary and recovers them by elution with acetone. As an emerging method for fire debris analysis, the sensitivity of DVME performance to instrument settings has yet to be established and, additionally, the effect of variability inherent in authentic fire debris (e.g., water content) has not yet been explored. In this work, we quantitatively evaluate the effect of 11 factors via a sensitivity analysis with simulated fire debris. The factors studied included six controllable instrument settings and five reflecting debris characteristics. We quantified performance by covariance mapping between gas chromatography – mass spectrometry (GC–MS) retention time – ion abundance matrices for the recovered eluates and corresponding reference samples. Six factors were found to be significant. IL volume, IL weathering, and debris quantity significantly affected the recovered eluates, whereas water content did not. As related to recovering IL residue from simulated fire debris, recommended instrument settings include a higher oven temperature, longer equilibration time, larger volume of extracted headspace (collection volume), and a lower inlet flow rate. Together with the covariance mapping metric, the fractional factorial design successfully addressed questions about the effect of instrument factors, debris factors, and their interactions with an efficient number of experiments.
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•GC-IR analysis of FRS distinguish between positional isomers of FRS compounds.•MS spectra alone may not always differentiate positional isomers of FRS.•New libraries of GC–MS and ...GC-IR spectra of 212 FRS are made available.•LODs for fentanyl using GC-IR range between 0.10 and 0.19 mg/mL.
Forensic laboratories routinely use gas chromatography mass spectrometry (GC–MS) in the identification of controlled substances using both retention time and electron impact ionization (EI) mass spectra. Certain drugs such as positional isomers of some fentanyl related substances (FRS) can produce indistinguishable EI mass spectra but may be differentiated using retention time. The core structure of fentanyl consists of an amide group, a piperidine ring, an aniline ring, and an N-alkyl chain, each providing opportunities for points of substitution that create FRS and corresponding positional isomers. For this study, the analysis by GC coupled to a vapor-phase infrared spectroscopy detector (GC-IR) was used as a complementary technique to GC–MS for the identification of positional isomers of FRS. The result is a novel fentanyl library consisting of 212 different FRS reference compounds. A collaboration among three different laboratories yielded correct identifications of twenty blind samples when searched against the GC-IR FRS library created at Florida International University (FIU). The expected limits of detection for fentanyl using GC-IR range between 0.10 and 0.19 mg/mL, depending on the sample introduction (injector) method and other instrumental parameters. The newly created GC-IR library and its GC–MS counterpart of 212 FRS are shared in the supplementary materials for future use by researchers and practitioners.
Abstract
The opioid epidemic in the USA has been associated with an increasing mortality rate in large part due to the emergence and proliferation of synthetic opioids over the last 15 years. ...Fentanyl and its analogs have played a large part in these statistics due to their potency and toxicity. Fluorofuranylfentanyl (FFF) is a fentanyl analog that emerged in the USA in 2018 and was associated with numerous adverse events and deaths. During this study, a liquid chromatography tandem mass spectrometry workflow was developed to accurately identify the isomer of FFF present (ortho- vs. meta- vs. para-) in medicolegal death investigation cases from Pinellas County, Florida. FFF was quantified in central and peripheral blood samples collected at autopsy. In addition, the metabolism of FFF was studied using liquid chromatography quadrupole time-of-flight mass spectrometry. para-FFF was quantitatively confirmed in 29 postmortem cases; no other isomer of FFF was detected. Central blood concentrations ranged between 0.66 and 73 ng/mL (mean = 11 ± 14 ng/mL, median = 10 ng/mL) and peripheral blood concentrations ranged between 0.53 and 23 ng/mL (mean = 5.7 ± 6.4 ng/mL, median = 2.7 ng/mL). A comparison of central to peripheral blood concentrations was evaluated to determine the possibility of postmortem redistribution. The metabolism of ortho-FFF was studied and found to undergo metabolic processes similar to fentanyl, producing ortho-fluorofuranyl-norfentanyl, fluoro-4-anilino-N-phenethylpiperidine, and hydroxylated species. The results of this study demonstrate the toxicity of FFF and its implication in medicolegal death investigations. Laboratories must remain aware of new or re-emerging fentanyl analogs, as they pose significant risks to public health and public safety.
Dynamic vapor microextraction (DVME) is a headspace concentration method that can be used to collect ignitable liquid (IL) from fire debris onto chilled adsorbent capillaries. Unlike passive ...headspace concentration onto activated carbon strips (ACSs) that must be eluted with a toxic solvent (carbon disulfide), DVME employs a relatively benign solvent (acetone) to recover the adsorbed IL residue, and each headspace collection is monitored for breakthrough. Here, for the first time, we extend DVME to casework containers while exploring a realistic range of oven temperatures and collection volumes. We investigated metal cans sealed with friction lids (container 1), metal cans sealed within polymer bags (container 2), and glass jars sealed with two-piece lids (container 3). Without additional containment, container 1 was found to leak so excessively that flow through the capillary was unreliable. Therefore, for containers 2 and 3 only, we determined the total number of target compounds collected from 50% weathered gasoline for oven temperatures from 54 °C to 96 °C and collection volumes from 47 standard cubic centimeters (scc) to 90 scc. Only high-volatility species with retention times (tR)< n-decane on a non-polar column were recovered from polymer bags, whereas headspace concentration from glass jars led to the recovery of target compounds across the entire volatility range. DVME at 90 °C from 2-mL containers showed that the presence of polymer bag material leads to IL vapor losses, particularly for low-volatility species with tR> n-decane. DVME was strongly influenced by the casework container, whereas oven temperature and collection volume had a minor influence for the IL samples explored here.
•Dynamic vapor microextraction (DVME) is a low flow headspace concentration method.•DVME cannot be implemented with metal cans with friction lids due to leaks.•DVME recovered more target compounds from glass jars than polymer evidence bags.•Polymer bag material led to vapor loss, particularly for low-volatility species.
