18 research outputs found
Rapid on-site identification of hazardous organic compounds at fire scenes using person-portable gas chromatography-mass spectrometry (GC-MS). Part 2: Water sampling and analysis
Building and factory fires pose a great risk to human and environmental health, due to the release of hazardous by-products of combustion. These hazardous compounds can dissipate into the environment through fire water run-off, and the impact can be immediate or chronic. Current laboratory-based methods do not report hazardous compounds released from a fire scene at the time and location of the event. Reporting of results is often delayed due to the complexities and logistics of laboratory-based sampling and analysis. These delays pose a risk to the health and wellbeing of the environment and exposed community. Recent developments in person-portable instrumentation have the potential to provide rapid analysis of samples in the field. A portable gas chromatograph-mass spectrometer (GC-MS) was evaluated for the on-site analysis of water samples for the identification of hazardous organic compounds at fire scenes. The portable GC-MS was capable of detecting and identifying a range of volatile and semi-volatile organic compounds in fire water run-off, and can be used in conjunction with conventional laboratory analysis methods for a comprehensive understanding of hazardous organics released at fire scenes. Deployment of this portable instrumentation provides first responders with a rapid, on-site screening tool to appropriately manage the run-off water from firefighting activities. This ensures that environmental and human health is proactively protected
Rapid on-site identification of hazardous organic compounds at fire scenes using person-portable gas chromatography-mass spectrometry (GC-MS). Part 1: Air sampling and analysis
Recent advancements in person-portable instrumentation have resulted in the potential to provide contemporaneous results through rapid in-field analyses. These technologies can be utilised in emergency response scenarios to aid first responders in appropriate site risk assessment and management. Large metropolitan fires can pose great risk to human and environmental health due to the rapid release of hazardous compounds into the atmosphere. Understanding the release of these hazardous organics is critical in understanding their associated risks. Person-portable gas chromatography-mass spectrometry (GC-MS) was evaluated for its potential to provide rapid on-site analysis for real-time monitoring of hazardous organic compounds at fire scenes. Air sampling and analysis methods were developed for scenes of this nature. Controlled field testing demonstrated that the portable GC-MS was able to provide preliminary analytical results on the volatile organic compounds present in air samples collected from both active and extinguished fires. In-field results were confirmed using conventional laboratory-based air sampling and analysis procedures. The deployment of portable instrumentation could provide first responders with a rapid on-site assessment tool for the appropriate management of scenes, thereby ensuring environmental and human health is proactively protected and scientifically informed decisions are made for the provision of timely advice to stakeholders
Portable gas chromatography–mass spectrometry method for the in‑feld screening of organic pollutants in soil and water at pollution incidents
Environmental pollution incidents generate an emergency response from regulatory agencies to ensure that the impact on the environment is minimised. Knowing what pollutants are present provides important intelligence to assist in determining how to respond to the incident. However, responders are limited in their in-feld capabilities to identify the pollutants present. This research has developed an in-feld, qualitative analytical approach to detect and identify organic pollutants that are commonly detected by regulatory environmental laboratories. A rapid, in-feld extraction method was used for water and soil matrices. A coiled microextraction (CME) device was utilised for the introduction of the extracted samples into a portable gas chromatography–mass spectrometry (GC–MS) for analysis. The total combined extraction and analysis time was approximately 6.5 min per sample. Results demonstrated that the in-feld extraction and analysis methods can screen for ffty-nine target organic contaminants, including polyaromatic hydrocarbons, monoaromatic hydrocarbons, phenols, phthalates, organophosphorus pesticides, and organochlorine pesticides. The method was also capable of tentatively identifying unknown compounds using library searches, signifcantly expanding the scope of the methods for the provision of intelligence at pollution incidents of an unknown nature, although a laboratory-based method was able to provide more information due to the higher sensitivity achievable. The methods were evaluated using authentic casework samples and were found to be ft-for-purpose for providing rapid in-feld intelligence at pollution incidents. The fact that the in-feld methods target the same compounds as the laboratory-based methods provides the added beneft that the in-feld results can assist in sample triaging upon submission to the laboratory for quantitation and confrmatory analysis
Complexity of scientific evidence in environmental forensic investigations
Purpose – Environmental forensic investigations rely on the collection, analysis and interpretation of evidence from an environmental scene to assist in identifying the party responsible for the introduction of exogenous material. These investigations also try to elucidate if the environment and/or human health have been affected. The paper aims to discuss these issues.
Design/methodology/approach – Environmental forensic investigations are considered a sub-category of the forensic sciences. The potential scientific evidence is subjected to the same rigour as for other forensic science disciplines, including quality control, accreditation, chain of custody and evidence integrity. The manner in which evidence is analysed and interpreted is also similar. Even though strong similarities can be drawn between environmental forensic investigations and the general forensic sciences, some important differences need to be understood. Findings – Environmental forensic investigations can be more complex than they first appear and identifying,
analysing and interpreting scientific evidence is not always straightforward. It is crucial in the comprehension of the complexities of the environmental forensic discipline to understand the intricacies of the investigations,
including the limited sample numbers, complex matrices, wide range of exogenous materials encountered, often large size of the scene, changes to the scene and, above all, the potential for degradation or transformation of evidence. In addition, scientific evidence is frequently used to gather intelligence rather than to provide knowledge that can be brought forward to determine guilt or innocence of an accused party. Originality/value – This paper explores the complexities of the discipline and discusses the difficulties that are encountered during environmental investigations
The evolution of environmental forensics : from laboratory to field analysis
Environmental forensics aims to provide investigations into pollution incidents to establish the source of the pollution and any environmental or human health impacts. Casework is strongly reliant on field investigations and subsequent laboratory-based analysis for confirmation of pollutants present. Current advances in field-portable instrumentation are shaping the environmental forensics discipline and provide an evolutionary change in the operational capabilities of environmental investigators. The implementation of field-portable equipment into the environ-mental investigative framework provides great advances and opportunities, but also needs to be performed with caution to ensure reliable results. Combining the use of field-portable instrumentation with small mobile forensic laboratories provides fora rapid and flexible emergency response capability that can also be applied to non-emergency scenarios to aid pollution mapping and tracking, including source determination. The field-portable equipment can be used in the controlled environment of the mobile laboratory, but can also be used in-situ where required. Although field-portable equipment is not likely to replace laboratory-based analysis methods in the near future, it does provide important intelligence to the field investigator, resulting in a more targeted and detailed investigation of the scene. This allows fora more focussed laboratory-based investigation and will result in more rapid and appropriate investigations into environmental incidents. Ultimately, this will ensure a better protection of the environment and human health
[In Press] Evaluation of digital panoramic images to support off-site bloodstain pattern analysis
Crime scene photography plays a fundamental role in forensic investigations. Its primary purpose is the recording of the entire crime scene, both the context and specific details, for later recollection, analysis and presentation. Bloodstain pattern analysis (BPA) relies extensively on the recording of context and detail. This study evaluated the use of panoramic imaging for the recording of impact patterns at crime scenes to support the off-site determination of area of origin (AO). This evaluation used a commercially available hardware system that consisted of a robotized, tripod-mounted platform, interfaced with a digital camera, to provide an automated panoramic image capture process. Software was subsequently used to construct a digital panorama. Bloodstain pattern analysis software was then used for the off-site determination of AO from the panoramic image. The results of this research demonstrated that the developed method can be employed to effectively capture a panoramic image of an impact pattern with sufficient detail for accurate AO determination. The approach can enable crime scene officers to record impact patterns without extensive training on BPA or the recording of blood spatter. The approach also enables BPA experts to digitally analyse spatter information from a single image as opposed to evaluating multiple photograph
Using sterol profiles for fingerprinting biodiesel and matching biodiesel spill samples to a source
An increase in the production of biodiesel has been accompanied by a rise in the occurrence of biodiesel spills. To determine the source of a spill, fatty acid methyl ester fingerprinting is generally used. However, in the experience of these authors, this approach was of limited use for matching biodiesel residues back to the source material. The present work demonstrates sterol profiling for matching spill samples to a source. Sterol profiling was found to be a better approach for this than fatty acid methyl ester profiling, with the added benefit that sterol analysis could determine the feedstock used in the production of biodiesels
Effects of weathering on sterol, fatty acid methyl ester (FAME), and hydrocarbon profiles of biodiesel and biodiesel/diesel blends
The weathering of biodiesel and biodiesel/diesel blends was investigated to determine the changes in the profiles of fatty acid methyl esters (FAMEs), sterols, and hydrocarbons. Sterols were more persistent than FAMEs and are better candidates for identifying biodiesels in environmental media and for determining the source of a biodiesel spill. The changes in FAME and sterol profiles over time are discussed. In biodiesel blends, accelerated weathering was observed for pyrene, fluoranthene, and their alkyl homologues compared to diesel. FAME and sterol analysis should be performed in addition to hydrocarbon profiling to distinguish between a weathered diesel and a weathered biodiesel/diesel blend
Pyrolysis-GC-MS analysis of crude and heavy fuel oil asphaltenes for application in oil fingerprinting
A Pyrolysis – Gas Chromatography – Mass Spectrometry (Py-GC-MS) method was developed for the analysis and profiling of crude and heavy fuel oil asphaltenes, for application in oil fingerprinting. Asphaltenes were precipitated from ten geographically different oils using n-pentane, and analysed by Py-GC-MS. Alkane profiles and sulphur/aromatic profiles were used to compare the oils, and to correctly differentiate oils from different geographical regions. Py-GC-MS could not differentiate a weathered oil sample and a fresh oil sample from the same source. The results of this study support the findings from a previously developed FTIR method for asphaltene profiling
An FTIR method for the analysis of crude and heavy fuel oil asphaltenes to assist in oil fingerprinting
A proof-of-concept spectroscopic method for crude and heavy fuel oil asphaltenes was developed to complement existing methods for source determination of oil spills. Current methods rely on the analysis of the volatile fraction of oils by Gas Chromatography (GC), whilst the non-volatile fraction, including asphaltenes, is discarded. By discarding the non-volatile fraction, important oil fingerprinting information is potentially lost. Ten oil samples representing various geographical regions were used in this study. The asphaltene fraction was precipitated from the oils using excess n-pentane, and analysed by Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR). Based on visual interpretation of FTIR spectra along with peak height ratio comparisons, all ten oil samples could be differentiated from one another. Furthermore, ATR-FTIR was not able to differentiate a weathered crude oil sample from its source sample, demonstrating significant potential for the application of asphaltenes in oil fingerprinting