An investigation into the effect of surveillance drones on textile evidence at crime scenes

With increasing numbers of Police forces using drones for crime scene surveillance, the effect of the drones on trace evidence present needs evaluation. In this investigation the effect of flying a quadcopter drone at different heights over a controlled scene and taking off at different distances from the scene were measured. Yarn was placed on a range of floor surfaces and the number lost or moved from their original position was recorded.It was possible to estimate "safe" distances above and take off distance from the bath mat (2. m and 1. m respectively), and carpet tile (3. m and 1. m) which were the roughest surfaces. The maximum distances tested of 5. m above and 2. m from was not far enough to prevent significant disturbance with the other floor surfaces. This report illustrates the importance of considering the impact of new technologies into a forensic workflow on established forensic evidence prior to implementation

Encouraging innovation

The second annual report of the Government Chief Scientific Adviser (GCSA), Sir Mark Walport, looks at the power of forensic science and its many applications. The report draws on evidence provided by experts in several fields. It covers the use of forensic analysis within the criminal justice system through to the prevention, deterrence and detection of fraudulent products and services

Perceptions of a program approach to virtual laboratory provision for analytical and bioanalytical sciences

When teaching chemistry and biosciences courses to undergraduate and postgraduate students, laboratory experience is a crucial requirement for skills development. Due to COVID-19 related closure of laboratories it became critical to replace that experience with virtual delivery. Through carefully designed learning experiences it is possible for students to gain skills such as experimental design, problem solving, record keeping and data analysis. Here we present a coordinated approach to the design of laboratory classes for a cross discipline postgraduate program. Virtual laboratory classes, using freely available web-based simulators, were run in a synchronous manner with pre lab briefing and post lab data analysis sessions. The laboratory scripts were developed using a command prompt design: [Do][Explore][Act] framework, which is intended to provide students with a guided approach to using the simulator while in a remote setting. The intended outcome was to develop student’s record keeping and understanding of the scientific principles of the instrumentation through practical experimentation. Student experience of the virtual laboratory provision was surveyed via a mix method approach, with an 81% response rate. Satisfaction with the virtual labs was high (68%), with students agreeing the laboratories contained the appropriate balance of challenge and support. The command prompts were thought to be a very useful way to structure a lab script (77% agreement) and many suggested this approach should be kept for future laboratory use. Students self-identified the main skills learnt as being laboratory bookkeeping, analyzing data, problem solving and use of equipment

Influence of the initial chemical conditions on the rational design of silica particles

The influence of the water content in the initial composition on the size of silica particles produced using the Stöber process is well known. We have shown that there are three morphological regimes defined by compositional boundaries. At low water levels (below stoichiometric ratio of water:tetraethoxysilane), very high surface area and aggregated structures are formed; at high water content (>40 wt%) similar structures are also seen. Between these two boundary conditions, discrete particles are formed whose size are dictated by the water content. Within the compositional regime that enables the classical Stöber silica, the structural evolution shows a more rapid attainment of final particle size than the rate of formation of silica supporting the monomer addition hypothesis. The clearer understanding of the role of the initial composition on the output of this synthesis method will be of considerable use for the establishment of reliable reproducible silica production for future industrial adoption

Quantitative analysis of methamphetamine in hair of children removed from clandestine laboratories - evidence of passive exposure?

In New Zealand many children have been removed from clandestine laboratories following Police intervention. In the last few years it has become standard procedure that these children have hair samples taken and these samples are submitted to the laboratory for analysis. There are various mechanisms for the incorporation of drugs into hair. The hair follicle has a rich blood supply, so any drug that may be circulating in the blood can be incorporated into the growing hair. Another mechanism is via external contamination, such as spilling a drug on the hair or through exposure to fumes or vapours. Hair samples were analysed for methamphetamine and amphetamine. From the 52 cases analysed 38 (73%) were positive for methamphetamine (>0.1 ng/mg) and amphetamine was detected in 34 of these cases. In no case was amphetamine detected without methamphetamine. The hair washes (prior to extraction) were also analysed (quantified in 30 of the positive cases) and only 3 had a wash to hair ratio of >0.1 (all were <0.5), which may be indicative of a low level of external contamination. This low level of evidence of external contamination suggests that the children are exposed to methamphetamine and are incorporating it into the hair through the blood stream

Analytical perspectives and endocrine implications of androstenedione administration to young women

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Quantitative analysis of hair samples for 1-benzylpiperazine (BZP) using high-performance liquid chromatography triple quadrupole mass spectrometry (LC-MS/MS) detection.

Benzylpiperazine (BZP) is an amphetamine-type stimulant, which was legally available in New Zealand and widely used in “Party Pills” until reclassification as a Class C drug in April 2008. BZP was included as part of a multi-analyte method developed for hair screening using high-performance liquid chromatography triple quadrupole mass spectrometry (LC-MS/MS). A 20-mg sample of hair is extracted and partially purified using mixed-mode solid-phase extraction cartridges prior to analysis by LC-MS/MS. The method was developed as a broad screen for drugs of abuse (including amphetamines, opiates, and benzodiazepines), with only the BZP results being presented here. The assay was validated and found to be linear over the range of 0.085 to 8.65 ng/mg with correlation coefficient of r 2 ≥ 0.99. Blank hair samples spiked with BZP at 0.22 and 2.16 ng/mg gave intra- and inter-day precision coefficients of variation of ≤10% (n = 6 per day, 3 days) at both levels and calculated extraction efficiencies of 78% and 91%, respectively. The results from the samples submitted to the laboratory for BZP analysis showed 11% were positive (n = 126). The mean BZP level was 3.9 ng/mg (range, 0.4–33 ng/mg; the result was extrapolated when above the calibration). These data are the first available showing the levels expected from users of BZP

Deaths in Rotorua's geothermal hot pools: hydrogen sulphide poisoning.

In late 2007 and early 2008 two gentlemen were found dead in, or near to, enclosed hot pools fed with Rotorua's geothermal waters. Amidst much publicity the Coroner has ruled that the deaths were related to hydrogen sulphide poisoning. Following post mortem examinations, blood and urine samples were frozen and sent to the Toxicology Unit of ESR. These were then stored frozen until analysis. Hydrogen sulphide (H(2)S) is a potentially deadly gas at elevated levels, but is rapidly eliminated from the body and is unstable post mortem. Thiosulphate is a marker for the exposure to H(2)S, and as it is stable post mortem the samples were analysed to determine the thiosulphate levels present. The urine thiosulphate levels detected were above those seen in the urine samples measured from the only previous study of people exposed to the Rotorua thermal area and the blood levels were similar to literature values from fatalities exposed in workplaces such as sewage treatment plants

Qualitative drug analysis of hair extracts by comprehensive two-dimensional gas chromatographytime-of-flight mass spectrometry.

A technique using comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry (GC × GC/TOFMS) is applied to a qualitative analysis of three sample extracts from hair suspected of containing various drug compounds. The samples were also subjected to a quantitative target analysis for codeine, morphine, 6-monoacetylmorphine (6-MAM), amphetamine, methamphetamine, methylenedioxyamphetamine (MDA), methylenedioxymethylamphetamine (MDMA), methadone, and benzylpiperazine (BZP) by liquid chromatography-tandem mass spectrometry (LC-MS/MS). GC × GC/TOFMS provided a non-specific procedure that identified various drugs, metabolites, and impurities not included in the target analysis. They included cocaine, diazepam, and methaqualone (quaalude). Comprehensive GC × GC separation was achieved using twin-stage cryo-modulation to focus eluant from a DB-5ms (5% phenyl) to a BPX50 (50% phenyl) GC column. The TOF mass spectrometer provided unit mass resolution in the mass range m/z 5–1000 and rapid spectral acquisition (≤500 spectra/s). Clean mass spectra of the individual components were obtained using mass spectral deconvolution software. The ‘unknown’ components were identified by comparison with mass spectra stored in a library database