Chemical Profiling of Trace Odours for Forensic Identification: A Review

@#Trace odour is one of the trace material evidence that has significant value in forensic analysis. The recovery of relevant trace odour components from clothing has the potential to be a form of trace evidence that can be used to assess the likelihood of a contact between individuals in sexual and violent cases. They have the same potential as other trace evidence and can narrow down the suspect in the investigation. Studies conducted previously related to trace odour have succeeded in proving that this trace odour is unique, has its signature profile and can distinguish it from other sources such as fingerprints and DNA. This review highlights these trace odours and their persistence after being transferred, which contribute to a complete picture of the dynamics and potential application in the forensic reconstruction process. The literature was sourced from electronic databases such as Scopus, PubMed, Springer Link, Wiley On¬line Library and Science Direct. Keywords such “odour”, “trace odour”, “scent”, “volatile organic compound”, “forensic identification” were utilised. Further studies on various forms of trace odour are needed to strengthen their evidential values and be admissible to the court.

Recycling Potential of Natural Waste Products in the Development of Fingerprint Powders for Forensic Application

@#Introduction: The most common method to emerge latent fingermarks on non-porous surfaces is powdering by applying commercial fingerprint powders. However, the chemical composition of the powder is often toxic and poses health hazards to humans. This study was endeavoured to explore the effectiveness and potential use of natural resources for the enhancement of latent fingermarks. Methods: Eggshells and clamshells were prepared in fine powder form, and latent fingermarks were developed using each powder. Five non-porous substrates were selected for fingermarks deposition; glass, aluminium can, plastic book cover, painted wood, and compact disc. Results: Both natural powders have successfully developed high-quality finger marks with high clarity of ridge characteristics in comparison to commercial fingerprint powder (positive control) and untreated fingermark (negative control) on most of the tested surfaces tested. The sebaceous fingermarks have shown the best quality fingermarks when developed with both powders. In the ageing study, it was found that most non-porous substrates bearing latent fingermarks exposed to the destructive conditions can be successfully visualised in the early period of exposure. Conclusion: Eggshell and clamshell powders are as effective as commercial white powder but preferrable to be applied because of the low cost, abundant and non-hazardous.

Exposure Risk of Household Insecticide: Identification of the Knowledge, Attitude and Practice Levels among Kuantan Population, Pahang

@#Introduction: Dengue is a mosquito-borne flu-like illness which massively caused Malaysian morbidity and mortality. The prevalent of cases influenced by high humidity climate and urbanization which enhances the mosquito breeding. Thus, the utilization of household insecticide became a necessity among the urban community especially in the Kuantan city, Pahang. The insecticide is made of type 1 pyrethroids chemicals that are recognized to be safe. However, there were reported insecticide intoxication cases that suggested insufficient studies on insecticide usage and its exposure effects. Hence, the study aimed to assess the community’s knowledge, attitude and practice (KAP) level upon household insecticide and its associated factors among Kuantan’s public. Method: A cross-sectional survey was conducted among 199 respondents via a self-administered questionnaire concerning sociodemographic and KAP’s domain data was distributed and collected. Results: Most respondents had adequate KAP scores. Statistical analysis confirmed that marital status group (p = 0.047) affected knowledge singles and married person had higher knowledge score. There were significant association between females with levels of knowledge (p = 0.003) and attitude (p = 0.024). A strong positive correlation between knowledge and attitude (r = + 0.800, p = 0.010), between knowledge and practice (r = + 0.760, p = 0.010), and a good positive correlation between attitude and practice (r = + 0.740, p = 0.010). Conclusion: The finding of Kuantan public’ KAP data can be used as a reference to formulate effective health promotion intervention to reduce the insecticide exposure risk among wider public community.

Green Chemistry Synthesis of Nanostructured Zinc Oxide Powder Using Azadirachta indica Extract for Latent Fingermark Development

@#Introduction: Application of nano-engineered fingerprint dusting powders has been a recent trend to achieve latent fingermark development with superior ridge clarity. As such, efforts have been made to utilise natural resources to increase the sustainability of these emerging nano-engineered powders. Lithium-doped zinc oxide, primarily used as white pigments, have been previously applied to latent fingermarks with success. In the current study, nanostructured zinc oxide, synthesised using neem extract as the reducing agent, was evaluated for fingermark development on non-porous surfaces. Methods: The reduction of zinc nitrate hexahydrate was facilitated by neem extract, prepared by boiling neem leaves in distilled water. The thick yellow paste recovered was calcined in the furnace to produce a light yellow powder. Physicochemical composition of the powder was determined using microscopic and spectroscopic instruments. The effectiveness of the powder was tested on natural fingermark deposited on several non-porous surfaces. Results: Nanostructured zinc oxide with particle size ranging in between 1 to 3 µm consisting of highly aggregated spherical particle with less than 100 nm dimensions were synthesised. Developed fingermarks revealed excellent ridge details and contrast on dark coloured surfaces. Studying the fingermark closely under scanning electron microscope displayed selective distribution of particle on the ridges of the fingermark residue and very minimal deposition on the fingermark valleys. Conclusion: Nanostructured zinc oxide fabricated using green chemistry approach can be applied for the development of fingermark. Nevertheless, future works can be undertaken to enhance particle dispersity and to confer strong photoluminescence to the zinc oxide nanoparticles.

Morphological and Compositional Changes Exhibited by Rice Husk When Subjected to Synergistic Thermochemical Treatments

@#Introduction: Rice husk has portrayed great potential in becoming a sustainable biomass source in producing silica, cellulose and carbon materials, which garnered widespread interest among researchers. The objective of the current study is to determine the morphological and compositional changes in rice husk due to the synergistic effects of thermochemical treatment. Methods: Washed and dried rice husk was blended into a fine powder and then subjected to step-wise heat treatment and acid digestion to produce white ash. The intermittent products, as well as the original rice husk and the final ash product, were characterised using analytical instruments to document the morphological and chemical composition changes. Results: This report highlights the production of pure rice husk ash using a step-wise treatment using a combination of thermochemical treatment and carbonisation. The results showed that a partial breakdown of the lignocellulose components was achieved using directed thermal treatment at low temperature. The ionic impurities were leached out in subsequent heated acid treatment. Thereafter, the carbonaceous organic matter was completely converted to carbon during the carbonisation of the sample and the remaining carbon residue was removed during calcination. High purity ash contained agglomerated and nanostructured silica in the dimensions of 20 to 50 nm in the amorphous form. Conclusion: The step-wise treatment allowed systematic removal of each compound while maintaining the amorphous mineral phase of silica and avoiding carbon fixation. Understanding the effect of each treatment offers insight to produce purer silica from rice husk.

Species Determination and Discrimination of Animal Blood: A Multi-Analytical Spectroscopic-Chemometrics Approach in Forensic Science

@#Introduction: Non-destructive analysis of biological evidence has been paramount importance in the forensic investigation since it is an effective tool in establishing a standard that could be employed to differentiate ensuing destructive tests of bio-fluids upon sample division between the plaintiff and defendant. Species identification of bloodstain found at the crime scene is very crucial in routine forensic work as this can assist the initial investigation by incorporating or excluding stain that is not human and to identify its origin if animal blood is involved. Methods: In this research, identification and discrimination of various blood species collected from seven domestic animals namely chicken, cow, deer, duck, fish, goat, and pig were investigated using non-destructive analytical techniques; ATRFTIR and visible spectroscopy coupled with principal component analysis and linear discriminant analysis (PCALDA) for classification purposes. Results: ATR-FTIR FTIR spectroscopic study demonstrated a higher rate of successful classification (≥ 90%) as compared to visible spectroscopic technique. Conclusion: ATR-FTIR spectroscopy has been an ideal, robust, and suitable tool for determining the blood species of domestic animals. The predictive model from PCA-LDA analysis can be utilised to produce higher classification rate for species determination from blood traces.