Pusat Pengajian Sains Perubatan - Monograf

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3d sex prediction model in malays using lower second molar
(2026-02)
Hong, Tan Zong
Sex prediction models play a crucial role in forensic science, particularly in disaster victim identification (DVI), by reducing the potential identification pool by approximately half. Sex is also a fundamental component of the biological profile, as it forms the basis for estimating other parameters such as age and stature. To date, no studies have investigated sex prediction using occlusal traits—specifically intercuspal distance (ICD), interpit distance (IPD), and total length of the central groove (TLCG)—within the Northeastern Malay population of Malaysia. Therefore, this study aimed to evaluate the relationship between occlusal traits of the lower second molar and sex among the northeastern Malay population. Measurements of ICD, IPD, and TLCG were obtained indirectly from 3D dental casts of 200 Malay individuals (100 males and 100 females) using 3-Matics software. An independent t-test was conducted to assess sexual dimorphism between sexes. Sex prediction models were developed using four machine learning approaches: Logistic Regression (LR), Support Vector Machine (SVM), Random Forest (RF), and Decision Tree (DT). The results demonstrated that mean values of ICD, IPD, and TLCG were generally higher in males than in females, except for the ML–MB distance. Among the models tested, LR achieved the best performance, with an area under the curve value (AUC) of 0.70. Stepwise LR analysis identified ML–MB (p = 0.008), MB–DB (p = 0.014), and MB–DL (p = 0.007) as significant predictors of sex. Two of the variables studied were statistically significantly larger in males than females. The percentages of sexual dimorphism ranged from 0.3-7.4%. The highest sex prediction model was LR and yielded fair classification (classification accuracy = 0.63, AUC value = 0.70). Other models yielded poor classification.
A study on acid violence and corrosive acid damage pattern to textiles
(2025)
Razak, Nurul Fatil Atikah
Acid attack cases are one of the forms of crime that have serious physical and psychological effects on the victim and leave important forensic evidence at the scene. This study was conducted to assess the effects of corrosive agents on various types of textiles and identify the presence of corrosive agent anions through the color spot test, in addition to analyzing the trend of acid attack cases in Malaysia through the analysis of online news archives. The design of this study involved news content analysis to identify patterns of acid spill cases in Malaysia, laboratory experiments to assess the effects of corrosive agents on textiles such as cotton, viscose, and polyester, and color spot tests or chemical tests for the detection of corrosive agent anions. News analysis also showed an increase and certain patterns in acid attack cases in Malaysia. Observations showed that corrosive agents produce significant physical changes in textiles, including color changes, fiber expansion, and disintegration of fabric structure, depending on the type of textile and the duration of exposure. The color spot test also showed the ability to detect the presence of certain anions clearly and quickly. Overall, this study proves that the analysis of corrosive agent effects on textiles and the detection of anions through the color spot test have significant value in assisting forensic investigations, which involves hurt or even death to victims
Adsorptive removal of MN(II) and FE(II) from aqueous solutions using raw lime, lemon and pomelo peels
(2026-01)
Rajan, Darshan Namana
The issue of heavy metal contamination in the Kelantan River basin and its tributaries, where it’s documented that Fe and Mn frequently exceed Malaysian National Water Quality Standards. To address this issue, this thesis investigates the adsorptive removal of Fe(II) and Mn(II) from aqueous solutions using unmodified peels of three common citrus fruits in Malaysia—key lime (Citrus aurantiifolia), lemon (Citrus lemon) and pomelo (Citrus maxima) as low‑cost biosorbents. The fruit peels were characterized by Fourier Transform Infrared Spectroscopy (FTIR) to identify surface functional groups, and initially analysed by Atomic Absorption Spectroscopy (AAS) to confirm the absence of initial Fe and Mn contamination. Following that, batch adsorption experiments were performed in synthetic Fe and Mn solutions under systematically varied pH (3–6), adsorbent dosage (0.2–0.8 g), contact time (10–80 min) and reusability over four adsorption–desorption cycles. Adsorption performance was quantified by AAS using multi‑point calibration curves with excellent linearity (R² ≈ 0.999 for both Fe and Mn), enabling accurate determination of post‑adsorption metal concentrations and percentage removal. FTIR spectra of all peels showed hydroxyl, carboxyl/carbonyl and ether/alcohol bands, with intensity changes after metal uptake implicating these groups involved in surface binding interactions with Fe(II) and Mn(II). Optimal pH was 5, with 0.2 g dosage and short contact times optimal across peels. Key lime achieved the highest Mn(II) removal (91.75%, retaining 76.95% after four cycles), followed by lemon (85.75%) and pomelo (77.25%), while Fe(II) removal was lower (lemon: 43.23% max; key lime: 31.45%; pomelo lower), confirming Mn(II) selectivity. Overall, the findings demonstrate that unmodified citrus peels—particularly key lime—are effective, low‑cost and sustainable biosorbents for Mn removal and moderately effective for Fe, offering a practical route for agricultural waste and a promising supplementary treatment option for metal‑contaminated waters, although further modification and broader metal testing are recommended to enhance Fe adsorption and extend applicability.
Application of atr-ftir spectroscopy and chemometric techniques for the characterization of animal fiber-based commercial brushes
(2026-02)
Salimi, Mohamad Amirul Hakim Mohd
when precise differentiation of fibers is required. Animal-fiber brushes are frequently employed in industrial and artistic settings, although it can be challenging to distinguish between different types due to their striking similarities. The purpose of this study is to use spectroscopic analysis and chemometric approaches to distinguish and examined brushes product made from different animal fibers samples such as Horse (A), goat (B), pony (C), squirrel (D), weasel (E), wolf (F), and pig (G). All samples were examined using Attenuated Total Reflection–Fourier Transform Infrared (ATR-FTIR) spectroscopy in the range of 4000 cm⁻¹ to 600 cm⁻¹. The infrared spectra were first compared visually to identify common functional groups related to protein-based fibers. However, strong overlap between spectra made it difficult to clearly distinguish the samples using visual analysis alone. Therefore, Principle Component Analysis(PCA) was performed on the spectral data for better discriminatory power. The fingerprint region ranging from 1500 cm⁻¹ to 600 cm⁻¹ was selected for analysis since it contains valuable information regarding the fibers. PCA nearly discriminated the brush samples based on the types of animal fibers. The total variation of the data was explained by the first three principal components, which accounted for 90.33%. They were PC1, PC2, and PC3, which accounted for 63.96%, 16.77%, and 9.6% pf variance, respectively. This study demonstrates that the integration of ATR-FTIR spectroscopy with PCA is a straightforward, rapid, and non-destructive technique for distinguishing animal-fiber brushes, hence facilitating applications in forensic analysis related to wildlife crime, material identification, and quality control.
Association of cariogenic food frequency intake, physical activity level with body mass index among undergraduate students in USMKK
(2026)
Azman, Ahmad Haikal
Frequent consumption of cariogenic foods and low levels of physical activity are associated with energy imbalance and unhealthy weight status among university students. However, evidence regarding the relationships between cariogenic food consumption, physical activity level and Body Mass Index among undergraduate students at Universiti Sains Malaysia Health Campus remains limited. This study aimed to determine cariogenic food consumption, physical activity level and Body Mass Index status, and to examine the associations between these variables. A cross-sectional study was conducted among 209 undergraduate students from the School of Medical Sciences, School of Dental Sciences and School of Health Sciences. Cariogenic food consumption was assessed using the Malay Cariogenic Food Frequency Questionnaire, while physical activity level was measured using the Malay Version of the Global Physical Activity Questionnaire. Body weight and height were measured to determine Body Mass Index. Data were analysed using IBM SPSS Statistics version 27. Descriptive statistics were used to summarise the study variables, while Chi-square tests were used to examine associations at a significance level of p < 0.05. The findings showed that 72.2% of respondents had moderate cariogenic food consumption and 27.8% had low consumption, with no respondents classified in the high-consumption category. Regarding physical activity, 49.8% had a high level, 38.8% had a moderate level and 11.5% had a low level. For Body Mass Index status, 45.5% had normal weight, 23.4% were obese, 18.2% were underweight and 12.9% were overweight. Overall, 36.3% were overweight or obese. No significant association was found between cariogenic food consumption and Body Mass Index status, χ²(3) = 1.640, p = 0.650, or between physical activity level and Body Mass Index status, χ²(6) = 1.526, p = 0.958. Although no significant associations were identified, the high proportion of overweight and obesity indicates the need to strengthen healthy eating, physical activity and weight-management programmes among university students.
Atr-ftir spectroscopic analysis for forensic differentiation of cooking oils
(2026-02)
Naderajan, Shamini
The accurate classification of cooking oils is important for quality control, and forensic investigations such as food fraud and adulteration. In this study, attenuated total reflectance–Fourier transform infrared (ATR-FTIR) spectroscopy combined with chemometric analysis namely PCA and LDA was used to discriminate various type of cooking oils based on their spectral profiles. The type cooking oil samples analysed in this study were (i) black seed oil, (ii) canola + sunflower oil, (iii) canola oil, (iv) castor oil, (v) coconut oil, (vi) corn oil, (vii) olive oil, (viii) perilla seed oil, (ix) palm oil, (x) rice bran oil, (xi) sesame oil and (xii) sunflower oil. The spectrum of ATR-FTIR in both fingerprint region (1800–600 cm⁻¹) and the C–H stretching region (3050–2800 cm⁻¹) was not reliable due to overlapping spectral features in both spectral regions which made it harder to differentiate different types of cooking oil. Therefore, PCA which is an unsupervised method was performed where clear clustering of the cooking oils can be seen in the scatterplot of PC2 versus PC3 especially for black seed oil, perilla oil coconut oil and palm oil in the second region. The chemometric analysis was followed by a supervised method namely, LDA where the principal component (PC) score obtained from PCA for its respective region. Overall classification accuracy for fingerprint region was only 50.8% where misclassification of samples was observed in canola, sunflower, and corn oils due to having similar chemical structure. In contrast, the second region has very high accuracy for classification of cooking with 90.0% accuracy. Sunflower oil, canola oil and the blend of sunflower and canola oil was later re-classified as vegetable oil to improve the accuracy of classification. This has greatly improved overall accuracy to 91.7%. However, sesame oil remained as the most misclassified sample due to having very similar chemical structures to other type of cooking oils. The findings in this study demonstrate that ATR-FTIR spectroscopy coupled with PCA-LDA is a rapid, non-destructive method to discriminate various fresh cooking oils
Chemical characterisation of fresh and used cooking oils by ATR-FTIR spectroscopy
(2026-02)
Ting, Camey Ho Ting
Cooking oils may undergo chemical degradation when subjected to high temperatures during frying and with the addition of food matrices, leading to oxidation, hydrolysis and polymerisation reactions. The repeated reuse of frying oil, particularly in informal food sectors, causes chemical degradation and the formation of potentially hazardous compounds, emphasising the need for a spectroscopic approach to monitor oil quality and ensure food safety. The aim of this work was to chemically characterise and distinguish between fresh cooking oil, cooked oil without food matrices, and oils fried with different food matrices utilising attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy combined with chemometric analyses. In this study, fresh cooking oil were used to fry the various food matrices, including plant-based and animal-based diets, and the collected cooking oils were analysed using ATR-FTIR spectroscopy. Subsequently, principal component analysis (PCA) and linear discriminant analysis (LDA) were used to evaluate the classification capabilities based on the ATR-FTIR profiles. Through observation, the ATR-FTIR spectral profiles of the cooking oil samples showed distinctive absorption bands associated with triglycerides. Visual inspection and direct spectral comparison revealed negligible variations between cooking oils fried with various food matrices with no significant spectral differences. PCA successfully differentiated between fresh and cooked oils, demonstrating observable chemical changes caused by heating. Although PCA alone was insufficient to effectively distinguish between oils fried with and without food matrices, a PCA-LDA had enhanced discrimination capabilities with 98.0 % classification accuracy. To conclude, this study demonstrates the effectiveness of ATR-FTIR spectroscopy combined with chemometrics in determining heat-induced chemical changes in cooking oils and discriminating the cooking oils based on frying circumstances. The findings emphasised this method's potential for assessing oil quality and monitoring food safety level.
Chinese gangsterism among Malaysians: A qualitative approach
(2026-02)
Rames, Samuel Peter
This study explores the lived experiences of Chinese gangsters in Malaysia, focusing in Kuantan, Pahang, highlighting the reasons to why most people remain in gangs for a long period before deciding to quit gangsterism. Perspectives from ex-gangsters and police officers were obtained and analysed. The research methodology employed a phenomenological approach (semi-structural interview) to delve into the essence of these individuals’ experiences. Thematic and summative analysis of interview transcripts using NVivo 15 software revealed six main themes and six emerged themes under three main sections: 1) Factors to join gangs, 2) Reasons to remain in gangs, and 3) Knowledge on gangsterism. This study is done due to the lack of studies on Chinese gangsterism. It provides valuable insights into the lived experiences of Chinese gangsterism in Malaysia. This study highlights the unspoken world of Chinese gangsterism in Kuantan and also provides a whole different ideology on gangsterism. Unlike usual gangsterism cases and ideology given by gangsters all around the world, the Chinese gangsters in Kuantan have a complete opposite perspective on gangsterism and gang activities. The ex-gangsters and police officers had provided their insights and perspectives regarding this matter.
Comparative analysis of burial degradation of textile fibres in different soil moisture contents using atr-ftir spectroscopy
(2026-02)
Min, Chan Hui
Textile materials are commonly encountered as evidence in forensic investigations involving assault, homicide, sexual offences, and clandestine burials. However, limited research has focused on the short-term burial of textiles for estimating time since burial. The effects of different soil moisture contents on textile degradation also remain largely unexplored. This study investigated the comparative burial degradation of textile fibres under different soil moisture contents over a six-week burial period. Three textile types were examined, including natural fibres (cotton and silk) and a synthetic fibre (polyester). The textiles were buried in soils with the moisture contents were adjusted to 0%, 20%, 40%, and 60% water holding capacity (WHC). Samples were collected weekly and analysed using stereomicroscopy and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy to evaluate morphological changes and chemical alterations, respectively. Multivariate statistical techniques, including principal component analysis-linear discriminant analysis (PCA-LDA) and partial least squares regression-discriminant analysis (PLSR-DA) were applied to the spectral data to assess degradation trends and to model to model the estimation of time since burial. Morphological observations revealed that cotton exhibited the most pronounced degradation, followed by silk and polyester showed the greater and comparable resistance to burial conditions. ATR-FTIR analysis combined with PCA showed clear separation of samples according to their types with classifications rate of 99.8%. The PLSR models further showed that burial time could be predicted with reasonable accuracy with R2 values ranging from 0.93 to 0.98 based on the spectral data.
Comparative analysis of DNA extraction methods in the recovery of human DNA from earphones
(2026-02)
Ying, Leeanne Yong Luo
Personal devices like earphones can be significant in forensic investigations as a source of DNA, especially when biological evidence is lacking. Although several studies have demonstrated successful DNA extraction and profiling from earphone samples, the most suitable DNA extraction method remains undescribed. DNA extraction is one of the most crucial steps in DNA analysis. Therefore, this study aimed to compare three different extraction methods, including silica-based commercial kit, Chelex-100 and phenol-chloroform method, to identify the most efficient method in recovering human DNA from earphones. A total of 66 samples were analysed, with 22 samples extracted using each method. DNA yield and purity were assessed using DeNovix DS-11, followed by PCR amplification using hGH autosomal primer and mitochondrial primer to assess DNA integrity. 3 samples from each method were further subjected to Real-time qPCR for quantification of amplifiable DNA. The findings demonstrated that phenol-chloroform yielded the highest and fluctuating DNA concentrations, as measured by DeNovix DS-11; however, the lowest yield when measured by qPCR, indicating contamination and overestimation by the spectrophotometer. The silica-based method yielded the lowest concentrations in spectrophotometry measurement, and moderate concentrations in the qPCR, but was the only method with successful autosomal amplification. The Chelex method displayed the second-highest concentration, but the highest concentration in qPCR. Chelex also demonstrated the greatest amplification success rate using mtDNA. These findings indicate that no single extraction method can excel in both quantity and quality parameters simultaneously. However, the Chelex method was found to recover DNA that performed better than the other methods, in terms of yield and amplifiability
Comparative efficiency between different swab types for touch dna recovery from different surfaces
(2025)
Sirajudin, Alya Amirah
Deoxyribonucleic acid (DNA) analysis is a fundamental tool in forensic science, enabling human identification in criminal investigations. In cases where visible biological evidence such as blood or saliva is absent, touch DNA has emerged as an alternative source of genetic material. However, touch DNA presents significant analytical challenges due to its low quantity, variable transfer, and inconsistent recovery from different surfaces. This study focused on evaluating the efficiency of different swab types and surface materials in the recovery and amplification of touch DNA to improve its forensic applicability. Touch DNA samples were deposited through natural handling to simulate realistic forensic scenarios. Three swab types (cotton, dacron, and nylon-flocked) were used to collect samples from glass, ceramic, and plastic surfaces. DNA extraction was performed using a silica-based method optimized for low-template samples. Quantitative polymerase chain reaction (qPCR) analysis revealed low and variable DNA yields across all swab–surface combinations, with no statistically significant differences observed between swab types. To assess amplification feasibility, polymerase chain reaction (PCR) targeting mitochondrial DNA (mtDNA) regions of 176 bp and 310 bp was conducted. Agarose gel electrophoresis demonstrated a markedly higher amplification success for the 176 bp mtDNA fragment compared to the 310 bp fragment across all conditions. Surface type did not show a consistent effect on amplification outcomes. These findings indicate that amplicon size is a critical determinant of successful touch DNA analysis. The use of short mtDNA targets enhances amplification reliability, supporting the forensic utility of touch DNA in cases involving low-template biological evidence.
Comparative study of DNA extraction methods for recovering degraded DNA from chewing gum under varied environmental condition
(2026-02)
Rohaizi, Rose Anessa Sofea
Chewing gum is a potential source of forensic DNA due to its prolonged contact with saliva and frequent recovery at crime scenes. However, DNA deposited on chewing gum is often exposed to environmental factors that may compromise its integrity. This study aimed to evaluate the recovery and amplification of degraded DNA from chewing gum samples subjected to varied environmental conditions. Chewing gum samples were collected from human participants and exposed to different environmental conditions over multiple time intervals to simulate realistic forensic scenarios. DNA extraction was performed using the Chelex® 100 resin method. The recovered DNA was assessed using agarose gel electrophoresis, spectrophotometric analysis, conventional polymerase chain reaction (PCR), and quantitative polymerase chain reaction (qPCR) to evaluate DNA presence, degradation patterns, and amplification success. Agarose gel electrophoresis revealed varying degrees of DNA degradation across samples, with increased fragmentation observed in samples exposed for longer durations. Conventional PCR targeting short human-specific amplicons demonstrated successful amplification in selected samples, indicating the presence of amplifiable DNA despite environmental exposure. qPCR analysis further confirmed the detection of human DNA in multiple samples, although amplification efficiency varied depending on exposure conditions and duration. The results indicate that chewing gum can retain detectable and amplifiable human DNA following environmental exposure, although DNA quality is influenced by time and environmental factors. This study provides empirical data on DNA persistence and degradation in chewing gum samples and supports the forensic relevance of chewing gum as a source of trace DNA. The findings contribute to the limited body of forensic literature on unconventional biological substrates and offer insight into the challenges of DNA recovery from environmentally exposed salivary evidence.
Cyberstalking among Gen Z in Malaysia: A qualitative study on perceptions, experiences, and reporting behaviours
(2026-02)
Alam, Nur Aafreen Mohammed Parwez
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Detection of 9-BP deletion in coii/trnalys intergenic region of mitochondrial DNA among Melanau ethnic group
(2026-02)
Hasanuddin, Nur Syaqirah Ahmad
Mitochondria are essential organelles in organism responsible for cellular energy production, which is necessary for metabolic reactions. It has its own genetic material called mitochondrial DNA (mtDNA) and has interesting features such as maternal inheritance, high mutation rate, high copy number and lack of recombination. MtDNA has been applied in forensic identification to solve forensic cases and is also used in population genetics studies. One of the mtDNA polymorphisms used in population genetics studies is located between cytochrome c oxidase II (COII) and lysine tRNA (tRNALys) genes, consisting of the two copies of a 9-bp tandem repeat sequence (CCCCCTCTA). Deletion of on copy in this tandem is used as a characteristic for mtDNA haplogroup B. This study aimed to detect the presence of the 9-bp deletion in the COII/tRNALys intergenic region of mitochondrial DNA among Melanau individuals through PCR amplification and agarose gel electrophoresis. Genomic DNA was extracted from the whole blood samples and assessed for quality and quantity to ensure sufficient DNA for downstream analysis. PCR amplification of the target region was performed using primers 8215F and 8385R. The findings show that 24 Melanau individuals (20%) had 9-bp deletion, and this distribution is supported by the previous studies that 9-bp deletion is frequently observed in the population of mainland southeastern Asia, Island southeast Asia and Southwest Asian.
Detection of drug traces in post-developed fingermarks using ATR-FTIR spectroscopy
(2026-02)
Perkash, Kavisha T Siva
Fingermarks are commonly employed for human identification in forensic investigations; however, they can also serve as chemical reservoirs, retaining residues of foreign chemicals such as narcotics. Fingermarks are frequently subjected to development techniques before to examination in genuine forensic cases, but the impact of these activities on later chemical detection has received scant attention. This work assesses the feasibility of Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy as a non-destructive analytical method for detecting drug residues in post-developed fingermarks. Sebaceous fingermarks contaminated with paracetamol and caffeine were deposited on selected non-porous substrates namely glass, plastic, and aluminum foil surfaces. Fingermarks were developed using magnetic and non-magnetic fingerprint powders for visualisation and then analysed using ATRFTIR spectroscopy. A limit of detection (LOD) investigation was carried out to establish the lowest detectable levels of both medications, and several sampling procedures were investigated to optimise drug recovery from contaminated fingermarks. A persistence study was also conducted to determine the detectability of drug residues in contaminated fingermarks after one week of deposition. The findings showed that typical ATR-FTIR absorption bands of paracetamol and caffeine could still be successfully detected and recognised in post-developed fingermarks with minimal interference from fingerprint powders or lifting materials. Furthermore, drug residues were detectable during 7 days of intervals, demonstrating reasonable persistence within the fingermark matrix. Overall, this study demonstrates the potential of ATR-FTIR spectroscopy to preserve ridge detail while also providing chemical information from post-developed drug-contaminated fingermarks. The findings justify the incorporation of ATR-FTIR analysis into standard forensic fingermark examination, which increases the evidential value of fingermarks by allowing for simultaneous biometric and chemical intelligence.
Detection of porcine derived in sweet jelly product through PCR amplification of the mitochondrial DNA ND5 gene
(2026-01)
Jaelan, Putri Junaidah
Sweet jelly products that are available in the market are predominantly made from either porcine or bovine gelatine derived. The risk of adulteration and mislabeling of gelatine origin has become a concern among consumers due to religious beliefs, dietary and health issues. Therefore, this study aims to detect the porcine derived ingredients in sweet jelly products through PCR amplification of the mtDNA ND5 gene species-specific primer. A total of 20 samples of sweet jelly products obtained from various sources were extracted using the CTAB-phenol-chloroform method and analysed using conventional PCR targeting the mtDNA ND5 gene of porcine mtDNA. In this study, the DNA extracted from fresh pork raw meat was used as a positive control for porcine DNA. The result shows the mtDNA ND5 primer was highly specific to the porcine target species and has a limit of detection of 1 pg of DNA. PCR amplification of the mtDNA ND5 species-specific primer against all sweet jelly products showed that only one sample S2, was positive for porcine DNA. Interestingly, one sample S12, clearly declared to contain pig gelatine in its product, was negative for PCR amplification using the mtDNA ND5 primer. This could be caused by exposure to high temperature during the manufacturing and the enzymatic processes, resulting in extremely degraded DNA. In conclusion, the in-house designed primer mtDNA ND5 gene was proven as a porcine species-specific primer and can be used for the detection of porcine-derived from sweet jelly products.
Determination of heavy metals in powder and cream blushers from local cosmetic brands using atomic absorption spectroscopy (AAS)
(2026-01)
Fazlin, Qistina Sara
Heavy metals have been widely used in the manufacture of cosmetic products, including blusher, which mainly serve as colorants. However, higher concentrations of heavy metals could cause adverse health effects to the consumer such as kidney failure, liver dysfunction and skin irritation especially for long-term exposure. This study aims to analyse the concentration of heavy metals, lead (Pb), cadmium (Cd) and chromium (Cr) in the blusher samples which are powder-based blusher and cream-based blusher among the local brands products. Hence, two different types of formulations from three different local brands were randomly selected from local market. Each sample undergoes homogenisation and wet acid digestion process as the sample preparation procedure. The blusher samples were analysed using atomic absorption spectrophotometer (AAS) in order to determine the concentration of heavy metals in the sample. Due to inconsistency differences in concentration of heavy metals among powder and cream blusher, it prevents a clear comparison of the metal content. The data and results obtained from the study were compared to the established regulatory limit of heavy metals in cosmetic products as outlined by the Association of Southeast Asian Nations (ASEAN) and Malaysian National Pharmaceutical Regulatory Agency (NPRA). As the result, samples A, B, C, Y and Z displayed Pb concentration that above permissible limit, (Pb ≤10 ppm). Cd levels above the allowable limit (Cd ≤1 ppm) were observed among samples C, X and Z. Higher concentrations of Cr were observed in sample A, B, X and Z (Cr is banned). However, the authorities should closely monitor the manufacture of local cosmetic products as exceeding the standard permissible limit of heavy metals could cause adverse health effects to the consumers and may be charged under the Sale of Drugs Act 1952.
Determination of selected heavy metal concentrations in a blusher cosmetic of different colour shades
(2026-01)
Aziz, Nurul Fatin Fakhira Abdul
Blusher, as one of the cosmetic products widely used by consumers, playing a pivotal role in potential health risks. This study endeavours to delve into the concentration of heavy metals in blusher cosmetics of various colour intensity, and to evaluate whether colour intensity influences heavy metal content. A study was carried out on one brand of blush pellet consisted of 6 different tones of colour intensities which purchased from online platform with the highest sold numbers. The blush samples were categorised by its colour intensities starting from very low (SA), low (SB), medium low (SC), medium high (SD), high (SE), and very high (SF) colour intensity. The concentrations of selected heavy metals namely lead (Pb), cadmium (Cd), and chromium (Cr) were determined by using Atomic Absorption Spectroscopy (AAS) following acid digestion. The concentration of selected heavy metals varied according to the following trend: Cr (17.321 to 21.998 mg/kg) > Pb (12.329 to 17.820 mg/kg) > Cd (4.838 to 6.011 mg/kg), except for sample A (SA) as it follows trend: Pb (27.250 mg/kg) > Cr (23.430 mg/kg) > Cd (5.795 mg/kg). The results showed that Pb and Cd exceeded permissible limits set by ASEAN Cosmetic Directive (ACD) and National Pharmaceutical Regulatory Agency (NPRA) of Malaysia in selected samples, while Cr exhibited comparatively higher concentrations despite the absence of a specified regulatory limit. Furthermore, statistical analyses like Spearman’s rank correlation, Kruskal-Wallis, and Mann-Whitney tests were employed to evaluate relationship and differences in metal concentrations among samples. The statistical results indicated variability in heavy metal concentrations across blush samples, with no consistent association was observed between colour intensity and heavy metal concentration, thus, the heavy metals contamination in blush cosmetics varies among products and is not solely influenced by colour intensity. The results of this study can be a basis for future studies on cosmetic manufacturing quality control and regulatory monitoring process.
Determining the fly and maggot population based on different types of animal meat
(2026-02)
Yie, Olivia Ong Jian
Necrophagous insects play a crucial role in forensic entomology, particularly in the estimation of post-mortem interval (PMI). Specifically, necrophagous flies have been the focus of relevant studies as they are the earliest colonizer of decomposing carcasses and cadavers. This study focuses on investigating the differences between the necrophagous fly species associated with different types of animal meat, which are pork, lamb, and beef. The experiment was conducted twice during rainy and non-rainy seasons to simultaneously examine the influence of environmental factors, including rainfall, ambient temperature, and humidity. A key finding was the distinct feeding preferences exhibited by Megaselia Scalaris (Diptera: Phoridae) and Sarcophaga sp. (Diptera: Sarcophagidae) exclusively towards beef, while Chrysomya Megacephala were observed to feed on all types of animal meats studied, and Chrysomya Rufifacies feeds on both pork and beef. Additionally, environmental factors played a key role in influencing the decomposition rate and the insect activity, which leads to delayed decomposition and the oviposition of necrophagous flies. However, the findings of this study were limited to identifying the difference in feeding preferences among necrophagous flies, while the underlying causes were yet to be determined.
Development of latent fingermarks at extremely low temperature
(2026-02)
En, Loo Yee
Fingermarks are a crucial form of forensic evidence due to their persistence and individuality. However, their stability can be affected by environmental exposure and substrate characteristics. Criminals may attempt to conceal evidence by subjecting it to extreme conditions such as freezing, making the recovery of usable fingermarks a significant forensic challenge due to residue degradation and condensation effects. This study investigated the development of latent fingermarks on various substrates, including food (apple and orange), five types of plastics (HDPE, PET, polypropylene, polystyrene and LDPE), metal and glass after exposure to −20°C in the freezer for one week. The study was conducted in two phases; a preliminary experiment to assess surface changes and identify effective development methods for fresh sebaceous fingermarks, and a main experiment to evaluate development performance after freezing. Eight development techniques were examined: non-magnetic powder, magnetic powder, SPR, Sudan Black, Amido Black, Crystal Violet, Oil Red O and ninhydrin. Sudan Black, Oil Red O and magnetic powder consistently showed higher effectiveness in the preliminary phase for most tested substrates. Results from the main experiment indicated that latent fingermarks could still be developed after being frozen at −20°C for one week. However, a general reduction in quality and ridge detail was observed. Fingermark quality was influenced by substrate type and development technique. Non-porous substrates such as plastic, metal and glass retained ridge detail longer than food substrates, which exhibited faster degradation due to higher moisture content. These findings provide valuable insight into the effects of extreme cold exposure on fingermark development and support the improvement of protocols for latent fingermark visualisation and preservation in cold or frozen environments.

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