Forensic Science Laboratory Research Articles

Studies On The Statistical Analysis And Impact Of Seasonal Temperature And Relative Humidity Variation On The Development Of A Flesh Fly Sarcophagadux(Thomson 1869)(Diptera Sarcophagidae)

Background: The fleshfly Sarcophaga dux (Diptera;Sarcophagidae) is found in Indian Sub continent is of limited forensic significance as its poorly known larval development relationship with temperature and relative humidity. Objective: The objective of this study was to determine the effect of the temperature and relative humidity in the larval development of this fly in two seasons, Summer and Rain, so that the results of this study may enabling the forensic use of this fly in the estimation of Post Mortem Interval(PMI). Material and Method: The present study was carried out in the outer premises of the Regional Forensic Science Laboratory Building, Jagdalpur, Bastardist,Chhattishgarh, India. The fresh meat of male goat was used for rearing of larvae. The effect of temperature and relative humidity on the larval developmental time of this fly in two seasons, Rainy and Summer were studied in normal condition. Statistical analysis of variance was performed and standard significance level of P<0.05 was taken as standard. Results: The results of this study shown that in Rainy season it was completed in 264 h (11 days) when the average temperature ranged from 21.8°C to 24.5°C and the average humidity ranged from 79.5% to 95.5% where as in Summer it was completed in 528 hrs (22 days), when the temperature ranged from 26.5°C to 35.1°C and the humidity ranged from 34% to 67.5%. The P value was found to be P<<.05 in Temperature variation; andP<<0.05 in Humidity variation in different stages(1st instar larvae, 2nd instar larvae, 3rd instar larvae, Prepupae, Pupae and Adult). Conclusion: In the present study we have found that fluctuating temperature and relative humidity of outer condition in two seasons, Rainy and Summer effect the life cycle duration of the fly from the larvi position up to adult eclosion and statistical analysis has proved it to significant rejecting null hypothesis. This data can be further used in the estimation of Post Mortem Interval (PMI) in Homicide and Suspicious cases of both human and wild life poaching death cases.

The transfer of spermatozoa onto children’s underwear during normal domestic laundering activities

In cases of sexual assaults involving children, biological evidence such as semen is often found on clothes rather than on intimate swabs. Two cases involving young girls were submitted to one of the AFSP BFF forensic science laboratories instigating further research into the background levels of semen on children’s underwear after being laundered, without sexual acts occurring. This study considered the potential for background levels of semen in the washing machine and the levels of semen transferred with varying laundry storage and washing arrangements. The results concur with previous studies that low levels of spermatozoa can transfer during washing; however, this study demonstrated that background levels of semen can be present on children’s clothing during domestic laundering activities which include male underwear when there are sexually active males within the household. Further, that semen can persist in the washing machine even after three washes. This study has produced data which will assist forensic scientists to evaluate cases of child abuse in a domestic setting.

The ‘soft’ sides of ISO17025

ABSTRACT Where accredited, the vast majority of forensic science laboratories, globally, are accredited to the ISO Standard ISO/IEC17025:2017 (ISO17025). The standard consists of diverse sections including Resource requirements and Process requirements which are afforded much attention. In our view, given significantly less attention are General and Structural requirements which address important issues that are critical, although often neglected, in the quality landscape, such as Impartiality, Confidentiality, Integrity, Culture and Improper influence. We highlight their importance in this article under the heading ‘soft’ clauses and suggest some preventive measures to be taken, as neglecting these aspects could be disastrous in many respects.

Use of innovative sample dryer for effective sample drying in forensic investigations: An experimental study

Back groundThe sample collection and preservation before transportation to a Forensic Science Laboratory in a medicolegal case in India is a crucial step in establishing a link between accused, victim, crime scene and the weapon. This paper discusses pioneering advancement in health technology—a state-of-the-art sample dryer developed to preserve biological samples during Forensic investigations. This unique design has been officially registered with the design office in India as a copy right. Aims and ObjectivesThe primary goal of the sample dryer is to augment the preservation of biological evidence by removing moisture content through air drying before packaging, sealing and its transportation to a Forensic Science Laboratory. Material and MethodsThe process of air drying of biological samples by variety of experiments conducted in sample’s dryer designed for the purpose which employs a range of air movement techniques including horizontal, vertical, and circular laminar flows to swiftly extract moisture from the samples. The drying duration for each experimental sample was documented upon manual confirmation of complete drying. ResultsThe results were extraordinary, showcasing that the sample’s dryer reduced the drying time drastically by up to 27 times lesser in comparison to conventional methods for identical samples. The diverse airflow patterns generated by the sample dryer unequivocally demonstrated it’s utility in achieving superior sample preservation through efficient air drying. ConclusionGiven the exceptional outcomes observed in the experimental phase, the authors strongly advocate for the widespread adoption of this innovative sample’s dryer equipment to ensure effective air drying of biological samples and their efficient sample preservation to enable successful forensic analysis as expected.

An Extensive Analysis of Contemporary Studies Forensics Sciences in India

: Forensic science in India has evolved over 100 years, with the first official laboratory being the Calcutta Forensic Science Laboratory in Kolkata founded in 1952. Modernization has led to the establishment of numerous central, state, and regional forensic laboratories and advancements in technology such as DNA profiling, pathology, forensic toxicology, and forensic anthropology. As the need for forensic education in India increases, educational institutions and universities have started offering forensic science as a subject. India has collaborated with international forensic organizations to stay updated on global developments. Contemporary studies in forensic sciences are crucial for adapting to technological advancements, addressing emerging crimes, improving DNA analysis, promoting interdisciplinary approaches, and maintaining quality assurance and standards. Forensic science plays a significant role in the humanitarian efforts, including the identification of missing people and victims of mass disasters. Advanced imaging techniques are crucial in forensic investigations. Indian forensic science education is divided into undergraduate and postgraduate programs, offering bachelor's degrees and specialized courses in areas like forensic toxicology, DNA analysis, and digital forensics.

Operational Procedures of Forensic Science Laboratories and Protocols for Sample Collection

This research paper delves into the operational procedures employed within forensic science laboratories, with a specific focus on the protocols governing sample collection. Forensic science plays a crucial role in the criminal justice system, providing evidence and expert analysis to aid investigations and legal proceedings. Effective operational procedures and rigorous protocols for sample collection are essential to maintain the integrity and reliability of forensic evidence. Through an in-depth examination of existing literature, case studies, and expert insights, this paper aims to provide a comprehensive understanding of the methodologies and guidelines employed in forensic laboratories worldwide. Additionally, it explores the challenges faced by forensic scientists in sample collection and processing, along with recommendations for improving practices and enhancing the quality of forensic evidence.

Sensing of Gunshot Residue components from real sample using Fluorescence Resonance Energy Transfer

The present work represents a Fluorescence Resonance Energy Transfer (FRET) based sensing method for detecting Gunshot Residue (GSR) components. Two laser dyes Acf and RhB have been used as donor and acceptor respectively in the FRET pair. The real sample was collected after test firing in a forensic science laboratory. On the other hand, a standard GSR solution has been prepared in the laboratory. For the preparation of standard GSR solutions, we used the water solutions of the salts BaCl2, SbCl3, and Pb(NO3)2. The FRET efficiency was measured between Acf and RhB to sense the presence of GSR components (Pb+2, Ba+2, and Sb+3) in both real sample and standard solution by mixing the salts in aqueous solution. It has been observed that the FRET efficiency systematically decreases in the presence of GSR components. To amplify the FRET efficiency of the dye pair, inorganic clay dispersion (laponite) was used. The enhancement in FRET efficiency represents a better sensitivity of the proposed sensor. The current sensor is useful for the quantification of concentrations of the GSR components in a real sample.

InDEL instability in two different tumoral tissues and its forensic significance.

There may be cases where malignant tumor samples can be used for forensic DNA profiling studies. STRs are the first systems preferred in forensic science laboratories for identification purposes. However, genetic instability in tumoral tissues causes STR polymorphism to change, leading to erroneous results. On the other hand, insertion/deletion polymorphism (InDels) are used as genetic markers in forensic science, as they have features that make both STR and SNPs preferable. Although previous studies approved that STR instability is observed in many different tumors, there are only a few studies that have displayed the instability of InDels in tumoral tissues before. In this study, it was aimed to determine whether instability is observed in formalin-fixed paraffin-embedded breast and thyroid tumoral tissues at 36plex InDel Panel. A total of 47 cases, 26 of which were diagnosed as breast cancer and 21 as thyroid cancer, were included in the study. In 21 of 26 (80.76%) breast cancers mutational changes were observed, however only 6 of 21 (28.57%) thyroid carcinoma cases displayed instability.Moreover, in these six cases, mutations were detected at only 1 or 2 loci. The most common change in both tissues was loss of heterozygosity. These findings suggest that paraffin embedded tissues of thyroid tumor can be used in cases of forensic genetic identification, however paraffin embedded breast cancer tissues should be examined with care. In conclusion, low InDel mutation rates compared to STR instability, make InDel analysis from paraffin blocks suitable for forensic genetic identification. However, researchers should keep in mind that there may be differences between the profiles of the tumoral tissues taken as reference and the actual case. In addition, by incorporating additional markers such as SNPs and microhaplotypes with low mutation rates into the study alongside Indels, researchers can significantly enhance the discrimination power in identification processes.

The Sydney Declaration – An unique opportunity for Africa

The Sydney Declaration (SD) has the inherent virtue of shifting the focus from the tools used in forensic science to the fundamental characteristics of appropriate forensic practice analysis of a situation and all related trace data for the purpose of resolving a case. Though several differences might be observed between countries regarding the technologies used, the fundamental principle of forensic logical reasoning are universally applicable to all contexts and environments and not only restricted to sophisticated, well-resourced, established forensic science laboratories based in countries that offer adequate resources, strong networks and legal frameworks. In Africa, several countries lack resources to train practitioners and to develop forensic science institutes, laboratories and other relevant institutions. The SD can serve as departure point to attain appropriate forensic science outcomes. Upholding its sound guidance can help forensic science practitioners remain faithful to their science, acknowledge their limits, give expert opinions based solely on facts and scientific analysis and interpretation, whilst also enhancing communication with their stakeholders. As forensic science develops in Africa, the SD presents a timely opportunity for us to proceed with a common understanding and a solid foundation through which our field can grow.

Challenges in Viscera Analysis: Addressing Errors in Forensic Reporting and Their Medico-Legal Implications

Death is defined as the permanent and irreversible cessation of all biological functions that sustain life. In cases of unnatural death, such as poisoning, an inquiry is conducted by the police or magistrate under Indian law, followed by a post-mortem examination. Poisoning, particularly in suicides, is a common cause of unnatural deaths encountered during autopsies. The cause of death in such cases is confirmed only after receiving a chemical analysis report from the Forensic Science Laboratory (FSL). Viscera samples are sent for chemical analysis in suspicious death cases or when the cause of death is unclear after autopsy. Often, viscera reports return negative, making it difficult for forensic doctors to determine the exact cause of death, thereby delaying justice or, in some cases, weakening prosecution efforts. This article explores the reasons for errors in viscera reports and discusses their medico-legal implications.

Strategies for assessing the limit of detection in voltammetric methods: comparison and evaluation of approaches.

The realm of analytical chemistry continues to struggle with defining and evaluating the limit of detection in analytical methods in the sense that a multitude of definitions, criteria, caveats, and methods have been proposed, developed, and adopted across disciplines. The last decade has seen a surge in the growth of electrochemical methods and studies in the field of forensic science and forensic chemistry. While many disciplines within forensic science have established method validation guidelines, the historical and current lack of electrochemical methods within forensic laboratories throughout the United States has left a major gap in knowledge, inhibiting the adoption and utilization of electrochemistry, which may serve as a powerful tool in many subdisciplines of forensics. As such, this work begins this discussion by focusing first on the limit of detection (LOD), with application toward both qualitative and quantitative methods. Both inorganic (ferrocyanide and lead) and organic (diphenylamine, naltrexone, and acetaminophen) target analytes were analyzed via two common voltammetry methods: cyclic voltammetry and square-wave voltammetry. The LOD for each analyte was estimated and/or calculated following a variety of literature-described methods and compared. The accuracy and reliability of these LOD characteristics based on the experimental data is described herein along with suggestions and recommendations. This manuscript is intended to compare the resulting LOD values from various methods and provide a starting point for the incorporation of electrochemistry into the forensic science laboratory, beginning a focused discussion on the development of validation guidelines and parameters needed for the adoption of this technology in forensic laboratories in order to meet the standards required by the criminal justice system.

Barcode Inbuilt Inter-operable Criminal Justice System: A Game Changer in Forensic Laboratories

Abstract: Advanced techniques are highly required in forensic science laboratories and law enforcement agencies, such as barcoding, QR code, near-field communication (NFC), and radiofrequency identification (RFID), to track and manage forensic evidence. It is requisite to have a unique code system that will identify evidence and convey all the associated information, making capturing, collection, and transfer of data to track assets in real-time more efficient. Barcodes or QR code tag-identifying systems should be used for identification alerts, and their implementation in forensic laboratories will ease communication between the pillars of the criminal justice system. A barcode or QR code-based digital platform can be used to validate the forensic examiners or elected handlers during the examination process and to gain access based on definite functions and duties. The aim of this article was to increase transparency in the forensic case examination, collection, and transfer of data of forensic evidence in order to enhance the satisfaction and trust of the citizens in the forensic, police, and judiciary systems and minimise the chances of intentional and unintended manipulations. To safeguard evidence's integrity and identity, and enhance its accountability, barcodes or QR codes are placed on evidences that are sent to a forensic science laboratory from the scene of the crime. Thus, a scientific approach to modernizing and upgrading the forensic system is strongly recommended by using such technology.

Rapid Prediction of ANFO Based Explosives through ATR-FTIR Analysis – Use of ATR-FTIR in Explosives

Ammonium Nitrate Fuel Oil (ANFO) is preferred mining explosives in worldwide. It is composed of ammonium nitrate (94-96%) and liquid hydrocarbon as fuel oil (4-6%), which is detonated through an explosive charge. In India, Forensic Science Laboratories received many criminal cases from investigation agencies for chemical analysis of sample as semi-solid materials supposed to be explosive material. In the present study, we developed an Attenuated Total Reflectance - Fourier Transform Infrared Spectroscopy (ATR-FTIR) procedure for easily analyzing the real crime exhibits related to ANFO based explosives. Firstly, semi-solid material is directly used on the ATR. Further, the sample is extracted using appropriate solvents (diethyl-ether/acetone). Extracts are subsequently analyzed on ATR-FTIR in comparison with standards for ammonium nitrate and diesel. The residue after acetone extract is dried and left solid material directly used on ATR for the detection of water-soluble compounds. The results significantly showed the presence of ammonium nitrate with the residue of diesel in a real crime exhibit. Hence, the proposed modify procedure can be advantageous for the rapid detection of diesel components mixed in ammonium nitrate through ATR-FTIR spectroscopy without the use of other chemical or instrumental analysis in a short period of time and also for easily identifying the presence of organic explosives (if any) among different samples received for the forensic opinion.

Development of a New Methodology for Extraction and Analysis of Pesticides, Drugs, Heavy Metals and Various Toxins from Viscera Samples

Viscera analysis plays a major and important role in forensics, Scientists use their own tried and tested methods to avoid excess time consumption and errors, to analyse the viscera samples for the presence of various illicit drugs, pesticides, heavy metals, or any other poisonous substances that may be the reason of death. In this article, the current scenario of viscera handling in forensic science laboratories in India is mentioned in detail with a step-by-step procedure. Tests for phosphine and various pesticides are performed in the stomach and small intestine. Drugs are extracted according to different procedures depending upon the affinity of the drug i.e., acidic, basic, or neutral. After that, Tests for drugs and other toxic substances are usually performed in blood, liver, spleen, and kidney. Blood usually comes in the third jar, and is tested for drugs, alcohol, and maybe for pesticides, phosphine and for any other suspected toxin. Viscera sample needs to be digested before the analysis of heavy metals. Any part of the viscera can be digested and tested for heavy metal. Usually, a mixture of all the viscera parts is digested and analysed. The techniques mentioned in this article are rigorously used in the chemistry and toxicology division in forensic laboratories in India.

A case study for local data surveillance in opioid overdose fatalities in Cuyahoga County, OH 2016-2020

IntroductionFentanyl and fentanyl analogs have increased the overdose mortality rates in the United States, significantly impacting states like Ohio. We examined carfentanil overdose deaths, other contributing Cause of Death (COD) drugs, and drug seizure trends from 2016 to 2020 in Northeast Ohio. Materials and methodsWe studied death investigation data from the Cuyahoga County, Ohio Medical Examiner's Office (CCMEO) of all fatal accidental opioid overdoses as well as drug seizure data from Cuyahoga County Regional Forensic Science Laboratory (CCRFSL). We also compared decedents’ race, gender, age, residential locality, drugs contributing to the COD in opioid cases, and for carfentanil, fentanyl, and cocaine seizures in Cuyahoga County from 2016 to 2020 (N = 2948). ResultsDecedents’ had an average of three different drugs contributing to their COD. A bimodal carfentanil spike was observed in fatal accidental overdoses in Cuyahoga County for the years 2017 and 2019. Decedents in urban residency, who were Non-Hispanic, White and younger, significantly predicted the presence of carfentanil contributing to the COD. In 2020, decedents who were Black and older were significantly associated with cocaine contributing to the COD. Carfentanil and carfentanil-related overdoses were significantly correlated. DiscussionThe pervasiveness of illicitly manufactured fentanyl and fentanyl analog (e.g., carfentanil) mixtures with other drugs are changing the demographics of persons who fatally overdose in Cuyahoga County, OH. Significant trending shifts can also be observed for the presence of carfentanil in decedent and seizure county data. ConclusionsLocal data of drug-related overdose deaths and drug seizures from a medical examiner's office and affiliated forensic laboratory lab can be used for timely public health surveillance, and informing prevention, and intervention at the county level.

Forensic morphological and elemental analysis of gold jewellery: A case study

In a cheating case, report was launched in the police station of Raipur city of Chhattisgarh state. In this case, a person was cheated in buying gold beads worth nearly 16 lakhs. As in forensic physics branch analysis and comparison of physical properties is done, case was registered in state forensic Science Laboratory, Raipur. The aim of this paper is to understand and apply basic principles of physics to solve unsettled cases and create awareness, whenever we purchase precious ornaments. In this case, a garland consisting of large number of round golden beads was received for examination of gold content assuming it to be gold of lower purity. Scanning Electron Microscope (SEM) examination, Energy Dispersive X-ray analysis (EDAX) examination of these beads were done in the laboratory. The results were supervising that there was no Gold (Au) in all the golden beads of garland, it consisted of Copper (Cu) and Zinc (Zn) in the ratio of Cu: Zn::2:1.

Cypermethrin insecticide in viscera of suspected snake bite case: A Forensic case study

The present paper reports the use of analytical techniques in identifying the reason of the death of a suspect. After the death of an individual, a post-mortem examination was conducted. As part of the investigation, the viscera (I) and (II) were sent to the Mini Forensic Science Laboratory in Solapur. The Medical Officer, in their report, mentioned that no injuries or defensive marks were found on the body, except for a small prick mark or bite mark with clotted blood observed on the right foot, between the small toe and adjacent fingers. Upon cleaning the area, it was noticed that one spot was more prominent, while the other spot was faint. Since there were no eyewitnesses present at the crime scene, the police recorded in their inquest that the death might be a result of a snake bite. No formal complaint was registered at that time. However, the viscera samples were preserved for further examination and a final opinion. In the analysis of the viscera, techniques such as Thin-Layer Chromatography (TLC) and Gas Chromatography-Mass Spectrometry (GC-MS) were employed. The results of the analysis revealed that the cause of death was cypermethrin poisoning, as indicated by the presence of cypermethrin in the viscera samples

GC-IR technique a rapid tool for detection of Tramadol in Forensic Confiscated Drugs and Biological Fluids

Tramadol is placed under Drug Controlled Substance Act, in India since 2018, owing to its extensive abuse as a narcotic substance recently. Subsequently, there is increased illegal trafficking across our nation for the drug tramadol. Forensic Science Laboratory, Delhi receives confiscated drugs and toxicological samples for chemical analysis to evaluate their precise composition enabling regulations from law enforcement agencies. Although considered a safe drug for its anti-inflammatory properties when used under medical guidance nevertheless, unintentional fatal tramadol intoxication due to its action on opioid receptors has been reported in several autopsy cases. Contraband tramadol is presently being examined using Gas Chromatography-Mass Spectrometer (GC-MS) and Fourier-transform infrared spectroscopy (FTIR) instrumental techniques in routine forensic examination. In the proposed study, an advanced sensitive technique Gas Chromatography Infrared spectroscopy (GC-IR) was explored as an alternative tool for rapid identification and confirmation. Standard Tramadol was used for method establishment and the method was subsequently applied to seized drug samples and Biological Fluids (blood, and urine samples). Findings of the study indicate that this method can be successfully applied to seized drugs and biological toxicological samples in the forensic examination for the drug Tramadol which was successfully detected by GC-IR. This new rapid analytical method will prove beneficial for the forensic community during routine examination of forensic samples with confirmation.

False-negative probability in the SEM/EDS automated discovery of iGSR particles: A Bayesian approach.

The automated search software integrated with a scanning electron microscope (SEM/EDS) has been the standard tool for detecting inorganic gunshot residues (iGSR) for several decades. The detection of these particles depends on various factors such as collection, preservation, contamination with organic matter, and the method for sample analysis. This article focuses on the influence of equipment resolution setup on the backscattered electron images of the sample. The pixel size of these images plays a crucial role in determining the detectability of iGSR particles, especially those with sizes close to the pixel size. In this study, we calculated the probability of missing all characteristic iGSR particles in a sample using an SEM/EDS automated search and how it depends on the image pixel resolution setup. We developed and validated an iGSR particle detection model that links particle size with equipment registers and applied it to 320 samples analyzed by a forensic science laboratory. Our results show that the probability of missing all characteristic iGSR particles due to their size is below 5% for pixel sizes below 0.32 μm2 . These findings indicate that pixel sizes as large as twice the one commonly used in laboratory casework, that is, 0.16 μm2 , are effective for initial sample scanning, yielding good detection rates of characteristic particles that could exponentially reduce laboratory workload.

GC-MS analysis of eight aminoindanes using three derivatization reagents.

Aminoindanes are a class of novel psychoactive substances (NPSs) that have become more prevalent over the past decade. GC-MS is often utilized for identifying seized drugs and is well regarded for its ability to separate mixtures. However, certain aminoindanes have similar mass spectral data and require specific gas chromatographic stationary phases for separation. Derivatization is an alternative method that can be applied to GC-MS to enhance chromatographic results, providing more selective analysis in seized-drug identification. This study investigates derivatization techniques to provide options for forensic science laboratories in accurately identifying aminoindanes. Three derivatization reagents, N-methyl-bis(trifluoroacetamide) (MBTFA), heptafluorobutyric anhydride (HFBA), and ethyl chloroformate (ECF) were evaluated for the analysis of eight aminoindanes by GC-MS using two common gas chromatographic stationary phases, Rxi®-5Sil MS and Rxi®-1Sil MS. All three derivatization methods successfully isolated eight aminoindanes, including the isomers 4,5-methylenedioxy-2-aminoindane (4,5-MDAI), and 5,6-methylenedioxy-2-aminoindane (5,6-MDAI) that could not be differentiated prior to derivatization. Reduced peak tailing and increased abundance were observed after derivatization for all the compounds, and mass spectra of the derivatives contained individualizing fragment ions that allowed for further characterization of the aminoindanes. This excluded 4,5-MDAI and 5,6-MDAI as they shared the same characteristic ions and were only distinguishable by their retention times. All three derivatization techniques used in this study allow for successful characterization of the aminoindanes and give forensic science laboratories flexibility in their analysis approach when they encounter these compounds.