Browsing by Department "Division of Forensic Medicine and Toxicology"
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- ItemOpen AccessThe analysis of the artefacts produced by forensically significant blowfly (Diptera: Calliphoridae) activity and their effect on bloodstain pattern analysis(2016) Lesaoana, Mpasi Pascalis; Heyns, Marise; Mole, Calvin GeraldViolent crimes involving bloodshed may result in bloodstains spattering on the surrounding surfaces. Accurate analysis of bloodstains at the scene can provide investigators with insights into the series of events that occurred during the execution of a violent crime. At a crime scene, blowflies feed on bloodstains and deposit artefacts that may cause confusion during crime scene reconstruction. Experimental cages of two possible crime scene surfaces (paper to simulate wallpaper and linoleum) were developed such that fly artefacts can be characterized and differentiated from legitimate bloodstains. Pooled bloodstains were created within the experimental cages and blowflies were allowed access to the cages. A total of 10739 and 740 artefacts deposited on paper surfaces and linoleum walls respectively were examined. Clear differences between fly artefacts and legitimate bloodstains were noted and unique characteristics of fly artefacts resembling true blood spatters with a possibility of confounding crime scene reconstruction were distinguished.
- ItemOpen AccessAnimal attacks - a red herring of child abuse?(2006) Van As, A B; Kalebka, Robert R; Van der Heyde, YolandeInjuries sustained as a result of attacks by domestic animals, particularly canines, are occasionally encountered at the Red Cross Children’s Hospital Trauma Unit in Cape Town. Less than 1% of admissions are directly attributable to animal attacks. Animal attacks causing lethal injuries are very rare and should be assessed carefully. We recently dealt with two fatalities attributed to animal attacks.
- ItemOpen AccessAssessment of 13 Forensic Molecular Markers for skin colour in South Africa(2018) Pharo, Gavin; Heathfield, LauraMolecular phenotyping is the use of informative genetic variation to estimate appearance. This concept can be applied in a forensic context to predict the appearance of suspects or decayed deceased individuals, which would otherwise remain unidentifiable. This concept has importance in a local context, as approximately 300 individuals remain unidentified, after conventional identification techniques, at Salt River Mortuary, every year. Ancestry Informative Markers (AIMs) are genetic variants with DNA which have been commonly associated with pigmentation phenotypes, and thus has value in predicting skin tone, hair colour and eye colour. This research study aimed to design and optimise an assay to genotype 13 AIMs associated with pigmentation, and then demonstrate the value of this assay by applying it to a case example and qualitatively predicting appearance. Primers were designed and PCR assays optimised to amplify each region, followed by Sanger sequencing on a case example. The case was that of an abandoned neonate, with unknown sex and ancestry. A comparison of the obtained genotypes to previous literature was performed to qualitatively estimate the skin tone, eye colour and hair colour of the decedent, which was not only in agreement with the forensic pathologist’s interpretation of sex and ethnicity, but provided richer detail with regards to ancestry, skin tone, eye colour and hair colour. The PCR assays were then further optimised into four multiplex assays with the intention of genotyping these AIMs by two SNaPshot® PCR assays (Applied Biosystems) in a larger control cohort to model the relationship between these AIMs and melanin index more objectively. Unfortunately, the scope of this research project did not allow for the completion of this additional aspect. Overall, these results indicate that these 13 AIMs have potential to predict pigmentation phenotypes of South African individuals. However, genotyping and modelling of the effects of these AIMs should be performed on a large cohort to further strengthen this conclusion.
- ItemOpen AccessThe assessment of the utility and impact of sexual assault evidence collection kits (SAECKS) as DNA evidence in suspected cases of rape(2014) Cupido, Danielle; Heyns, MariseThe results from this study show the value of good basic medical practices in documentation of injuries, rather than more costly DNA evidence, in assisting courts in rape cases. However, the researchers do argue that in South Africa, as a middle-income country with a high percentage of non-intimate partner rapes, there would be an advantage in improving the system to collect and analyse DNA evidence rather than abandoning it completely. These results taken together suggest that DNA evidence can assist in signifying that sexual act has transpired however it is more likely that convictions will occur if evidence of physical injury is available, as DNA evidence cannot reveal if consent was obtained or not. As stated above South Africa has one of the highest rates of rape worldwide.
- ItemOpen AccessComplementary and alternate medicines: a forensic analysis of the potential adulteration of over-the-counter anorectics and "lifestyle" medicines in South Africa(2017) Catterson, Sandra Lynne; Davies, Bronwen; Smith, Peter; Aukloo, Kathrina MendozaBackground: Complementary and Alternate Medicines (CAMs) in South Africa are not yet subjected to the same rigorous testing required for allopathic (prescription) medication, yet they are freely available as over-the-counter medicines. Past research has shown the presence of a banned drug, sibutramine in natural anorectics and a schedule 6 prescription drug, sildenafil, found in natural erectile dysfunction preparations. Methods: Initially, 26 exhibits (18 erectile dysfunction medicines and 8 anorectics) were screened for active pharmaceutical ingredients using high performance liquid chromatography tandem mass spectrometry. An AB SCIEX 3200 TRAP® linear ion-trap quadrupole mass spectrometer was used to detect and subsequently quantitate these active pharmaceutical ingredients using a targeted multiple reaction monitoring mode. Samples were extracted with 50% v/v methanol in water. A method for the quantitation of sildenafil was subsequently partially validated. The intra- and inter-assay precisions were evaluated and the linearity of the method was investigated in the range of 20 ng/mL to 2000 ng/mL. The method was then successfully applied to a random selection of CAMs. A random sample (n=61) of erectile dysfunction CAMs were selected for quantitation from two different clusters. Cluster 1 comprised of supermarkets and cluster 2 of pharmacies. Results: The validation method for sildenafil showed that the limit of detection was 1.09 ng/mL and the limit of quantitation was 20 ng/mL. The correlation co-efficient and bias were less than 20%. Initial screening of the 26 exhibits indicated that sildenafil was present in 12 of the 18 samples tested and sibutramine in 6 of the 8 anorectics. Of the later 61 exhibits tested, 43 tested positive for sildenafil. The mass of sildenafil per sample ranged from 1.09 ng/mL to 123.7 mg/sample. Conclusion: The lack of label content, regulation and legislation exposes the consumer to the risk of consuming an active pharmaceutical ingredient which may very likely have an adverse effect on their health. There is a need to raise public awareness to the potential dangers of unregulated CAMs, encourage doctors to become more aware of their patients' consumption of CAMs and to motivate the Medicines Control Council to follow through with their deadlines for the regulation of CAMs.
- ItemOpen AccessConstructing a DNA profile frequency database for South Africa using the Qiagen Investigator 24plex GO! Kit(2018) Nel, Lorraine; Heathfield, Laura JDNA profiling is routinely used in the forensic setting to identify individuals during criminal and medico-legal investigations. Its principle is based on the molecular analysis of DNA to produce a string of alpha-numeric characters which can be matched to a known reference sample. The use of allele frequencies from the background population aids the statistical interpretation of a match and can be used to calculate the random match probability. In South Africa, allele frequency data for the background population is currently limited, which can hinder the discriminatory value of DNA evidence, particularly when only a partial profile is obtained. Therefore, the aim of this study was to generate DNA allele frequency data for four South African population groups using the QIAGEN Investigator® 24PLEX GO! Kit, which has six markers for which data does not yet exist for the South African population. Full forensic DNA profiles were generated from 655 unrelated individuals from four population groups in South Africa: Black African (n = 172), Coloured (n = 195), Indian/Asian (n = 88) and White (n = 200). A 98% first time success rate was observed using the direct PCR approach. Allele frequencies were significantly different between all four population groups at three markers (D8S1179, D2S1338 and D2S441) after a Bonferroni correction (ρ < 0.001) and sixteen novel alleles were observed. Two genetic anomalies were observed, namely triallelic patterns at the TPOX marker (n = 9) and a null allele at amelogenin (n = 1). While the sample size for the Indian/Asian population group was limited in this study, the data generated here nevertheless prospects to contribute towards the data currently published for South Africa. This, in turn, will allow for more DNA markers to be analysed during forensic casework in South Africa, as the data for its statistical interpretation is now available.
- ItemOpen AccessThe contribution of respiratory pathogens to Sudden Unexpected Death in Infancy(2016) Ishimirwe, Elyse Sandrine; Kaba, Mamadou; Heyns, MariseBackground: Sudden unexpected death in infancy (SUDI) is among the most frequent causes of mortality in infants less than one year of age. Respiratory infections have been identified as the most frequent cause of death in these infants. Yet, the broad range of respiratory pathogen that might be involved in SUDI is poorly studied. This study aimed to investigate the incidence of the respiratory pathogens in SUDI. Methods: A prospective study was carried out on SUDI cases admitted to Salt River Forensic Pathology Laboratory from February 2015 through May 2015. Cerebrospinal fluid, pericardial fluid and lung biopsy were collected from each study participant during post-mortem examination. Total nucleic acids were extracted on the automated QIAsymphony platform. The microbial diversity was investigated using a commercialized multiplex real-time PCR assay, the "FTD Respiratory pathogens 33" kit. This assay is able to detect 21 viruses, 11 bacteria and one fungus. In each real-time PCR run, a positive and non-template sterile water were included as controls. Results: Thirty SUDI cases (median age, 3 (interquartile range (IQR): 2 - 8 months) were included in the study. Twenty participants were males. Positive microbiological results from at least one of the three samples were obtained in 28 cases (93%). According to the type of sample, respiratory pathogens were detected in almost all the lung biopsies (93%), while it was only detected in 60% and 50% of the cerebrospinal and the pericardial fluids, respectively. The median cycle threshold value was lower in lung biopsies (30 (IQR: 28 ‒ 35)) compared to both cerebrospinal (34 (IQR: 30 ‒ 36)) and pericardial fluids (35 (IQR: 33 ‒ 35)) (p= 0.039). In lung biopsies, the most commonly detected bacteria were K. pneumoniae (47%, 14/30) and M. catarrhalis (20%, 6/30). H. influenza (7%, 2/30) and M. pneumoniae (7%, 2/30) were the bacteria often detected in pericardial fluid and cerebrospinal fluid, respectively. Human Metapneumovirus was the most frequently virus detected in all three sample types assessed, accounting for 33% (10/30) in cerebrospinal fluid, 37% (11 /30) in pericardial fluid and 57% (17/30) in lung biopsy samples, respectively. A single type of pathogen was detected n seven of the 28 positive cases. Conclusion: This study highlights the potential implication of respiratory infection in SUDI and it reports one of the highest incidences of respiratory pathogens in SUDI cases. In addition, it is the first to report the high incidence rate of Human Metapneumovirus in SUDI cases. The findings also showed that the majority of SUDI cases are associated with synergetic interaction of multiple respiratory infections. However, data related to histopathology and bacterial culture were not available. A broad range of respiratory pathogens should be included in the routine investigation of SUDI cases with more sensitive diagnostic methods.
- ItemOpen AccessDeaths in police custody in the Cape Town Western Metropole 2000-2009(2015) Afonso, Estevão Bernardo; Van der Heyde, YolandeDeaths in police custody are a global phenomenon which continues to beset policing services worldwide. Research into these deaths has provided insight into the complexity of detention and led to the institution of preventative strategies which have seen a reduction in mortality internationally. An improved understanding of the South African detention milieu may similarly assist in reducing the mortality burden in this country. This study retrospectively reviewed deaths in custody in the Cape Town Western Metropole between 2000 and 2009, with the aim of identifying local, modifiable factors to aid in death prevention. Sixty two (62) cases were reviewed. Males predominated (90.3%) in the sample, with the racial profile mirroring that of the general population. The median age of the detainees was 30.5 years. Unnatural causes of death accounted for 82% (n=51) of cases, with suicidal hanging the commonest cause (n=40). Items of clothing were used as ligatures in 80% of hangings, with gate and window bars the most common points of suspension. Time in detention averaged 863 minutes for the sample. Clinical signs of intoxication at the time of arrest was identified as a statistically significant determinant (p=0.02) of a shorter detention time (446 minutes). Ten (10) detainees were identified as either injured at the time of arrest or physically ill during detention, of which 9 succumbed to their injuries or disease. Only three of these detainees received medical attention. These findings highlight the need for urgent review of local police cell architecture to ensure an environment conducive to safe detention, with particular attention to reducing potential points of suspension for hangings. Further, the healthcare needs of detainees must be prioritised through effective training of police personnel with regard to the assessment and management of ill detainees, particularly those intoxicated at the time of arrest.
- ItemOpen AccessDevelopment and partial validation of a method for the quantification of benzodiazepines and antidepressants in whole blood, serum and urine by liquid chromotography - Tandem mass spectrometry(2015) Pieters, Janke; Smith, PeterThe aim of this project is to develop a single quantification method for certain benzodiazepines, opiates and antidepressants in whole blood, serum and urine by LC-MS/M5 and to consequently validate the analytical method for official use in the Division of Pharmacology at the University of Cape Town.
- ItemOpen AccessDevelopment of a method for the screening and quantification of methamphetamine, and its major metabolite amphetamine, in hair using liquid chromatography-tandem mass spectrometry(2015) Johnston, Jenna; Smith, Peter; Heyns, MariseHair has, over recent years, become widely recognised as an alternate or complementary matrix to blood and urine for drug analysis. Hair analysis offers a wider detection window after drug exposure than blood or urine testing and can provide a long-term history of an individual’s drug use. There are several practical applications of hair analysis for drugs including workplace drug testing, doping control, driving licence re-granting, drug-related deaths and drug-facilitated crimes. As a result hair analysis is currently being performed within various toxicological fields in laboratories around the world. However, before the start of this study no hair analysis for drugs was being performed in South Africa. Therefore, the main aim of this study, as stated in Chapter 1, was to develop a method for the detection and quantification of drugs of abuse, specifically methamphetamine and amphetamine, in hair using High Performance Liquid Chromatography coupled to Mass Spectrometry.
- ItemOpen AccessDNA barcoding of forensically important flies in the Western Cape(2016) Cooke, Tenielle Monique; Heyns, Marise; Heathfield, LauraOne of the central applications of forensic entomology is the determination of the post mortem interval (PMI) from arthropod evidence associated with a corpse. Estimations of the PMI are based on succession and developmental patterns of specific species that visit the body. As first colonisers, Calliphoridae (blow flies) are often used by forensic entomologists to determine the PMI however, developmental rates of visiting fauna differ substantially which makes correct species identification vital. Traditional methods of identification which assign species based on keys that capitalise on morphological differences are insufficient for closely related species, especially during immature stages of the lifecycle or when the specimen is damaged. Molecular identification such as DNA barcoding has therefore become a popular method of identifying species. DNA barcoding characterises species by sequencing and analysing specific regions in the genome. This technique has been used to characterise species in various countries including parts of South Africa. Its application has also been demonstrated in a forensic setting but data for the Western Cape is minimal. This study therefore aimed to assess the utility of DNA barcoding for species level determination of four blow fly species common to the Western Cape of South Africa (Chrysomya chloropyga, Chrysomya albiceps, Chrysomya marginalis, and Lucilia sericata) as well as its ability to identify immature specimens. Ten adult specimens from each species were morphologically and molecularly identified using microscopy and DNA barcoding respectively. The standard DNA barcode, cytochrome c oxidase subunit I (COI) and a secondary marker, the second internal transcribed spacer (ITS2) were analysed. Phylogenetic analyses for both barcodes showed high interspecific divergence values which are desirable for species level differentiation by DNA barcoding. COI sequences from adult flies were also submitted and searched against BOLD for identification and only genus level identity could be achieved, indicating that, COI alone may be insufficient to discriminate between closely related species. DNA sequences from the adult specimens were then used as reference sequences for identification of seven unknown immature specimen using DNA barcoding of both COI and ITS2. Sequence similarity was assessed and identity was assigned based on >98% similarity scores, and all immatures were successfully identified. The use of more than one DNA marker to complement morphological data ensures higher confidence of species level identification. This method provides a reliable and consistent tool for entomologists to use for species identification which results in higher levels of accuracy in PMI estimations.
- ItemOpen AccessDoes the Insanity Defence lead to an Abuse of Human Rights?(2012) Kaliski, S ZEvery day convicted murderers, rapists, and other violent offenders are released by the prisons into the community. Most have not even completed their sentences, as they earned remittances for good behaviour. No one seems to worry that statistically many of these former prisoners remain dangerous, and will probably harm others sometime in the future. 1 In fact, there are criminologists who argue persuasively that fewer offenders should be imprisoned, for the good of their families and communities. This may reflect the confusion about what the actual purpose of imprisonment is, ranging from urges for retribution to achieving rehabilitation. Nevertheless, we are satisfied that when an offender ‘has repaid his debt to society’ he is free to re-enter ordinary life, albeit for a while under the sometimes wavering, watchful supervision of a parole officer.
- ItemOpen AccessEntomological examination of the relationship between ante-mortem and post-mortem amitriptyline concentrations in insects(2016) Sanyanga, Taremekedzwa; Heyns, Marise; Mole, Calvin GeraldWhen the death of an individual has occurred, the body of the deceased is not always discovered immediately and at times the body may be discovered after a long period of time. The consequence of discovering a body after a long period of time is that the body maybe found severely decomposed or skeletonized. As a result no viable blood, urine or tissue samples may exist that can be collected and utilized in toxicological analyses. Entomotoxicology offers a supplementary method to detect and analyse the presence of drugs post-mortem, especially in cases where viable toxicological specimens such as human tissue cannot be obtained. In South Africa and globally, standardised methodology is required to perform entomological examinations accurately, however due to the large variation of experimental set-up no such standardised methods yet exist. The main aim of the research was to analyse the effect of Amitriptyline on the development and growth rate of forensically important blow flies, and to investigate the potential in using blow fly larvae of the Western Cape, South Africa in forensic entomotoxicological analyses and future implementation. To achieve this blow fly species C. chloropyga and L. sericata were reared on homogenised pig liver containing 1000 mg/kg Amitriptyline until emergence of imago. The duration of time taken by the blow fly larvae species to reach 1 st , 2 nd , 3 rd , pupae and imago growth stages in the presence and absence of Amitriptyline was noted. The presence of drugs in larvae was investigated using high-pressure liquid chromatography coupled with dual mass spectrometry (HPLC/MS-MS). Amitriptyline was detected in all experimental larvae samples and was found to delay pupation by at least 26 hours and imago emergence by at least 72 hours. Amitriptyline however showed no distinct effect on C. chloropyga length and mass but was associated with a smaller length and mass in L. sericata compared to controls. Results indicate that entomotoxicology can be of use for qualitative analysis for the presence of Amitriptyline in forensic cases. Results also highlight the unpredictability of research using biological specimens.
- ItemOpen AccessThe epidemiology, pathology and toxicology of suicide(1998) Lourens, Denise; Knobel, G JComplete suicides and parasuicides are a major cause of death and disability in South Africa and the rest of the world. The epidemiology, pathology and toxicology of complete suicides were investigated in this study. All the complete suicide cases, which were presented to Salt River Medicolegal Laboratory over a period of one year (1 January 1997 - 31 December 1997), were analysed. The candidate personally conducted 148 of the alleged 180 suicide cases that presented in this time period (82%). The candidate did all the follow up investigations herself. The main findings were: 1. The male to female ratio was 5: 1. (131: 26) 2. Shooting and hanging were the most commonly used methods. 3. The racial distribution of violent deaths showed a high rate of suicides amongst the White population. 4. Suicides accounted for the Joss of young lives, the average age being 37,8 years. The mean age was 34 years. 5. Most victims committed suicide in and around their own homes. 6. The majority did not leave suicide notes. 7. Psychiatric disorders, poor health, arguments with close family members and friends, financial problems and long-standing relationship problems were the most common reasons for the suicides. 8. Suicides by prisoners accounted for 3,8% of the study (6 cases). 9. Two cases of double suicide (group suicide) were identified. 10. Five cases of homicide-suicide were identified in the study material. 11. One case of an attempted suicide by means of a high-speed motor vehicle accident, followed by the successful suicide by other means, was identified.
- ItemOpen AccessEthical considerations in forensic genetics research on tissue samples collected post-mortem in Cape Town, South Africa(BioMed Central, 2017-11-29) Heathfield, Laura J; Maistry, Sairita; Martin, Lorna J; Ramesar, Raj; de Vries, JantinaBackground: The use of tissue collected at a forensic post-mortem for forensic genetics research purposes remains of ethical concern as the process involves obtaining informed consent from grieving family members. Two forensic genetics research studies using tissue collected from a forensic post-mortem were recently initiated at our institution and were the first of their kind to be conducted in Cape Town, South Africa. Main body: This article discusses some of the ethical challenges that were encountered in these research projects. Among these challenges was the adaptation of research workflows to fit in with an exceptionally busy service delivery that is operating with limited resources. Whilst seeking guidance from the literature regarding research on deceased populations, it was noted that next of kin of decedents are not formally recognised as a vulnerable group in the existing ethical and legal frameworks in South Africa. The authors recommend that research in the forensic mortuary setting is approached using guidance for vulnerable groups, and the benefit to risk standard needs to be strongly justified. Lastly, when planning forensic genetics research, consideration must be given to the potential of uncovering incidental findings, funding to validate these findings and the feedback of results to family members; the latter of which is recommended to occur through a genetic counsellor. Conclusion: It is hoped that these experiences will contribute towards a formal framework for conducting forensic genetic research in medico-legal mortuaries in South Africa.
- ItemOpen AccessEvaluating the role of DNA evidence in sexual offence cases in Zambia between 2007 and 2014(2017) Makasa, Innocent; Heathfield, LauraZambia has reported high incidences of sexual abuse against women and children in recent years. Zambian law categorises sexual offences into; rape, defilement, incest and others, with defilement constituting the majority of the cases (>89%). Between 2010 and 2012, only <39% of defilement cases were taken to court, and convictions were achieved in only 13% of the cases reported to the police. Literature was reviewed to determine factors which contributed towards the resolution of criminal cases, and it was found that DNA evidence was prominent in resolving crimes, specifically as an identification tool in sexual offences. Currently there is no empirical evidence describing how DNA evidence has been used in resolving sexual crimes in Zambia. The causes of low prosecution and conviction rates have also not been investigated. A retrospective study was therefore conducted to evaluate the role of DNA evidence in sexual offence cases in Zambia, reported to eight major police stations in Lusaka between 2007 to 2014 (n=1154). Sexual offence cases comprised rape (n=74, 6.4%), defilement of a child under the age of sixteen years (n=1028; 89.1%), incest (n=7; 0.6%) and others (n=45; 3.9%). Only 14 (0.1%) of the cases had forensic samples collected in the form of a vaginal swab for the sole purpose of determining the presence of semen. In all cases where a suspect was identified (60%), identification was based on the witness/victim testimonies, and in no case was forensic DNA evidence used to assist in identification or corroborate the testimonies. Overall, 28.1% cases were taken to court and the conviction rate was 12.4%. If no injuries were observed on a victim aged between 0 - 5 years, the case was not taken to court. It was also observed that the younger the victim, the more likely the accused was not identified (p < 0.001), victims did not know the date of occurrence (p < 0.001), and the case was closed due to insufficient evidence. These findings support the use of employing forensic DNA evidence in sexual offence cases to aid the identification of suspects, either in the absence of witness/victim testimonies or alongside as corroborative evidence, which is hypothesised to increase the number of cases prosecuted in Zambia. At the time of this study there was no standardised protocol for the forensic investigations of sexual offences in Zambia, which to some extent, led to numerous missing data. Development and use of the national protocol and use of a validated sexual assault evidence collection kit may help mitigate the deficiencies and inconsistencies witnessed during this study.
- ItemOpen AccessThe evaluation of tests for the identification of semen(2016) Curry, Lyle; Heathfield, LauraThe identification of bodily fluids for forensic purposes is typically classified as either presumptive or confirmatory. Presumptive tests (PT) are conducted first to screen for certain compounds which are relatively specific to particular fluids. Confirmatory tests are used to confirm the identity of a body fluid. Semen is one of the most common bodily fluids encountered in sexual assault cases and contains high concentrations of the acid phosphatase (AP) enzyme. The brentamine FB reagent reacts with the AP that is present in semen, and turns purple. If the colour change is observed within a specific time threshold, it is considered presumptively positive for semen. Cut-off time varies considerably between forensic laboratories, but in South Africa, the cut-off time is defined as 65 seconds. Additionally, semen may be considered to be from human origin if it reacts within 50 seconds. These cut off times have been arbitrarily defined, and there is little research in a local context to substantiate or inform the threshold time for the brentamine FB test for semen. Therefore this study assessed the sensitivity, specificity and kinetics of the brentamine FB test on semen from South African male volunteers (n=15), canines (n=2) and various fruit extracts and compared these results to purified human AP. Each semen sample was subjected to the PT in an indirect and direct method, and these tests were performed both on fresh and aged samples. The majority of fruit extracts yielded a distinctly different colour change compared to the purple that was produced from semen except for mushroom which also turned purple. Absorbance spectroscopy was used to determine the rate of the reaction at 525 nm. There were no significant differences between the rate of reaction for fresh and aged samples using both direct and indirect testing.
- ItemOpen AccessFatal penetrating injuries of the chest(1996) Scholtz, Hendrik Johannes; De Groot, K MIn the Republic of South Africa, an autopsy is required in all cases of unnatural death, or in cases where the cause of death is unknown in terms of the Inquest Act of 1959. These are performed at the Salt River Medicolegal Laboratory by Forensic Pathologists and Registrars of the Department of Forensic Medicine and Toxicology of the University of Cape Town. The Salt River Medicolegal Laboratory serves the greater Cape Town area with a population of approximately 2,5 million, including the magisterial districts of Cape Town, Wynberg, Mitchell's Plain and Simonstown. Cape Town has one of the world's highest homicide rates and in 1986 the incidence was 56, 91 100000 population per annum. In contrast, Singapore has a homicide rate of only 2, 5/100 000, while the United States has an overall homicide rate of 7,7/ 100 000 population. In order to document the true impact of penetrating chest injuries, and to place mortality data in perspective, a retrospective descriptive study of all cases with fatal penetrating chest injuries admitted to the Salt River Medicolegal Laboratory in Cape Town during 1990 was undertaken. In 1990, a total of 5 758 cases was admitted to the Salt River Medicolegal Laboratory of which 1834 cases (39%) were the result of homicide. Of the homicide cases, 408 (22%) were the result of firearm injuries. A total of 2044 (35, 5%) cases admitted was deemed to have died of natural causes. This study identified a total of 841 cases of fatal penetrating injuries of the chest admitted during 1990, which constituted 22,6% of all non-natural cases admitted.
- ItemOpen AccessFirearm fatalities examined at Salt River Medico-Legal Laboratory in 2009 and their investigative outcome by 2014(2016) Wichers, Ansie; Liebenberg, Linda; Heyns, MariseSouth Africa has a very long history of gun violence, particularly politically motivated. The politically motivated gun violence did subside after 1994, however there was an increase in criminal gun violence. In 2004 Dr Liebenberg from the University of Cape Town conducted a study on the victimology and investigative outcomes of firearm deaths of 1999 in the Salt River Medico - Legal Laboratory drainage area. There were some compelling results, including a remarkably low conviction rate of 7.21%. In 2000 new legislation was enacted, which is the Firearms Control Act (1) of 2000 and from 2001 to 2005 there was a 13.6% decrease in firearm homicides which was consistent after the introduction of the new act, likely due to the decrease in the number of firearms in circulation. Because of the changes in firearm legislation and reported crime rates, it was decided to conduct a follow - up study one decade later, looking at the investigative outcomes of firearm deaths to see whether the decreased contribution of firearms in homicides and crime made an impact on the investigative and judicial process of the Salt River Medico - Legal Laboratory cases. In 2009 there were 281 firearm deaths investigated at Salt River Medico - Legal Laboratory as opposed to 532 in 1999. In 1999, 89.29% of firearm deaths were due to homicide as opposed to 86.12% in 2009. In 1999 the majority of firearm homicide victims were Black and Coloured males between the ages of 21 and 30 years, this is similar to what is seen in 2009, however there were fewer Coloured victims in 2009. In both years homicides occurred more often on weekends, at night time. In 1999 there were peaks in May and then from October through to December. In 2009 however, the peaks were in March, May and August. One might thin k that with such a large decrease in the number of firearm deaths (not considering other crime trends), the criminal justice system might have fewer cases to investigate and prosecute and that the investigative outcomes (particularly conviction rate) of th ese cases might improve. Even though there was a significant drop in the number of firearm deaths in 2009, there has been no improvement in the conviction rate, with 2009 having a rate of 5.69%. The number of cases still being investigated was also similar at 104 cases (37.01%) for 2009 versus 182 cases (34.54%) for 1999. In 2009 only 58 (20.64%) cases completed the judicial process by 2014, which includes the 16 cases (5.69%) that ended in a guilty verdict, 18 (6.41%) cases where a suspect was acquitted (not guilty) and also 24 (8.54%) cases that were withdrawn in court. Of the 281 cases for 2009, 10 (3.56%) were still in court, which was significantly less than the 59 (11.20%) cases in 1999. From 2009 there were 87 cases that reached an impasse (30.96%) by 2014, as opposed to the 114 (21.63%) cases from 1999 by 2004, which is a statistically significant difference.
- ItemOpen AccessFirearm-related injuries in Cape Town children and youth 1992-1996(2000) Wigton, Alyssa; Bass, DavidThe aim of this study was to determine the epidemiological profile of firearm-related injuries among children and youth under 19 years of age in Cape Town during the period 1 January 1992 - 31 December 1996. The purpose of the study was to make recommendations for future research, policies, prevention programmes and surveillance.
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