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Item Occupational Exposures And Epigenetics Alteration Among Electronic Waste Workers At Agbogbloshie, Ghana(University Of Ghana, 2022-09) Issah, I.Background: The techniques used in the informal recycling of e-waste, particularly in low- and middle-income countries (LMICs), are unsophisticated and rudimentary without safeguards for the health and safety of humans and the environment. Particulate matter (PM), including toxic chemical components in the form of metallic and organic compounds are generated and released into the environment during informal e-waste recycling activities. Available data suggests that PM and metals are among the most important risk factors for developing many chronic diseases such as cardiovascular diseases, neurological diseases, reproductive toxicity, renal dysfunction, autoimmune diseases and cancers. Due to the deleterious effects of PM and metals on human health, as well as elevated levels detected in occupational environments, there is a need to determine the intermediate health outcomes associated with pollutants exposure before the onset of clinical occupational disease. Epigenetic modification such as DNA methylation are highly suspected as an intermediary between environmental and occupational exposures and adverse health outcomes. Although research has been carried out on the adverse health effects of e-waste recycling in Ghana and elsewhere, there is still little published data examining the effects of metals and PM on DNA methylation in occupationally exposed populations especially those in the informal sector such as e-waste recyclers. Objective: The objective of this work was to examine the effects of personal particulate matter exposure and a mixture of metals on global DNA methylation among e-waste recyclers and a reference population. Methods: This study made use of biological samples and exposure data collected during the first round of a parent/larger GEOHealth II study - a longitudinal study. One hundred (100) male e-waste workers and fifty-one (51) male non-e-waste workers serving as a reference population were recruited at baseline. The participants provided survey data and blood samples for measurements of concentrations of metals as well as DNA methylation analysis. The methylation levels of long interspersed nucleotide repetitive elements-1 (LINE-1) was measured by pyrosequencing bisulfite-converted DNA from whole blood as a proxy for global DNA methylation. Personal PM2.5 and PM10 were measured over a 4-hour work-shift using real-time particulate matter monitors incorporated into a backpack and worn by study participants (e-waste workers and reference population). The concentrations of selenium (Se), zinc (Zn), manganese (Mn), cadmium (Cd) and lead (Pb) were measured in blood using inductively coupled plasma mass spectrometry (ICPMS). Descriptive statistics were used to determine differences in participant’s characteristics. Multiple linear regression model with robust standard errors (SE) from ordinary least squares (OLS) was used to evaluate the associations between PM and metals exposure on the one hand and LINE-1 DNA methylation on the other hand. Further, ccorresponding interaction terms were incorporated into the regression model to determine possible modification effect of selected toxic metals (Cd and Pb) on DNA methylation caused by essential metals (Mn, Se and Zn) concentrations. Lastly, a further sensitivity analysis using different variants of the outcome model (robust and cross-fit partialling-out least absolute shrinkage and selection operator (LASSO) linear regression models) were performed to compare with the results of the OLS with robust SEs. Results: Personal median concentrations of PM2.5 and PM10 were significantly higher among the e-waste workers than the reference population (PM2.5: median (interquartile range) 77.32(34.08) μg/m3 vs 34.88 (16.55) μg/m3, p < 0.001 and PM10: median (interquartile range) 210.21 (93.32) μg/m3 vs 121.92 (82.93) μg/m3, p < 0.001, respectively). Overall, metals (Cd, Mn, and Se) were significantly higher in the reference group (geometric mean: Cd = 0.8μg/L, Mn = 14.7 μg/L, and Se = 190.5 μg/L) than those in the e-waste worker group (geometric mean: Cd = 0.6 μg/L, Mn = 11.4 μg/L, and Se = 147 μg/L). Only Pb was significantly higher in the e-waste workers (geometric mean: Pb = 79.6 μg/L) compared to the reference group (geometric mean: Pb = 37.7 μg/L). There was no significant difference in LINE-1 methylation among the e-waste workers and the reference group (85.16 ± 1.32% vs 85.17 ± 1.11%, p=0.950). In the linear regression models controlling for confounders, the associations between PM2.5 and PM10, and LINE-1 DNA methylation were not statistically significant among the e- waste workers (βPM2.5 = 0.004; 95% CI; -0.001, 0.010, p = 0.114), and (βPM10 = 0.002; 95% CI; -0.001, 0.005, p = 0.088), respectively and reference population. For metals exposure, the OLS results of multiple metals showed a significant inverse association between Zn and the LINE- 1 DNA methylation among only the e-waste workers (βZn = -1.180, 95% CI: -2.199, -0.161, p = 0.024) which corresponds to a 0.012 decrease in LINE-1 DNA methylation (95% CI: -0.022, -0.002, p = 0.024) for a 1% increase in Zn concentration. The linear regression results from OLS with robust SEs and those of the sensitivity analysis yielded similar estimates of the beta- coefficients. Potential interactions between toxic and essential metals on global DNA methylation were observed. Conclusion: In conclusion, the high concentration of breathing zone PM and the body burden of metals detected in both the e-waste workers and reference population in Ghana shows the elevated levels of air pollutants in urban Ghana, particularly the capital city, Accra. Overall, PM concentration did not show significant association with LINE-1 DNA methylation in both the e-waste workers and the reference population. However, for metals exposure, increased blood zinc levels showed a significant decrease in LINE-1 methylation only among the e-waste workers. The results of this study further revealed that alteration of DNA methylation by toxic metals could be modified due to the concentration of essential metals. The alteration of LINE- 1 methylation by metals could serve as an early epigenetic marker for future adverse health outcomes in e-waste workers and other workers with similar exposure. Therefore, effective interventions to improve occupational safety for e-waste recycling workers are urgently needed.Item Occupational Exposures And Epigenetics Alteration Among Electronic Waste Workers At Agbogbloshie, Ghana(University Of Ghana, 2022-09) Issah, I.Background: The techniques used in the informal recycling of e-waste, particularly in low- and middle-income countries (LMICs), are unsophisticated and rudimentary without safeguards for the health and safety of humans and the environment. Particulate matter (PM), including toxic chemical components in the form of metallic and organic compounds are generated and released into the environment during informal e-waste recycling activities. Available data suggests that PM and metals are among the most important risk factors for developing many chronic diseases such as cardiovascular diseases, neurological diseases, reproductive toxicity, renal dysfunction, autoimmune diseases and cancers. Due to the deleterious effects of PM and metals on human health, as well as elevated levels detected in occupational environments, there is a need to determine the intermediate health outcomes associated with pollutants exposure before the onset of clinical occupational disease. Epigenetic modification such as DNA methylation are highly suspected as an intermediary between environmental and occupational exposures and adverse health outcomes. Although research has been carried out on the adverse health effects of e-waste recycling in Ghana and elsewhere, there is still little published data examining the effects of metals and PM on DNA methylation in occupationally exposed populations especially those in the informal sector such as e-waste recyclers. Objective: The objective of this work was to examine the effects of personal particulate matter exposure and a mixture of metals on global DNA methylation among e-waste recyclers and a reference population. Methods: This study made use of biological samples and exposure data collected during the first round of a parent/larger GEO Health II study - a longitudinal study. One hundred (100) male e-waste workers and fifty-one (51) male non-e-waste workers serving as a reference population were recruited at baseline. The participants provided survey data and blood samples for measurements of concentrations of metals as well as DNA methylation analysis. The methylation levels of long interspersed nucleotide repetitive elements-1 (LINE-1) was measured by pyrosequencing bisulfite-converted DNA from whole blood as a proxy for global DNA methylation. Personal PM2.5 and PM10 were measured over a 4-hour work-shift using real-time particulate matter monitors incorporated into a backpack and worn by study participants (e-waste workers and reference population). The concentrations of selenium (Se), zinc (Zn), manganese (Mn), cadmium (Cd) and lead (Pb) were measured in blood using inductively coupled plasma mass spectrometry (ICPMS). Descriptive statistics were used to determine differences in participant’s characteristics. Multiple linear regression model with robust standard errors (SE) from ordinary least squares (OLS) was used to evaluate the associations between PM and metals exposure on the one hand and LINE-1 DNA methylation on the other hand. Further, corresponding interaction terms were incorporated into the regression model to determine possible modification effect of selected toxic metals (Cd and Pb) on DNA methylation caused by essential metals (Mn, Se and Zn) concentrations. Lastly, a further sensitivity analysis using different variants of the outcome model (robust and cross-fit partialing-out least absolute shrinkage and selection operator (LASSO) linear regression models) were performed to compare with the results of the OLS with robust SEs. Results: Personal median concentrations of PM2.5 and PM10 were significantly higher among the e-waste workers than the reference population (PM2.5: median (interquartile range) 77.32(34.08) μg/m3 vs 34.88 (16.55) μg/m3, p < 0.001 and PM10: median (interquartile range) 210.21 (93.32) μg/m3 vs 121.92 (82.93) μg/m3, p < 0.001, respectively). Overall, metals (Cd, Mn, and Se) were significantly higher in the reference group (geometric mean: Cd = 0.8μg/L, Mn = 14.7 μg/L, and Se = 190.5 μg/L) than those in the e-waste worker group (geometric mean: Cd = 0.6 μg/L, Mn = 11.4 μg/L, and Se = 147 μg/L). Only Pb was significantly higher in the e-waste workers (geometric mean: Pb = 79.6 μg/L) compared to the reference group (geometric mean: Pb = 37.7 μg/L). There was no significant difference in LINE-1 methylation among the e-waste workers and the reference group (85.16 ± 1.32% vs 85.17 ± 1.11%, p=0.950). In the linear regression models controlling for confounders, the associations between PM2.5 and PM10, and LINE-1 DNA methylation were not statistically significant among the e- waste workers (βPM2.5 = 0.004; 95% CI; -0.001, 0.010, p = 0.114), and (βPM10 = 0.002; 95% CI; -0.001, 0.005, p = 0.088), respectively and reference population. For metals exposure, the OLS results of multiple metals showed a significant inverse association between Zn and the LINE- 1 DNA methylation among only the e-waste workers (βZn = -1.180, 95% CI: -2.199, -0.161, p = 0.024) which corresponds to a 0.012 decrease in LINE-1 DNA methylation (95% CI: -0.022, -0.002, p = 0.024) for a 1% increase in Zn concentration. The linear regression results from OLS with robust SEs and those of the sensitivity analysis yielded similar estimates of the beta- coefficients. Potential interactions between toxic and essential metals on global DNA methylation were observed. Conclusion: In conclusion, the high concentration of breathing zone PM and the body burden of metals detected in both the e-waste workers and reference population in Ghana shows the elevated levels of air pollutants in urban Ghana, particularly the capital city, Accra. Overall, PM concentration did not show significant association with LINE-1 DNA methylation in both the e-waste workers and the reference population. However, for metals exposure, increased blood zinc levels showed a significant decrease in LINE-1 methylation only among the e-waste workers. The results of this study further revealed that alteration of DNA methylation by toxic metals could be modified due to the concentration of essential metals. The alteration of LINE- 1 methylation by metals could serve as an early epigenetic marker for future adverse health outcomes in e-waste workers and other workers with similar exposure. Therefore, effective interventions to improve occupational safety for e-waste recycling workers are urgently needed.Item Influence Of Temperature On The Growth, Development And Susceptibility Of Anopheles Gambiae (S.L.) Mosquitoes To Pyrethroids(University Of Ghana, 2023-02) Agyekum, T.P.Background: Anopheles mosquitoes are responsible for transmitting malaria and lymphatic filariasis. They are among the notable vector species for their crucial role in transmitting malaria. The survival of the vector is of great interest as it affects its ability to transmit diseases. The biology and ecology of mosquitoes are strongly dependent on ambient temperature. The mosquito's life cycle includes four stages: egg, larva, pupa and adult. Indeed, the rearing temperature of the immature stages (egg, larva, and pupa) can significantly impact the completion of the life cycle, the overall fitness of the adult, and ability to transmit disease. In recent years, global warming and possible future warmer climate have prompted many studies to focus on the effects of elevated temperatures on both the morphology and the biology of various species, including vectors. Despite the importance of temperature variability on An. gambiae (s.l.) mosquito's development and survival, there is still the need to explore how and whether or not elevated temperatures associated with climate change is likely to reduce or increase the vector's population dynamics by modifying the life cycle, reduce the efficacy of insecticides, and increase the expression of metabolic enzymes in An. gambiae (s.l.) mosquitoes. Objective: This study aimed to investigate the influence of elevated temperatures on the growth and development of An. gambiae (s.l.) mosquitoes, and the effectiveness of pyrethroid insecticides in such higher temperatures. Methods: Anopheles gambiae (s.l.) eggs were obtained from colonies established in the laboratory and were incubated, hatched and reared under eight temperature regimes (25, 28, 30, 32, 34, 36, 38 and 40 °C) using climate-controlled incubators (RTOP-1000D, Zhejiang, China), with photoperiod of 12:12 (L:D) and 80 ± 10% relative humidity. Larvae were fed 10 mg of TetraFin goldfish flakes (Tetra Werke, Melle, Germany). All adults were fed with a 10% sugar solution soaked in cotton wool. In addition, female mosquitoes used to estimate fecundity and longevity were blood-fed using a guinea pig on day four (4) post-emergence. Larvae were monitored daily for development to the next stage. The time to pupation, pupation success, number of adults produced, and sex ratio of the newly emerged adult was recorded. Molecular identification of An. gambiae (s.l.) mosquitoes was done using polymerase chain reaction (PCR) to identify the composition of sibling species in the An. gambiae complex. Larval survival and adult longevity were monitored every 24 hours, and data were analyzed using Kaplan-Meier survival analysis. Furthermore, analysis of variance (ANOVA) was used to assess the relationship between temperature and development time, time to pupation, length of the gonotrophic cycle, biting rate and fecundity. Kruskal-Wallis test was also used to assess the relationship between temperature and pupation success, pupal mortality, the number of adults produced, and sex ratio. Digital images of larvae, pupae, adult wings and proboscis were captured using stereo microscope with inbuilt camera (Leica EZ4 HD, Leica Microsystems Limited, Switzerland) and body parts were measured using Leica Application Software, version 3.4.0 (Leica Microsystems Limited, Switzerland). Data on larval, and pupal weight and size, adult weight, size and proboscis length were log-transformed and analyzed using ordinary least square (OLS) regression with robust standard errors. In addition, three to five-day-old non-blood-fed An. gambiae (s.l.) mosquitoes were used for insecticide susceptibility test following the WHO bioassay protocol. Batches of 20 – 25 non-blood-fed female adult An. gambiae (s.l.) mosquitoes from each temperature regime (25 – 32 °C) were exposed to two pyrethroid insecticides (0.75% permethrin and 0.05% deltamethrin). The knockdown rate after 60 min and mortality at 24 h were recorded. The levels of four metabolic enzymes (MFO, GST, α-EST and β-EST) were examined in both mosquitoes that were not exposed and those exposed to pyrethroids. Results: An. gambiae (s.l.) mosquitoes used in this study consisted of An. gambiae (s.s.) and An. coluzzii. Development time of immature mosquitoes significantly decreased (F(5, 24) = 133.55, P < 0.001) with increasing temperature. Log-rank test showed that larval survival (X2(6) = 5353.12, P < 0.001) decreased with increasing temperature. In addition, Kruskal- Wallis test showed that the number of adults produced (X2(5) = 28.16, P < 0.001) decreased with increasing temperature, with male mosquitoes disproportionately produced at higher temperatures than females. Larval (βlarval size = 0.11, 95% CI; 0.14, 0.09, P < 0.001) and pupal (βpupal size = 0.12, 95% CI; 0.14, 0.10, P < 0.001) size significantly decreased with increasing temperature. Furthermore, longevity of both blood-fed (log-rank test; X2(4) = 904.15, P < 0.001) and non-blood-fed (log-rank test; X2(4) = 1163.60, P < 0.001) mosquitoes decreased with increasing temperature. The results further showed that the fecundity of mosquitoes significantly (F(2,57) = 3.46, P = 0.038) reduced with increasing temperature. Body size and proboscis length also decreased with increasing temperature. The mortality of An. gambiae (s.l.) mosquitoes to pyrethroids decreased at temperatures above 28 oC. Mosquitoes reared at higher temperatures were more resistant to the insecticides tested (deltamethrin and permethrin) and had more elevated enzyme levels than those reared at low temperatures (P < 0.05). Conclusion: Mosquitoes could not breed beyond temperatures at 36 oC. Therefore, if the ambient environmental temperatures rise to 36 oC, possibly as a consequence of climate change, it is likely to reduce or inhibit malaria transmission and perhaps its eradication in a future warmer temperature. In conclusion, warmer temperature is potentially hostile to a considerable proportion of emerging mosquitoes and may inhibit their survival such that the numbers of potential vectors may decrease. This study contributes to the knowledge on the relationship between temperature and growth and development of An. gambiae (s.l.) mosquitoes and provides helpful information for modelling vector population dynamics in a future warmer climate.Item Evaluation Of Ergonomic Risk Factors and Work-Related Musculoskeletal Disorders Associated with Informal Electronic Waste Recycling at Agbogbloshie in Accra, Ghana(University of Ghana, 2020-07) Acquah, A.A.Generation of electronic waste (e-waste) is a worldwide problem due to an ever-increasing global demand for new electronic appliances, and high turnover in replacing old and obsolete electrical and electronic appliances. Agbogbloshie, an informal e-waste processing site in Accra, Ghana is one of the largest of its kind in the world. The management and recycling of e-waste in an environmentally and occupationally safe and sustainable manner is a major challenge resulting in workers developing multiple health conditions. In addition, e-waste workers are also exposed to several physical risks due to the rudimentary methods of recycling which are known pathways to developing musculoskeletal disorders (MSDs). Notwithstanding, studies on adverse health effects of e-waste recycling have focused primarily on chemical exposures with little attention to physical exposures. Physical ergonomic exposures associated with informal e-waste recycling by lowwage, low-skilled workers are poorly understood. Further, current ergonomic assessment tools are intended for well-structured work environments. Ergonomic assessment tools to determine the physical exposures in unstructured and unregulated work settings such as e-waste recycling are lacking. The aim of this thesis, therefore, was to quantify the ergonomic risk factors and work-related MSDs associated with informal e-waste recycling at Agbogbloshie. Clearly defined specific objectives led to studies that allowed for the development of an observation-based exposure assessment tool adapted to unregulated and unstructured work in an informal sector. The studies were conducted at the e-waste site in Agbogbloshie, Accra Ghana. A reference population was recruited from Madina Zongo in Accra for comparison of work-related musculoskeletal disorders with e-waste workers. Participants in this thesis were conveniently sampled due to the informal and unstructured nature of the study sites. Direct field observations and in-depth interviews of eight e-waste workers were first conducted to better understand the processes and challenges associated with e-waste recycling. The obtained data were manually transcribed and coded into themes for analysis. Subsequently, a cross-sectional survey of 163 male e-waste workers complemented with direct field observations and pedometers was used to quantify workers’ occupational physical activities over a work week. The Occupational Physical Activity Questionnaire was modified by the researcher for this purpose. The Cornell Musculoskeletal Discomfort Questionnaire was used to estimate the self-reported prevalence of MSDs in 11 specific body regions of 176 e-waste workers and 41 non-e-waste workers from the reference population. To quantify exposure to physical risk factors, an observation-based tool that satisfies ease-of-use criteria and adapted for unstructured work in developing countries was designed. This new tool was used in real-time to quantify intensity and duration of e-waste workers’ exposure to ergonomic risk factors. The job categories, sample size, and the respective number of observations were determined based on preliminary observations. Thus, 6 dismantlers, 6 burners, and 11collectors were observed for 8, 6, and 3 days, respectively. Qualitative and observational data were analysed using thematic analysis while quantitative data were analysed using descriptive and inferential statistics. Chi-squared tests for categorical variables and ANOVA for continuous variables were used to test for statistical differences among e-waste worker categories, namely, collectors, dismantlers and burners. Multiple regression was used to examine relationships between physical exposure variables and MSDs. Results addressing the specific objectives of this thesis were as follows: Thematic analysis showed that, e-waste recycling at Agbogbloshie, from collection and transport to sorting to dismantling to open air burning are done manually using crude methods that require the use of rudimentary tools and physical strength. Assessment of occupational physical activity revealed that, all three categories of e-waste workers performed frequent strenuous occupational activities which differed significantly by primary job category. In addition, a high prevalence of MSDs was reported among e-waste workers (89.2%) compared to the reference population (70.7), which was claimed to interfered with their ability to work. Lower back pain was predominant regardless of job category. The newly developed ergonomic assessment tool showed good inter-observer agreement (i.e., 89% to 100%) for most risk factors assessed. Results from using this tool indicated that, durations of severe trunk flexion were significantly higher for dismantlers and burners (98.3 ± 24.6 and 188.7 ± 25.4 minutes respectively) compared to collectors; while high forces were exerted over longer periods by collectors and dismantlers (228.3 ± 20.1 and 177.3 ± 20.4 minutes respectively). Highly repetitive movements (> 20 / min) were significantly higher for dismantlers and burners (186.9 ± 20.9 and 178.8 ± 22.5 minutes respectively) than collectors. Although contact stress was present in all jobs, vibration was predominant among dismantlers. In conclusion, e-waste workers at Agbogbloshie are exposed to prolonged durations and high intensities of multiple ergonomic risk factors that predisposes workers to MSDs. The thesis identifies the ergonomics risk factors that need to be prioritised in the development of locally adapted ergonomic interventions for the efficient recycling of e-waste and the reduction of health and safety risks posed by unregulated and unstructured work in developing countries. The observational tool developed demonstrates promise in addressing the need for ergonomic tools tailored to informal and unregulated manual work settings, but needs refining to improve the measurement effort and precision in the assessment of risk factors and MSDs.Item Peri-Urban Environment, Sanitation and Health - Associated Health Risks in Waste Handling in Prampram, Ghana(University of Ghana, 2017-10) Kretchy, J.The peri-urban community of Prampram is characterized by filthy and choked open drains, indiscriminate waste disposal and open defecation. Waste handlers engage in different types of activities such as sweeping, collection, transportation and disposal with little or no personal protection and thus are often confronted with serious public health problems related to their work. The purpose for this study was to assess the different degrees of health risks associated with different activities in waste handling in the peri-urban community of Prampram, Ghana. This study used a mixed method design to quantitatively investigate 280 waste handlers with respect to the activities performed, exposure surfaces to waste, use of personal protective working gear and self reported health outcomes. A qualitative phase of the study involving 22 waste handlers explored the perceptions about health risks associated with waste work. The rationale 'or including the qualitative phase was to triangulate and complement the quantitative phase of the study. Laboratory methods were also used to investigate faecal contamination of hands by the detection of faecal indicator E. coli/Coliforms as well as to determine the incidence rate and intensity of helminthes infections 3 and 6 months post-treatment. The most common self-reported health problems were bodily pains (56.4%), headache (38.6%), fever (35.7%) and diarrhoea (11.4%). There was an association between working with smelling/odorous waste material and reported fever (p < 0.05) as well as contact of exposed bodily surfaces to waste with reported skin disease (p < 0.05). The perception about reporting health problems due to working with smelling waste material was corroborated by one 35-years old female waste handler who collected human faeces from the beach each morning when she explained how inhalation of 'bad air' could lead to health problems such as nausea. Waste handlers whose hands were directly exposed to waste material were 4.2 times (95%CI: AOR 1.4-10.0) more probable to report cough symptoms than those whose hands were not exposed. The odds of reporting upper back pain among waste handlers who performed three activities a day (sweeping, collection and disposal) was 4.1 times (95%CI AOR: 1.6-11.0) greater than those who only swept every day. Waste handlers who swept every day have 70% less risk of developing upper back pain compared to those who performed two activities per day (disposal and collection). The odds of reporting upper back pain was 2.2 times (95%CI AOR: 0.6-8.0) higher among those who transport waste compared to those who sweep. There was a significant difference (p < 0.0001) in the level of faecal contamination of the hands of waste handlers before and after engaging in waste handling activities, by detection of both indicator E. coli and Coliforms. The proportion of waste handlers that tested positive to faecal indicator E. coli was 23.2% (95%CI: 18.4-28.8) The mean log concentrations/level of indicator E. coli among waste handlers was 0.079 ± 1.6 CFUl50ml. There was also a significant difference (x2 = 18.8, p = 0.0086) in the mean log concentration/level of faecal indicator E. coli among the types of waste handling activities. There was a significant difference (p = 0.0083) in the level of faecal indicator E. coli among waste handlers who only engaged in sweeping every day and those who performed two or more waste management activities such as sweeping, collection and disposal. Helminthes infections among waste handlers correlated with the type of waste handling activities based on the likelihood ratio Chi-square test statistic (LR=IS.3, p = 0.033). The mean intensity of helminthes infection among waste handlers 6 months post-treatment with Albendazole (400mg) single oral dosage was 2.8 egg/gram, indicating light intensity whilst the incidence rate of helminthes infections was 1.46% per month. The proportion of waste handlers who experienced light intensity helminthes infection was 4.3% after 6 months post-treatment. Waste handlers who used rubber gloves during work were 80% less likely to acquire helminthes infections compared with those who did not use gloves. The detection of faecal indicator E. coli on hands of waste handlers was corelated with helminthes infections (p < 0.0001) and nine waste handlers (3.2%) tested positive for both indicator E. coli and helminthes. There is an increasing number of waste handlers in the peri-urban community of Prampram engaged in different types of waste handling activities, who also belong to different waste management organizations. These waste handlers have different levels of exposures to waste and reported with different degrees of health outcomes. It was clearly demonstrated by this study that using bare hands to perform waste handling activities increases the likelihood of reported health problems, contamination of hands by faecal material and infection with Trichiuris trichiura. Thus waste handlers experience a burden of disease which is likely to be consequences of their occupation. Private companies and government institutions employing waste handlers in the peri-urban community of Prampram must ensure periodic anti-helminthic treatment of waste handlers (at least every 6 months), provide adequate hand washing and hygiene facilities (soap and water) as well as suitable and affordable personal protective working gear to waste handlers and supervise their use during work.Item The Role of Genetic and Epigenetic Factors in Endothelial Damage and Repair among Ghanaian Children with Cerebral Malaria(University of Ghana, 2019-03) Amoako-Sakyi, D.The declining malaria burden in endemic regions is predicted to increase the proportion of malaria infections that progress to cerebral malaria (CM). This epidemiologic scenario appears ominous against the backdrop of a poor understanding of CM pathogenesis, lack of effective adjunctive therapies, and poor prognosis after onset. Thus, the need to better understand the pathogenesis of CM has become more apparent. To better understand the pathogenesis of CM, this study explored both genetic and epigenetic aspects of the emerging malaria pathophysiologic paradigm, which pivots on imbalances in endothelial damage and repair in cerebral microvasculature during P. falciparum infections. The Sequenom MassARRA Y platform (iPLEX) was used to genotype a focused panel of 27 single nucleotide polymorphisms (SNPs) in a cross-sectional study involving 221 children. In silico techniques were used to characterize the epigenetic context of SNPs and assess their potential effect on microRNAs and transcription factors. Immune cells and angiogenic factors were measured with Human Magnetic Luminex Assay and flow cytometry, respectively. A striking find of this study was the association of a CDH5 SNP (rs2304527) and an MMP9 SNP (rs3918256) with CM and endothelial integrity respectively. CDH5 SNP (rs2304527) offered protection from CM under the over-dominant inheritance model assumption and children with the heterozygote T/G genotype were approximately three times less likely to have CM relative to their colleagues with the IT -GG genotype. On the other hand, MMP9 SNP (rs3918256) was a risk factor for endothelial damage. Relative to the reference genotype (GG), children with the AA genotype ofrs3918256 were approximately 4 times more likely to be classified as ProDamage under the recessive inheritance model. These two SNPs were subsequently found to disrupt the binding sites of several transcription factors involved in the angiopoietin and tie signalling pathway. Several other SNPs were found to influence the binding affinity of transcription factors but only two (rs3918211 and rs20544) affected micro RNA target sites. Receiver operating characteristic (ROC) analysis to test the ability of angiogenic factors to discriminate between malaria and endothelial integrity phenotypes gave middling results. The best performing angiogenic factor for discriminating eM from UM was NGRI which had only a 66% chance of accurately discriminating eM from UM. Similarly, all angiogenic factors performed poorly in discriminating endothelial integrity phenotypes. This is the first study to implicate rs2304527 and rs3918256 in the pathogenesis of eM. Although in silico analysis suggests some epigenetic roles for these SNPs, future studies may want to further explore their functional roles. Unfortunately, the prospects of using angiogenic factors considered in this study to discriminate between malaria and endothelial integrity phenotypes appear dim. Taken together, this study provides valuable insights on the genetic and epigenetic aspects of endothelial damage and repair during a P. falciparum malaria in Ghanaian children.Item Peri-Urban Environment, Sanitation and Health -Associated Health Risks in Waste Handling in Prampram, Ghana(University of Ghana, 2017-10) Kretchy, J.The peri-urban community of Prampram is characterized by filthy and choked open drains, indiscriminate waste disposal and open defecation. Waste handlers engage in different types of activities such as sweeping, collection, transportation and disposal with little or no personal protection and thus are often confronted with serious public health problems related to their work. The purpose for this study was to assess the different degrees of health risks associated with different activities in waste handling in the peri-urban community of Prampram, Ghana. This study used a mixed method design to quantitatively investigate 280 waste handlers with respect to the activities performed, exposure surfaces to waste, use of personal protective working gear and self reported health outcomes. A qualitative phase of the study involving 22 waste handlers explored the perceptions about health risks associated with waste work. The rationale 'or including the qualitative phase was to triangulate and complement the quantitative phase of the study. Laboratory methods were also used to investigate faecal contamination of hands by the detection of faecal indicator E. coli/Coliforms as well as to determine the incidence rate and intensity of helminthes infections 3 and 6 months post-treatment. The most common self-reported health problems were bodily pains (56.4%), headache (38.6%), fever (35.7%) and diarrhoea (I1.4%). There was an association between working with smelling/odorous waste material and reported fever (p < 0.05) as well as contact of exposed bodily surfaces to waste with reported skin disease (p < 0.05). The perception about reporting health problems due to working with smelling waste material was corroborated by one 3S-years old female waste handler who collected human faeces from the beach each morning when she explained how inhalation of 'bad air' could lead to health problems such as nausea. Waste handlers whose hands were directly exposed to waste material were 4.2 times (9So/oCI: AOR 1.4-10.0) more probable to report cough symptoms than those whose hands were not exposed. The odds of reporting upper back pain among waste handlers who performed three activities a day (sweeping, collection and disposal) was 4.1 times (95%CI AOR: 1.6-11.0) greater than those who only swept every day. Waste handlers who swept every day have 70% less risk of developing upper back pain compared to those who performed two activities per day (disposal and collection). The odds of reporting upper back pain was 2.2 times (95%CI AOR: 0.6-8.0) higher among those who transport waste compared to those who sweep. There was a significant difference (p < 0.0001) in the level of faecal contamination of the hands of waste handlers before and after engaging in waste handling activities, by detection of both indicator E. coli and Colifonns. The proportion of waste handlers that tested positive to faecal indicator E. coli was 23.2% (950/oCl: 18.4-28.8) The mean log concentrations/level of indicator E. coli among waste handlers was 0.079 ± 1.6 CFUl50ml. There was also a significant difference (.J! = 18.8, p = 0.0086) in the mean log concentration/level of faecal indicator E. coli among the types of waste handling activities. There was a significant difference (p = 0.0083) in the level of faecal indicator E. coli among waste handlers who only engaged in sweeping every day and those who performed two or more waste management activities such as sweeping, collection and disposal. University of Ghana http://ugspace.ug.edu.gh Helminthes infections among waste handlers correlated with the type of waste handling activities based on the likelihood ratio Chi-square test statistic (LR=IS.3, p = 0.033). The mean intensity of helminthes infection among waste handlers 6 months post-treatment with Albendazole (400mg) single oral dosage was 2.8 egg/gram, indicating light intensity whilst the incidence rate of helminthes infections was 1.46% per month. The proportion of waste handlers who experienced light intensity hdminthes infection was 4.3% after 6 months post-treatment. Waste handlers who used rubber gloves during work were 80% less likely to acquire helminthes infections compared with those who did not use gloves. The detection of faecal indicator E. coli on hands of waste handlers was corelated with helminthes infections (p < 0.0001) and nine waste handlers (3.2%) tested positive for both indicator E. coli and helminthes. There is an increasing number of waste handlers in the peri-urban community of Prampram engaged in different types of waste handling activities, who also belong to different waste management organizations. These waste handlers have different levels of exposures to waste and reported with different degrees of health outcomes. It was clearly demonstrated by this study that using bare hands to perform waste handling activities increases the likelihood of reported health problems, contamination of hands by faecal material and infection with Trichiuris trichiura. Thus waste handlers experience a burden of disease which is likely to be consequences of their occupation. Private companies and government institutions employing waste handlers in the peri-urban community of Prampram must ensure periodic anti-helminthic treatment of waste handlers (at least every 6 months), provide adequate hand washing and hygiene facilities (soap and water) as well as suitable and affordable personal protective working gear to waste handlers and supervise their use during work.Item Establishing Reference Intervals or Haematological, Biochemical, and Immunological Analytes among Urban Ghanaian Adult Population(University of Ghana, 2019-07) Bawua, S. A.Background Reference intervals (RIs) refer to the upper and lower reference limits of laboratory test derived from healthy individuals recruited with well-defined criteria. RI serves as a comparison tool and an important determinant of whether an individual is healthy or not, which apparently remains the most extensively used decision-making tool in clinical settings. Considering the importance of RIs for the interpretation of laboratory test, the International Federation of Clinical Chemistry (IFCC) has recommended that each laboratory obtains its own reference values and estimate the corresponding RIs within defined procedures. Even though the recommendation from IFCC/Clinical laboratory standard institute (CLSI) is required, yet majority of diagnostic laboratories in Ghana are unable to implement their own RIs due to the cost and challenges involved in recruiting the reference population. For that reason, the majority of laboratories work with reference intervals that are based on guidelines developed by manufacturers of analyzers. Thus, the continual use of such existing RIs from different manufacturer analyzers affects clinical decision making and might lead wrong interpretation of laboratory results, which is a public health concern. Aim This study aimed to establish reference intervals for haematological, biochemical and immunological analytes that would inform context-specific clinical decision-making and interpretation of laboratory results for healthcare practice in Ghana. Methods In a cross-sectional study design; healthy individuals, aged 18 – 60+ years were recruited using a simple random sampling technique. A total of 501 apparently healthy subjects; from the Tamale and Accra Metropolis which are capital cities of the Northern and Greater Accra region respectively were recruited into the study. Structured questionnaires were administered to volunteers to collect data on demographics, lifestyles, dietary pattern and their clinical information. The selection of eligible participants was primarily based on well-defined inclusion and exclusion criteria, which were in accordance with the IFCC/C-RIDL protocol. A fasting blood sample of 24mL was drawn into two plastic evacuated tubes containing ethylene diamine tetra-acetic acid (EDTA), three serum separate tube (SST), one sodium fluoride (NaFl) tube and one lithium heparin tube for complete blood count (CBC) and clinical chemistry analysis. Whole blood samples were analyzed using Sysmex XN 1000 analyzer for haematology analytes while the clinical chemistry, immunoglobulin, hormones, and tumour marker analytes were analyzed using Beckman Coulter AU 480 analyzer, Roche Cobas e411 analyser and Centaur XP Siemens’ analyzer respectively. All laboratory investigations were carried out in accordance with the laboratory’s standard operating procedures (SOPs). Stata version 13 software (Stata Corp., College Station, Texas, United States) was used in analyzing the data. Multiple regression analysis was performed to determine the relationship between variables. Partitioning of reference values by sex and age was done by the computing standard deviation ratio (SDR) using 3-level nested ANOVA by StatFlex version 6.0 statistical software (Artech Inc., Osaka, Japan). Prior to the derivation of the RIs, the latent abnormal values exclusion (LAVE) method was conducted to exclude individuals with such latent diseases. The latent abnormal values exclusion (LAVE) method is a secondary exclusion procedure applied to refine the data. Using “Reference interval Master” software, RIs of each analyte were derived using the parametric method. Results The participants’ mean age was 41.3 ± 13.5 years. RIs derived for major analytes were haemoglobin (males=12.8 - 17.2; females=10.7 - 14.3 g/dL), haematocrit (39.4 - 52.1; 34.0 - 44.2%), platelet (male 115–339; female 157–402 ×1010/L), uric acid (males=231- 487; females=149 – 377Umol/L), GGT (male = 17-87 IU/L; female = 12-49 IU/L). SDR ≥ 0.4 was used as a critical value for the partitioning of RVs by sex for all erythrocyte parameters (RBC, Hb, Ht, Fe, Ferr) and platelet counts. No sex-related difference was observed in any leukocyte parameter except eosinophil counts. Again, with clinical chemistry analytes’ sex variation was observed in Ca, CK, UA, Tbil, Dbil, AST, ALT, GGT, Cre, Cl, IgM, Fe, Ferr, CA125 and the hormone analytes as their SDR ≥ 0.4. Also, age-related changes with SDR ≥ 0.4 was noted only for RBC in males for haematology analytes. Application of LAVE had a conspicuous effect on RIs for the majority of erythrocyte parameters as well as folate, Fe, Ferr, CRP, LDL-C, TG, TC, CK, Glu, AST, ALT, and GGT. Some of the RIs for Ghanaian adults are RBC (male = 4.57–6.50×1012/L; female = 4.00–5.46 ×1012/L), Hb (male =12.8–17.2 g/dL; female=10.7–14.3 g/dL), eosinophils (male =0.5–10.3%; male= 0.4–6.5%), CK (male = 93-502U/L; female 52 -276 U/L) and amylase (male= 42 – 177 Umol/L; female = 43-158 Umol/L). Conclusion The findings from the present study therefore, indicate that adopting these haematological and clinical chemistry RIs for clinical use will be beneficial to healthcare systems in Ghana since most of the RIs derived were significantly different from the ones currently in use. Sex, age and BMI related differences were mainly the sole determinants of variations among most analytes. This indicates that sex and age-specific RIs are required for the effective interpretation of some haematological and clinical chemistry analytes. The robust statistical technique used in this study makes the RI derived more reliable for clinical decision making and patient care in the country.Item A Study of Solid Medical Waste at the Community Level: Generation and Collection in Households, among Traditional Birth Attendants and Chemical Shop Vendors, and Impacts on Health(University of Ghana, 2016-03) Udofia, E.A.; Fobil, J.N.; Gulis, G.; University of Ghana, College of Health Sciences, School of Public Health, Department of Biological, Environmental and Occupational HealthBackground: Solid waste generated from activities involving health protection, medical diagnosis and treatment, known as solid medical waste (SMW), is increasing in households due to home based care, treatment of chronic diseases, shortened lengths of hospital stay, and home management of illnesses such as malaria. The hazardous properties of SMW require specific management to minimize potential harm to human health and the environment, which is often undertaken in healthcare facilities. However, little is known about the characteristics and management of SMW from non-traditional settings in the community. Objective: To investigate the management of solid medical waste in a district in the Greater Accra Region of Ghana, focusing on households, traditional birth attendants (TBAs) and chemical shop vendors (CSVs). Methods: A descriptive, exploratory, mixed methods study, comprising a 3-staged study design was conducted in Ga South Municipal Assembly. The first stage explored collection, disposal, and harm from SMW in 600 households using questionnaires followed by interviews with private waste contractors and focus group discussions (FGDs) with adult members of households. In the second stage, household solid waste (HSW) was collected in dry and wet seasons from 60 households and manually segregated to obtain the SMW components. These were weighed and percentage composition calculated. The third stage explored stakeholder perspectives regarding segregation of SMW at source as a management option, using FGDs. Seasonal differences and relationships with SMW generation were evaluated, while qualitative data were analyzed using a thematic approach. Results: Household production and per capita generation of SMW were 7.26 x 10-3kg/household/day and 1.77 x 10-3kg/person/day respectively. Medicinal waste and sharp waste comprised 98% and 2% of SMW respectively. Daily per capita generation of SMW was significantly higher in the wet season than in the dry season (z = 3.129, p = 0.002). Harm due to SMW was reported by 4.8% of households and mostly involved sharps. Barriers to segregation of SMW at source included lack of community education, storage facilities and logistics, time consumption and cost. Conclusion: Although the quantity of SMW in HSW is low, its composition, largely of medicinal waste, and a smaller proportion of sharps conferred on it some hazardous properties. Community education and logistic support for segregation at source might improve SMW management in the community.