Institute of Environmental Management and Quality Control
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Item Prevalence of Acute Respiratory Infections in Women and Children in Western Sierra Leone due to Smoke from Wood and Charcoal Stoves(Multidisciplinary Digital Publishing Institute, 2012-06-19) Taylor, Eldred TundeCombustion of biomass fuels (wood and charcoal) for cooking releases smoke that contains health damaging pollutants. Women and children are the most affected. Exposure to biomass smoke is associated with acute respiratory infections (ARI). This study investigated the prevalence of ARI potentially caused by smoke from wood and charcoal stoves in Western Sierra Leone, as these two fuels are the predominant fuel types used for cooking. A cross sectional study was conducted for 520 women age 15-45 years; and 520 children under 5 years of age in homes that burn wood and charcoal. A questionnaire assessing demographic, household and exposure characteristics and ARI was administered to every woman who further gave information for the child. Suspended particulate matter (SPM) was continuously monitored in fifteen homes. ARI prevalence revealed 32% and 24% for women, 64% and 44% for children in homes with wood and charcoal stoves, respectively. After adjusting for potential confounders for each group, the odds ratio of having suffered from ARI was similar for women, but remained large for children in homes with wood stoves relative to charcoal stoves (OR = 1.14, 95%CI: 0.71-1.82) and (OR = 2.03, 95%CI: 1.31-3.13), respectively. ARI prevalence was higher for children in homes with wood stoves compared with homes with charcoal stoves, but ARI prevalence for both types of fuels is higher compared with reported prevalence elsewhere. To achieve a reduction in ARI would require switching from wood and charcoal to cleaner fuels.Item Leapfrog diagnostics: Demonstration of a broad spectrum pathogen identification platform in a resource-limited setting(BioMed Central, 2012-07-04) Łęski, Tomasz A.BACKGROUND: Resource-limited tropical countries are home to numerous infectious pathogens of both human and zoonotic origin. A capability for early detection to allow rapid outbreak containment and prevent spread to non-endemic regions is severely impaired by inadequate diagnostic laboratory capacity, the absence of a "cold chain" and the lack of highly trained personnel. Building up detection capacity in these countries by direct replication of the systems existing in developed countries is not a feasible approach and instead requires "leapfrogging" to the deployment of the newest diagnostic systems that do not have the infrastructure requirements of systems used in developed countries. METHODS: A laboratory for molecular diagnostics of infectious agents was established in Bo, Sierra Leone with a hybrid solar/diesel/battery system to ensure stable power supply and a satellite modem to enable efficient communication. An array of room temperature stabilization and refrigeration technologies for reliable transport and storage of reagents and biological samples were also tested to ensure sustainable laboratory supplies for diagnostic assays. RESULTS: The laboratory demonstrated its operational proficiency by conducting an investigation of a suspected avian influenza outbreak at a commercial poultry farm at Bo using broad range resequencing microarrays and real time RT-PCR. The results of the investigation excluded influenza viruses as a possible cause of the outbreak and indicated a link between the outbreak and the presence of Klebsiella pneumoniae. CONCLUSIONS: This study demonstrated that by application of a carefully selected set of technologies and sufficient personnel training, it is feasible to deploy and effectively use a broad-range infectious pathogen detection technology in a severely resource-limited setting.Item Considerations in the selection of healthcare providers for mothers and children in Bo, Sierra Leone: reputation, cost and location(Oxford University Press, 2012-10-30) Jacobsen, Kathryn H.The factors that influence the selection of a healthcare provider once the decision to seek care has been made can be summarized using a triad of cost, location and reputation. The goal of this study was to identify which of these factors is the primary consideration when women in urban Bo, Sierra Leone, select a healthcare provider for themselves or their children. We interviewed 1091 mothers during a household census of two neighbourhoods of Bo in April 2010. Reputation was the top consideration for about half of the women, cost was the second most common priority, and the location of the healthcare facility was the primary consideration for less than 7% of the participants. The majority of women said they would select a new provider if cost was not a barrier. Socioeconomic characteristics were not significant predictors of whether cost, location or reputation was selected as the highest-ranked consideration. This evidence for the importance of reputation in healthcare decision-making even in low-resource areas highlights the need for health systems to address issues of quality and responsiveness, and not just cost, in order to increase access to and utilization of health services.Item Identification of bla OXA-51-like , bla OXA-58 , bla DIM-1 , and bla VIM Carbapenemase Genes in Hospital Enterobacteriaceae Isolates from Sierra Leone(American Society for Microbiology, 2013-05-09) Łęski, Tomasz A.We describe the results of a molecular epidemiological survey of 15 carbapenemase-encoding genes from a recent collection of clinical isolates from Mercy Hospital in Bo, Sierra Leone. The most salient findings revealed that (i) 60% of the isolates harbored multiple carbapenemase genes; (ii) the blaDIM-1 gene, which has previously only been reported in The Netherlands, is also circulating in this environment; and (iii) blaOXA-51-like and blaOXA-58 genes, which were thought to reside exclusively in Acinetobacter species, can also be found in members of the Enterobacteriaceae.Item Characterization and Determination of PM2.5 Bound Polycyclic Aromatic Hydrocarbons (PAHS) in Indoor and Outdoor Air in Western Sierra Leone(OMICS Publishing Group, 2015) MJ, Taylor ET WirmvemEleven airborne PM2.5 PAH concentrations were characterized in the kitchen, outdoor and living room environments in households that burn wood and charcoal fuels in Western Sierra Leone, during a survey that was conducted in September 2011. The average concentration of total PAHs (Σ11PAHs) was 1279.7 ng/m3 in kitchen, 41.2 ng/m3 in outdoor, 19.8 ng/m3 in living room for households burning wood while those burning charcoal was 96.5 ng/m3, 13.1 ng/ m3 and 8.9 ng/m3 in the kitchen, outdoor and living room, respectively. The percentage contribution of higher molecular weight PAHs to Σ11PAHs was about 25% higher compared to medium molecular weight PAHs for either household category in all three locations, with a somewhat different scenario for kitchens with wood stove. The ratio of indoor/ outdoor air of Σ11PAHs showed considerable variation among households burning charcoal (p=0.0021; t-test) relative to those burning wood, attributed to non-prolonged equilibrium between the two environments. Benzo(a)pyrene (BaP) equivalency results revealed that BaP and dibenzo(a,h)anthracene were the two most dominant compounds that contributed to more than 90% of the total carcinogenicity in all three environments for households burning wood and charcoal. The results suggest that kitchens, where biomass fuels are burnt continue to be a hazardous place for people of developing countries to spend their time.Item Variation in stable isotope ratios of monthly rainfall in the Douala and Yaounde cities, Cameroon: local meteoric lines and relationship to regional precipitation cycle(Springer Nature, 2016-04-16) Wirmvem, Mengnjo JudeHydrogen (D) and oxygen (18O) stable isotopes in precipitation are useful tools in groundwater recharge and climatological investigations. This study investigated the isotopes in rainfall during the 2013 and 2014 hydrological years in the Douala and Yaounde urban cities. The objectives were to generate local meteoric water lines (LMWLs), define the spatial–temporal variations of the isotopes in rainwater and their relationship to the regional precipitation cycle, and determine the factors controlling the isotopic variation. The LWMLs in Douala and Yaounde were δD = 7.92δ18O + 12.99 and δD = 8.35δ18O + 15.29, respectively. The slopes indicate isotopic equilibrium conditions during rain formation and negligible evaporation effect during rainfall. Precipitation showed similar wide ranges in δ18O values from −5.26 to −0.75 ‰ in Douala and −5.8 to +1.81 ‰ in Yaounde suggesting a common moisture source from the Atlantic Ocean. Enriched weighted mean δ18O (wδ18O) values during the low pre- and post-monsoon showers coincided with low convective activity across the entire region. Enriched isotopic signatures also marked the West African monsoon transition phase during each hydrological year. Abrupt wδ18O depletion after the transition coincided with the monsoon onset in the region. Peak periods of monsoonal rainfall, associated with high convective activities, were characterised by the most depleted wδ18O values. Controls on isotopic variations are the amount effect and moisture recycling. The stable isotope data provide a tool for groundwater recharge studies while the isotopic correlation with regional rainfall cycle demonstrate their use as markers of moisture circulation and detecting climatic changes in precipitation.Item Prevalence of Quinolone Resistance in Enterobacteriaceae from Sierra Leone and the Detection of qnrB Pseudogenes and Modified LexA Binding Sites(American Society for Microbiology, 2016-08-30) Łęski, Tomasz A.A collection of 74 Enterobacteriaceae isolates found in Bo, Sierra Leone, were tested for quinolone antibiotic susceptibility and resistance mechanisms. The majority of isolates (62%) were resistant to quinolones, and 61% harbored chromosomal gyrA and/or parC mutations. Plasmid-mediated quinolone resistance genes were ubiquitous, with qnrB and aac(6')-Ib-cr being the most prevalent. Mutated LexA binding sites were found in all qnrB1 genes, and truncated qnrB pseudogenes were found in the majority of Citrobacter isolates.Item Lease of Noxious Gases During Burning of Mosquito Coils: A Pilot Study(2016) Beah, Joe MiltonIndoor air pollution due to combusting biomass fuels is a serious problem in developing countries and the impact to a greater extent is less known from burning mosquito coils. As malaria is a major killer in developing countries, the use of mosquito repellants would continue to be used in millions of homes across the continent of Africa. Hence this pilot study was conducted to assess emission levels of nitrogen dioxide (NO2); sulphur dioxide (SO2) and carbon monoxide (CO) during the burning of six different products of mosquito coils that are sold in Sierra Leone. One hour emission value was recorded for each product during the burning period. Result revealed that one hour SO2 concentrations range from not detected to 47 ppb and that for CO range from 16 ppm to 19 ppm for the different products. Evidence of high peak values was observed for both SO2 and CO for the different products which is clearly a public health concern. This pilot study demonstrated that burning mosquito coils in less ventilated rooms where the primary focus is to eliminate mosquitoes is an environmental health risk in Sierra Leone.Item Emission of Combustible Gases at Traffic and Practising Waste Dumpsite in Freetown, Sierra Leone: A Pilot Study(Scientific Research Publishing, 2016-12-07) Williams, Bunting KayodeAn assessment of the emission of combustible gases in developing countries requires reliable analytical realtime monitors that can rapidly screen them with minimal handling. Considering the expensive nature of monitoring environmental pollutants, chemical sensors are expected to play a pivotal role in measuring and recording environmental data. The Drager X am 5000 was used to report emission levels of combustible gases in this study, namely; nitrogen dioxide (NO2), sulphur dioxide (SO2) and carbon monoxide (CO) at traffic and practising waste dumpsite in Freetown, the main city of Sierra Leone. Hourly average values for the three pollutants were recorded in the morning, afternoon and evening periods, respectively. The range of values were 18 - 76 ppb for NO2, 211 - 506 ppb for SO2 and 11 - 14 ppm for CO at traffic site; and 6 - 16 ppb for NO2, 118 - 276 ppb for SO2 and 8 - 15 ppm for CO at the dumpsite, respectively. There were significantly high hourly variations for NO2 and SO2 at the traffic site and for CO and SO2 at the dumpsite. Evidence of peak values showed emission levels that were considered dangerous for human exposure. This pilot study revealed that combustible gases released in certain areas of the capital city are a concern for both public health officials and environmental advocates.Item Wastewater Effluents at Sierra Leone Bottling Company Limited: Composition, Assessment and Removal Efficiency of Physico-chemical Parameters(Science Publishing Group, 2017) Beah, Joe MiltonThe analyses of industrial effluents at Sierra Leone Bottling Company Limited (SLBC) in Freetown, the capital city of Sierra Leone were conducted to assess its composition, and removal efficiency of physico-chemical parameters. Fifteen (15) samples were collected from the drain water (influent), pre treatment effluent and treated effluent (effluent) for five days. There were significantly higher concentrations of influents parameters relative to those of the corresponding effluents. The influent levels for pH, electrical conductivity and chloride were higher than permissible threshold. 80% of the samples at the influent point were within permissible guideline for TDS but all were in total agreement with the effluent samples for the same parameter. Comparative analyses showed significant reduction in values for pH, temperature, iron and chromium in the effluent samples relative to the influent samples and all of the other parameters did not show any statistically significant differences. The treatment plant was noted to be highly efficient in removing iron and chromium but least efficient for total dissolved solids and water temperature. Huge variances with respect to removing contaminants for chloride, electrical conductivity and total dissolved solids were observed. The average overall removal efficiency of contaminants in industrial effluents was low but the practice of treating industrial wastewater by SLBC was plausible. Considering the pollution load of certain parameters being investigated, it is imperative for the SLBC to initiate the process of setting up waste stabilization ponds (WSP) so as to contain industrial effluents for further examination before they are discharged into the environment.