18 research outputs found

    Environmental impact of volcanic emissions at Nyiragongo (DRC)

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    The large amount of trace elements emitted from volcanoes has a strong impact on the close surrounding areas. Nyiragongo Volcano (Democratic Republic of Congo) belongs to the Virunga volcanic chain and is one of the most active volcanoes in Africa. It is characterized by the presence of an active and permanent lava lake with a persistent degassing activity. During a field trip in October-November 2014, we investigated the impact of the volcanogenic deposition in the surrounding of the crater by using different sampling techniques. Rain-gauges were used to collect atmospheric bulk deposition. Active and passive biomonitoring techniques (moss-bags and leaves of endemic plants – Senecio spp. and Amarantus viridis) were applied in order to investigate the dispersion of volcanic gas and particle emissions. We collected daily rainfall events at various sites: seven samples at the crater rim (on the western and southern side, 3470 m a.s.l.), one sample at the village Kibati (south-eastern flank, 1955 m a.s.l.) located at the up-wind base of the volcano (representing the local background), and four samples in the city of Goma (southern flank of the volcano, 1500 m a.s.l.). In order to implement our dataset, several samples of rainwater, amaranth leaves, soils and atmospheric depositions (by moss-bags and filters exposition) were sampled after the field trip by the researchers of the Goma Volcano Observatory (GVO). Since, the prevalent wind direction was blowing the plume in westerly or southwesterly direction, we exposed the raingauges in the villages of Bulengo, Rusayo and Kingi in the southwestern side respect to the volcano, and Kibumba in the southesthern as a background site, at increasing distance from the rim. In the same sites, leaves of Amarantus viridis, which is one of the principal vegetables eaten by the local population, were collected. Rainwater, moss bags and plant samples were analyzed for major and trace elements by IC, ICP-OES and ICP-MS. The large amount of emitted volcanic gases and particles includes sulfur, halogens and trace elements, that strongly affect rainwater chemistry and have a widespread impact on the surrounding vegetation of the volcano. Indeed, rainwater samples collected at the rim of the crater have low pH values (_ 3), high concentration of F- and Cl- (up to 12.0 and 12.8 mg/l, respectively) and dissolved toxic elements (such as Al, As, Cd, Cu, Fe and Pb), whereas samples from the city of Goma have pH values above 5 and the same elements show orders of magnitude lower concentrations. The biomonitoring results highlight that bioaccumulation of trace elements is extremely high in the proximity of the crater rim and decreases with the distance from the active craters. The data will be compared to earlier measurements taken in December 2011 and the impact of a slightly decreasing gas emission on the vegetation will be discussed

    Sorption of cadmium in columns of sand-supported hydrothermally carbonized particles

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    Sanitation in urban slums, especially in countries in Sub-Saharan Africa, is a challenge. One of the solutions to sanitation is to valorize waste, and to convert bio-waste present in the slum in a cheap and affordable way into lignite via hydrothermal carbonization (HTC). HTC is simple, cheap, converts all carbon (100%), eliminates pathogens completely, and requires wet starting products/biomass, thereby avoiding complicated drying schemes. In this research, we investigated the effectiveness of removing a divalent metal-ion, cadmium, using equilibrium batch experiments and columns of sand-supported hydrothermally carbonized colloidal lignite (HTCCL) derived from sugar, maize, and grass. Our results indicated that equilibrium sorption could be best described by a Langmuir isotherm. The uptake capacity varied from 0.11 to 0.21 mg Cd/g HTC, dependent on the type of HTC used. These values were relatively low compared to other carbonaceous sorbents. However, removal efficiencies in column experiments were remarkably high: 70–100% during 20–24 pore volumes or bed volumes of flushing. We concluded that HTCCL is a promising sorbent that can be used to treat heavily polluted water and/or wastewater.</jats:p

    Assessing the burden of Taenia solium cysticercosis in Burundi, 2020

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    Background. Taenia solium cysticercosis is a zoonotic disease that is endemic in many low- and middle-income countries where risk factors for disease transmission are present. The economic impact of cysticercosis on public health and on the pig production sector is not well known in many of those countries, including Burundi. This study aimed at estimating the burden of T. solium cysticercosis in Burundi including data on humans and&nbsp;pigs. Methods. Epidemiological and economic data were collected from literature up to July 30, 2021 and governmental and non-governmental agencies. Direct and indirect costs for neurocysticercosis (NCC)-associated epilepsy and losses due to porcine cysticercosis were estimated to assess the economic burden, while the health burden was estimated using zoonotic disability-adjusted life years (zDALYs). Different probability distributions (Uniform, Beta, Dirichlet and Gamma) were applied depending on the type of epidemiological parameter. Monte Carlo simulations and 100,000 iterations were used to calculate the 95% uncertainty interval (UI) for each parameter and perform sensitivity&nbsp;analyses. Results. In Burundi, 4.26 million USD (95% UI, 1,858,308–8,190,951) were estimated as economic impact due to T. solium cysticercosis in humans and pigs, of which 40.2% (95% UI, 10.3–75.1) of the total costs were due to NCC-associated epilepsy and 59.8% (95% UI, 24.9–89.7) of the losses due to porcine cysticercosis. The cost per NCC-associated epilepsy case was 72 USD (95% UI, 25–168), representing 30.8% of the GDP per capita in 2020. The probable incident cases and deaths for NCC-associated epilepsy were 9065 (95% UI, 2370–16,716) and 61 (95% UI, 16–114), respectively. More than 2 zDALYs (95% UI, 1.1–3.4) per thousand person-years was estimated, of which an average of 1.3 DALYs [0;0] (95% UI, 0.3–2.6) was due to NCC- associated epilepsy and 0.8 animal loss equivalents (ALEs) (95% UI, 0.3–1.5) due to porcine&nbsp;cysticercosis. Conclusions. This study provides evidence of a significant burden of T. solium cysticercosis for Burundi’s population. We urge policy makers to use these evidence-based results and put T. solium cysticercosis on the public health agenda of the country. This study recommends urgent action to find solutions for integrated control strategies for T. solium cysticercosis in&nbsp;Burundi.</p

    Association between severe acute malnutrition during childhood and blood pressure during adulthood in the eastern Democratic Republic of the Congo: the Lwiro cohort study

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    Abstract Introduction Little is known about the long-term outcomes of Severe Acute Malnutrition (SAM) during childhood. As such, this study aims to explore the association between childhood SAM and blood pressure (BP) in adulthood in a context without nutrition transition. Methodology We identified 524 adults (Median age: 22 years) who were treated for SAM during childhood in Eastern DRC between 1988 and 2007. They were compared with 407 age-and-sex matched subjects with no history of SAM in the community. The variables examined for this study were the systolic (SBP), diastolic (DBP), mean (MBP) blood pressure (BP) and pulse pressure (PP), as well as high blood pressure (HBP) defined as BP ≥ 140/90 mmHg and/or use of BP-lowering drug(s) in adulthood. For comparison, linear and logistic regression models were used for analysing continuous and dichotomous variables, respectively. Results Of the 524 exposed located, 145 were selected according to age. A total of 97 unexposed were recruited. Compared to unexposed, exposed had slightly higher SBP and PP after adjusting for occupation, body mass index (BMI) and food consumption [SBP = 1.4 mmHg (− 2.2, 4.8) and PP = 2.6 mmHg (− 0.3, 6.0)]. However, their DBP was lower than that of the unexposed [− 1.6 mmHg (− 4.6, 1.5)]. MBP and creatinine levels were similar between the two groups. The prevalence of HBP adjusted for age was higher among exposed than unexposed (9.7% vs 5.3%). In addition, the odds of having HBP was higher among exposed than unexposed, however the observed difference was not statistically significant [Odds Ratio (OR) 1.9 (0.7, 5.6)]. Finally, using multiple regression analysis, although the effect was not significant, SAM was a major contributor to HBP [adjusted OR 3.1 (0.9,10.9), p = 0.064], while only male gender and higher BMI (overweight/obesity) emerged as independent predictors of HBP among this young study population. Conclusions This study suggests that an episode of SAM in childhood has a weak impact on BP variability in young Congolese adults (from DRC) living in an environment without nutrition transition. However, people who experienced a period of SAM tended to have a higher prevalence of HBP and a much higher risk of developing HBP than unexposed. Additional multicentre studies involving a larger cohort would provide greater understanding of the impact of SAM on the overall risk of BP disorders during adulthood. </jats:sec

    Association between severe acute malnutrition in childhood and hematological disorders in adulthood: the Lwiro follow-up study in the Eastern Democratic Republic of the Congo

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    Abstract Background: Despite growing evidence on the short-term deleterious effects of severe acute malnutrition (SAM) in childhood on hematopoiesis, little is known about the long-term hematological effects of SAM in low-income countries (LICs). Our study explored the association between childhood SAM and hematological disorders in young adults 11 to 30 years after post-SAM nutritional rehabilitation. Methods: This follow up study investigated 97 adults (mean age 32 years) treated for SAM during childhood in eastern Democratic Republic of the Congo (DRC) between 1988 and 2007. Participants were compared to 97 aged- and sex-matched adult controls living in the same community with no history of SAM. Outcomes of interest were hematological characteristics and disorders in adulthood, assessed by various biological markers. Logistic and linear regression models were used to estimate the association between SAM in childhood and risk of hematological abnormalities. Results: Compared to the unexposed, the exposed had higher mean white blood cells (/µl) [+840 (179 to 1501), p=0.013], neutrophils [+504 (83 to 925), p=0.019] and platelets (*103) [11.9 (8.1 to 17.9), p=0.038] even after adjustment for food consumption in adulthood. No difference was observed in red blood cells (RBC), hemoglobin and erythrocytes parameters. With regard to the risk of hematological disorders, in contrast to the unexposed, exposed subjects had a risk of hyperleukocytosis approximately three times higher [adjusted OR (95% CI): 2.98 (1.01 to 8.79), p=0.048]. No difference was observed in terms of anemia, leukopenia, increased platelets and thrombocytopenia between the 2 groups. Conclusion: Adults with a history of SAM in childhood have hematological characteristics that could predispose to chronic low-grade inflammatory or infectious diseases that persists after nutritional rehabilitation in an environment with no nutritional transition. Larger cohort studies with bone marrow analyses could provide further understanding of the impact of SAM on the overall hematological profile in adult life</jats:p
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