Origin of fluoride and arsenic in the main ethiopian rift waters

In the Main Ethiopian Rift (MER) area, rural populations often use water that exceeds the World Health Organization thresholds for fluoride (F–) and arsenic (As), two elements that are hazardous for human health. In this study, twenty-nine water samples were collected from lakes and hot and cold springs in southern MER to investigate source(s) and health-risk of the F– and As contamination. According to major ion and trace element analyses, only cold spring water is safe for consumption, whereas hot spring water is the most contaminated. Leaching tests performed with the MER rhyolitic volcanic rocks and their weathered products (fluvio-lacustrine sediments) demonstrate that the main cause of the F– and As release is geogenic, i.e., not related to anthropogenic activities. The weathering of volcanic glass and minerals (apatites, clays, hydro-oxides) by CO2-bearing alkaline water induces the mobilisation of F– and As from solid to liquid phase. This process is particularly fast, when fluvio-lacustrine sediments are involved, and can be further enhanced by hot groundwater leaching. This study, investigating the distribution, sources, and mechanisms of F– and As release in MER water, could be of interest also for other sectors of the East African Rift and other similar volcano-tectonic settings

Water Quality Threats, Perceptions of Climate Change and Behavioral Responses among Farmers in the Ethiopian Rift Valley

This work aims to assess water quality for irrigated agriculture, alongside perceptions and adaptations of farmers to climate change in the Main Ethiopian Rift (MER). Climate change is expected to cause a rise in temperature and variability in rainfall in the region, reducing surface water availability and raising dependence on groundwater. The study data come from surveys with 147 farmers living in the Ziway–Shala basin and water quality assessments of 162 samples from groundwater wells and surface water. Most groundwater samples were found to be unsuitable for long term agricultural use due to their high salinity and sodium adsorption ratio, which has implications for soil permeability, as well as elevated bicarbonate, boron and residual sodium carbonate concentrations. The survey data indicate that water sufficiency is a major concern for farmers that leads to frequent crop failures, especially due to erratic and insufficient rainfall. An important adaptation mechanism for farmers is the use of improved crop varieties, but major barriers to adaptation include a lack of access to irrigation water, credit or savings, appropriate seeds, and knowledge or information on weather and climate conditions. Local (development) agents are identified as vital to enhancing farmers’ knowledge of risks and solutions, and extension programs must therefore continue to promote resilience and adaptation in the area. Unfortunately, much of the MER groundwater that could be used to cope with declining viability of rainfed agriculture and surface water availability, is poor in quality. The use of saline groundwater could jeopardize the agricultural sector, and most notably commercial horticulture and floriculture activities. This study highlights the complex nexus of water quality and sufficiency challenges facing the agriculture sector in the region, and should help decision-makers to design feasible strategies for enhancing adaptation and food security

Dietary exposures to metals in relation to chronic kidney disease of unknown cause (CKDu) in Sri Lanka

Exposure to metals has been hypothesized as possible cause of chronic kidney disease of unknown cause (CKDu) in Sri Lanka; however, evidence is inconclusive. We measured the concentrations of nephrotoxic metals (As, Pb, and Cd), as well as Se in rice (a staple grain in Sri Lanka) and other grains consumed in CKDu endemic and non-endemic regions using Inductively Coupled Mass Spectrometry (ICP-MS). Our results showed comparable mean concentrations (in µg/kg) of 24.5±18, 7.3±6.4, and 14.2±15 for As, Pb, and Cd, respectively, in rice from endemic regions and 17.7±4.7, 12.7±6.8, and 17.8±16 in rice from non-endemic regions. Selenium concentrations (in mg/kg) were 0.05±0.02 in rice cultivated in both endemic and non-endemic regions. Arsenic and Cd concentrations were significantly higher in rice compared to other grains, which themselves had higher Se than rice. All samples were below the Codex standards established for Cd (400 µg/kg for rice; 100 µg/kg for cereal grains), Pb (200 µg/kg) and inorganic As (200 µg/kg) for white rice. Our findings show that dietary exposure to low levels of As, Pb, Cd, and inadequate Se in staple grains cannot be clearly linked to CKDu, suggesting that the disease could be multifactorial. Additional research is needed to determine the contribution of other risk factors such as lifestyle habits and heat stress to plan preventive strategies for reducing CKDu health cases in Sri Lanka

Origin of fluoride and arsenic in the Main Ethiopian Rift waters

In the Main Ethiopian Rift (MER) area, rural populations often use water that exceeds the World Health Organization thresholds for fluoride (F–) and arsenic (As), two elements that are hazardous for human health. In this study, twenty-nine water samples were collected from lakes and hot and cold springs in southern MER to investigate source(s) and health-risk of the F– and As contamination. According to major ion and trace element analyses, only cold spring water is safe for consumption, whereas hot spring water is the most contaminated. Leaching tests performed with the MER rhyolitic volcanic rocks and their weathered products (fluvio-lacustrine sediments) demonstrate that the main cause of the F– and As release is geogenic, i.e., not related to anthropogenic activities. The weathering of volcanic glass and minerals (apatites, clays, hydro-oxides) by CO2-bearing alkaline water induces the mobilisation of F– and As from solid to liquid phase. This process is particularly fast, when fluvio-lacustrine sediments are involved, and can be further enhanced by hot groundwater leaching. This study, investigating the distribution, sources, and mechanisms of F– and As release in MER water, could be of interest also for other sectors of the East African Rift and other similar volcano-tectonic settings

Sustainable Use of Extracts of Some Plants Growing in Ethiopia for the Formulation of Herbal Shampoo and Its Antimicrobial Evaluation

Shampoo prepares surfactants to remove dirt, surface grease, and skin debris from hair, shaft, and scalp without harming the user. This study aimed to formulate herbal shampoo using Ethiopian plant extracts and evaluate their quality parameters. Herbal shampoos were formulated using seed oil extracts of Lepidium sativum L. and Ricinus communis L., and essential oil extracts of Lippia adeonsis Hochst ex. Walp koseret, along with other ingredients. The formulated herbal shampoos were evaluated for their organoleptic and physicochemical properties such as pH, surface tension, viscosity, dirt dispersion, antimicrobial activities, and stability. When the investigation data were assessed, the formulations were pleasant and attractive, produced sufficient foam, and showed suitable cleansing activities. The pH values were in a range 5.90 ± 0.22–7.45 ± 0.19, and lower surface tension (23.39 ± 0.20–31.89 ± 1.04 dyne/cm) together with acceptable viscosity with good shearing properties were obtained. The formulated products exhibited good antimicrobial activities against Escherichia coli, Staphylococcus aureus, and Aspergillus niger. When the surface morphologies of hair samples were examined using a scanning electron microscope (SEM), a clean and smooth surface was observed for treated samples, comparable to that of the marketed shampoo. This result indicated that the formulated herbal shampoo is good, having acceptable properties at par with commercially available shampoos. However, further investigation, research, and development are required to improve its quality and safety