Aneugenicity and clastogenicity in freshwater fish Oreochromis niloticus exposed to incipient safe concentration of tannery effluent.

Conventional effluent bioassays mostly rely on overt responses or endpoints such as apical and Darwinian fitness. Beyond the empirical observation, laboratory toxicity testing needs to rely on effective detection of prognostic biomarkers such as genotoxicity. Indeed, characterization of tannery effluent requires slotting in of genotoxic responses in whole effluent toxicity testing procedures. Hence, the prime objective of the present experimental investigation is to apply the technique of biological assay as a tool of toxicity testing to evaluate the induction of micronuclei (MN) in peripheral erythrocytes, and exfoliated cells of gill and kidney of O.niloticus exposed to Maximum tolerable concentrations (MTCs) of composite Modjo tannery effluent (CMTE) and to compare the sensitivity of each cells origin to the induction of MN. After 72h of exposure, cellular aberrations were detected using MN and nuclear abnormality (NA) tests. The induction of MN was significantly higher in exposed groups (P<0.05) when compared to the control group; moreover the tissue specific MN response was in the order, gill cells>peripheral erythrocyte>kidney. Total NA was found to increase significantly (P<0.05), when compared to the non-exposed group. NA was also further ramified as blebbed (BL), bi-nucleated (BN), lobbed (LB) and notched (NT) abnormalities. The result of each endpoint measured has demonstrated that at a concentration of total chromium (0.1, 0.73 and 1.27mg/L), a perceptible amount cellular aberration was measured, further implicating somber treat of genotoxicity to fishes, if exposed to water contaminated with tannery effluent. This further highlight that conventional effluent monitoring alone cannot reveal the effects expressed at cellular and genetic levels further demanding the incorporation of effluent bioassays in risk assessment and risk management/abatement programs.

Adherence to infection prevention and control measures and risk of exposure among health-care workers: A cross-sectional study from the early period of COVID-19 pandemic in Addis Ababa, Ethiopia.

Background and Aim: Healthcare workers (HCWs) are considered a high-risk group for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) exposure, ascribed to the amount of time they spend in health-care facilities (HCFs). This study aimed to assess HCWs' compliance with Infection Prevention and Control (IPC) procedures and the risk of exposure during the early period of the pandemic in Addis Ababa, Ethiopia. Methods: A descriptive cross-sectional survey was conducted from June to September 2020. With a response rate of 79.2%, a standardized questionnaire was administered among 247 HCWs, working in eight HCFs. Descriptive and multivariate regression analysis was carried out in STATA version 16. Results: About 22.5% (55) of the HCWs had proper adherence to IPC procedures. Of the total participants, 28.2% (69) had proper use of Personal Protective Equipment (PPE), 40% (98) had proper hand hygiene practices, and 33.1% (81) had frequently cleaned their working environment. HCWs who received training on IPC protocols were four times more likely to follow IPC standards than those with no training (adjusted odds ratio [AOR] = 3.93; 95% confidence interval [CI]: 1.46, 10.58). Besides, HCWs working in treatment centers were four times more likely to follow IPC standards than those working in conventional hospitals (AOR = 3.61; 95% CI:1.63, 8.02). Nurses were four times more likely to have adherence to IPC measures than cleaners and runners (AOR = 4.37; 95% CI: 1.38-13.88). Conclusion: The nature and magnitude of the pandemic did not introduce the required degree of adherence to IPC procedures, per se does not match the level of diligence needed to halt SARS-CoV-2 transmission. Our finding suggested that providing periodic training of HCWs with particular emphasis on nonclinical staff is commendable. Furthermore, it is necessary to maintain resilent IPC in HCF through continous follow up and safety drills, to assess the readiness of HFCs' adherance to IPC measures under normal circumstances, which could improve prepardeness for an effective response during epidemics.

Metals exposures of residents living near the Akaki River in Addis Ababa, Ethiopia: a cross-sectional study.

BACKGROUND: The Akaki River in Ethiopia has been found to contain elevated levels of several metals. Our objectives were to characterize metals exposures of residents living near the Akaki River and to assess metal levels in their drinking water. METHODS: In 2011, we conducted a cross-sectional study of 101 households in Akaki-Kality subcity (near the Akaki River) and 50 households in Yeka subcity (distant to the Akaki River). One willing adult in each household provided urine, blood, and drinking water sample. RESULTS: Urinary molybdenum (p < 0.001), tungsten (p < 0.001), lead (p < 0.001), uranium (p < 0.001), and mercury (p = 0.049) were higher in Akaki-Kality participants compared to Yeka participants. Participants in both subcities had low urinary iodine; 45% met the World Health Organization (WHO) classification for being at risk of moderate iodine deficiency. In Yeka, 47% of households exceeded the WHO aesthetic-based reference value for manganese; in Akaki-Kality, only 2% of households exceeded this value (p < 0.001). There was no correlation between metals levels in water samples and clinical specimens. CONCLUSIONS: Most of the exposures found during this investigation seem unlikely to cause acute health effects based on known toxic thresholds. However, toxicity data for many of these metals are very limited.