Water Resource Engineering

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Browsing Water Resource Engineering by Author "Adey Feleke (PhD)"

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    Biomarkers of Toxins in Improved Drinking Water and Diarrhea Patients of South Wollo Communities, Northern Ethiopia
    (Addis Ababa University, 2022-04) Shibabaw Tadesse; Sirak Robele (PhD.); Adey Feleke (PhD); Jana Jass (Prof.)
    The world's most vulnerable communities frequently drink contaminated water, which is linked to a variety of public health issues. Escherichia coli toxins are the most common types of contaminants found in association with disease in E. coli bacteria. They are found in nearly all pathogenic E. coli bacteria either released from the bacteria or E. coli cell or both transmitted via the feco-oral route. The objective was to evaluate the safety of improved water supplies using toxins as a biomarker and correlate with the toxins found in patient stools, and identify gaps between water quality and the global classification of improved water supplies in the South Wollo zone, Ethiopia. This dissertation reports the results of a laboratory-based cross-sectional study conducted in South Wollo, Ethiopia, from January 2019 to June 2020. Two hundred forty-eight samples of household water and patient stool were collected (in a 1:1 match) and toxins were tested using polymerase chain reaction (PCR). The targeted toxins used were (enteroaggregative E. coli heat-stable enterotoxin 1 (EAST1), heat-stable (Sta); shiga-like toxin 1 (Stx1), shiga-like toxin 2 (Stx2), and heat-liable (LT)), which cause diarrhea when people drink contaminated water. A survey questionnaire was used to gather information on the types of water sources, as well as the knowledge and practices of the respondents about household water treatment methods. To analyze the data and examine the relationship between the variables, descriptive statistics, Chi-square (χ2), Fisher’s exact test, logistic regression, and Pearson’s bivariate correlation coefficients were used. In general, 24% of households had positive results from both water and stool samples, 63% [Confidence Interval (CI): 55- 67%] had positive results from water samples only, and 46% [CI: 37- 49%] had positive results from only stool frequently, with 33% in the water and 38% in the stool. Frequently founded contaminants in household water brought from improved water sources were the toxins ESAT1, Stx1, and LT, with Sta the least founded (2%). There were fewer (13%) toxins detected in shallow groundwater sources than in piped water, a statistically significant difference (P=0.031). There was a lower proportion of toxins detected in those who did not know about and used cloth filters than in those who did, and the negative relationship is statistically significant (P=0.017). Approximately one-third of the improved water services sampled, which are considered ‘functional’ by international standards, do not provide potable water due to fecal and toxin contaminants. There was a significant positive correlation (r = 0.412) between toxins in the stool and toxins in the water (P < 0.05). The findings indicate that toxin biomarkers can be used to monitor water safety. Water quality parameters are not currently considered in the classification of basic water services. This suggests that international efforts to address SDG 6 should incorporate water quality and its indicators as a key parameter to better track international progress towards ‘clean water and sanitation’ efforts. More research is needed to determine the sources of pathogenic microbial markers that cause water-related diseases, such as diarrhea, as well as focus areas for water contamination prevention.samples for toxins. Out of the five toxins examined, EAST1 was the one that was found the most