Abegaz & Midekssa 2021 — Rural drinking water quality in Guto Gida, Ethiopia
This cross-sectional study assessed the bacteriological and physicochemical quality of 32 drinking water samples collected from four source types (protected dug well, open dug well, protected spring, open spring) at 8 locations in the Guto Gida woreda of Oromia, Ethiopia. The study found widespread microbial contamination and chemical non-compliance, with lead concentrations exceeding WHO permissible levels at two sites (J2 and K1) in both spring and well categories. Iron and manganese also exceeded permissible limits across multiple sources.
Key numbers
Lead concentrations (mg/L, triplicates averaged per site):
- Unprotected wells: range 0.00–0.15 mg/L; overall mean 0.005 ± 0.005 mg/L across 8 sites; K1 site: 0.15 ± 0.1 mg/L (above WHO limit of 0.05 mg/L)
- Unprotected springs: range 0.01–0.15 mg/L; J2: 0.15 ± 0.09 mg/L, K1: 0.07 ± 0.04 mg/L (both above WHO limit)
- Protected springs: range 0.00–0.18 mg/L; K1: 0.18 ± 0.20 mg/L, J2: 0.11 ± 0.10 mg/L (both above WHO limit)
- Protected wells: range 0.01–0.15 mg/L; J2: 0.15 ± 0.09 mg/L, K1: 0.07 ± 0.04 mg/L (above WHO limit)
Iron (mg/L): overall means 0.32 (unprotected wells), 0.26 (unprotected springs), 0.51 (protected wells), 0.55 (protected springs); multiple sites exceeded WHO limit of 0.3 mg/L.
Manganese (mg/L): overall mean 0.51 ± 0.24 mg/L in protected springs, significantly higher than other source types (0.20–0.21 mg/L); multiple sites exceeded WHO limit of 0.1 mg/L.
Zinc (mg/L): highest value 3.9 ± 2.02 mg/L in protected spring J2; means 1.40–2.21 mg/L across source types.
Fluoride: three unprotected well sites and three unprotected spring sites exceeded WHO limit of 1.5 mg/L; highest was 3.81 mg/L at unprotected spring D1.
Microbiology: 90.6% of samples positive for total coliform and 87.5% for faecal coliform; 87.5% of sources fell into the WHO “medium risk” category (TC counts 11–100 CFU/100 mL).
Analytical method: Hach Model DR/2400 Portable Spectrophotometer for physicochemical parameters following APHA and WHO standard protocols; data collected 2016.
Methods (brief)
Cross-sectional study, January–June 2016. Water samples collected in triplicate from 32 sampling points across 8 locations. Physicochemical parameters (iron, manganese, lead, zinc, fluoride, nitrate, sulphate, phosphate, pH, TDS, EC, turbidity, color, temperature) measured by Hach DR/2400 Portable Spectrophotometer following APHA and WHO protocols. Bacteriological analysis by membrane filtration with Lauryl Sulphate Broth, incubated at 37°C (total coliform) and 44°C (faecal coliform). SPSS v20 for statistics; one-way ANOVA with DMRT post-hoc; Pearson’s correlation. No LOD/LOQ values stated for the heavy metal measurements. All values reported as wet weight (mg/L in water).
Implications
Certification: Primarily drinking-water relevance; not a food-matrix source for HMT&C product thresholds. Documents naturally elevated lead in rural Ethiopian well and spring water from geological and agricultural sources.
Courses: Useful case study for water-source contamination in sub-Saharan Africa and the challenge of rural water quality compliance with WHO standards.
App: Not applicable; drinking water rather than food ingredient.