Microbial contamination of biodigester effluents in the La Dadekotopon district of Accra, Ghana

Challenges in wastewater treatment have prompted the adoption of cost-effective and environmentally cleaner biodigesters as alternatives to septic tanks. However, their effectiveness in the field is uncertain. This study investigated the effluent quality from bio-digesters and assessed enteric bacterial contamination in the La community. We evaluated the quality of effluents from bio-digesters in six suburbs by measuring Total coliform (T. C) and faecal coliform counts. We also tested food pack samples and hand rinse/hand washing water from vendors for T.C., Escherichia coli contamination, moulds, and yeast. Additionally, we analysed reported enteritis cases from 2016 to 2019 to assess prevalence. Biodigesters discharged effluent with E. coli concentrations from 2.6 × 10⁶ to 6.51 × 10⁶ cfu/ml, and T. C levels ranged from 50 × 10 5 to 930 × 10 5 cfu/ml. Leaf food packs had yeast counts from 520 to 2808 cfu/ml. For hand rinse/hand washing water, T.C. levels varied from 5.0 × 10⁴ to 1395 × 10⁴ cfu/mL, and E. coli levels ranged from 1.0 × 10⁴ to 651 × 10⁴ cfu/ml. The prevalence of typhoid fever increased with age, while diarrhoeal diseases decreased. Biodigester effluent exceeded E.P.A Ghana's permissible levels for total and faecal coliforms. High yeast levels were found in food leaf packs, and hand rinse/hand washing water showed elevated coliform counts, which pose infection risks for consumers, especially since vendors sometimes serve food with bare hands. Regular community engagement in water, sanitation, and hygiene (WASH) practices is essential to achieve SDGs 6 and 3.