Abstract

This study assessed Salmonella species contamination in irrigation water and market gardening products in urban agricultural sites across Dakar, Senegal. Three key locations, Pikine, Patte d’Oie, and Lendeng, were evaluated, representing different water sources: wastewater, tap water, and traditional wells (Ceanes). Samples of irrigation water and lettuce were collected and analyzed for microbial pathogens. Results demonstrated significant variations in contamination levels. Sites using wastewater (Pikine and Patte d’Oie) exhibited high Salmonella spp. prevalence in water (70 and 90%, respectively) and vegetables (80 and 20%). In contrast, lendeng, which relied on tap water, showed no contamination. Market-sourced lettuce samples also tested positive (28.57%), likely due to cross-contamination from high-risk areas. Statistical analysis confirmed a strong correlation (p < 0.05) between irrigation water source and contamination rates, with wastewater posing the highest risk. These findings underscore the public health risks of untreated wastewater use in urban agriculture and highlight the urgent need for improved water quality management to ensure food safety. The study aligns with regional research in West Africa, calling for policy interventions to mitigate microbial hazards in irrigation practices.

Key words: Waste water, contamination, irrigation water, Salmonella, urban agriculture, food safety, Dakar.