Physicochemical and parasitological quality of vegetables irrigation water in Ouagadougou city, Burkina-Faso

The quality of irrigation water from different sources used by urban vegetable producers, the watered soils and vegetables in Ouagadougou was investigated. From December 2012 to December 2013, samples of water (97), lettuces heads (20), manure (10) and soil (9) were collected and analyzed for their parasitological quality using modified Bailenger methods. The result shows that parasites concentration in samples (1 to 11 egg/L in water, 0.45 egg/g on lettuce and 0.48 egg/g in soil) are above the threshold levels set by WHO/FAO for unrestricted irrigation. Different protozoa and helminthes belonging to 9 species were identified in the samples analyzed. These include Ankylostoma duodenalis, Hymenolepis nana, Ascaris lombricoïdes, Taenias ssp., Strongyloides stercoralis, Entamoeba histolytica, Giardia lamblia and Entamoeba coli. Despite variation in isolated parasites, eggs of A. lumbricoïdes and A. duodenalis were common in all water, soil and vegetables. Furthermore 14.87% of collected eggs have proven to be viable with predominance of helminthes eggs. As a result, farmers appear to be the most exposed group to helminthiasis.