Parasitic Contamination of Lettuce, Tomato and Cucumber from Vegetable Farms in Mali

Abstract

This study aimed to determining the parasitic contaminants of lettuce, tomato and cucumber from some vegetable production sites in Mali, in order to assess the health risk related to their consumption. Fresh vegetables are an essential component of a balanced diet. When eaten uncooked, they have the potential to transmit intestinal parasites. The frequency and variability of parasite eggs were assessed on thirty-two lettuce, tomato and cucumber samples from irrigated vegetable farms in Bamako, Kati, Baguineda, Samanko, Sikasso, and Niono.  Counting parasite eggs and cysts in 100 g of vegetable was used to determine the parasite load. The overall prevalence of parasite contamination of vegetables was 20.83 percent, with lettuce accounting for 41.66 percent and tomato accounting for 16.66 percent. Cucumber had no parasite eggs on it. Parasites found on the vegetables were Entamoeba coli and Trichomonas intestinalis (24.19% each), Ascaris lumbricoides (13.25%), Giardia intestinalis (12.9%), Balantidium coli (11.29%), Entamoeba histolitica (7.26%), Fasciola hepatica (3.23%), Trichinella spiralis (1.61%), Ancylostoma duodenale and Schistosoma intercalatum (1.04% each). In Bamako and Niono, parasites on lettuce were found in 83.33 percent of cases, 50.00 percent in Kati, 16.66 percent in Baguineda and Samanko, and 0.00 percent in Sikasso. Consumption of parasite-infested vegetables poses a health risk to customers. Some agronomic practices undertaken by vegetables farmers in Mali could be a source of parasitic contaminations and potentially put the health of farmers and consumers. Undecomposed manure, open defecation in farms, run-off water from drains, contaminated soil and irrigation water and overhead irrigation are likely sources of lettuce, tomato and cucumber contamination in many vegetables’ farms. There was the need for scientific quantitative data to trace pathway by which parasites get to irrigated vegetables, to determine key points where health risk reduction interventions could be applied.