Parasitic Contamination of Raw Vegetables Consumed inHamadan, West of Iran During 2017-2018

Healthy diets including fruits and vegetables reduce the risk of chronic diseases. This study was aimed at detecting parasitic contamination caused by consuming raw vegetables sold in Hamadan, west of Iran. A total of 380 vegetable samples consisting of parsley, coriander, basil, savory, mint, cress, tarragon, leek, radish and spring onion were evaluated microscopically after conducting sedimentation and flotation from April 2017 to March 2018. Parasites were detected in 95 out of 380 of vegetable samples (25%). The organisms identified included Entamoeba coli (8.15%), Ascaris lumbricoides (7.1%), Chilomastix mesnili (5%), and Giardia lamblia (1.5%), Blastocystis hominis (0.78%), Toxocara canis (0.26%) and Hymenolepis nana (0.26%). High level of contamination was obtained for parsley (5.52%) while radish was the least contaminated (0.78%). Vegetable contamination was higher in spring and summer (20.6%) (P<0.0001). Samples collected from vegetable fields irrigated by well water supply showed low parasitic contamination (28.5%) compared to those from farms irrigated by surface or sewage water (91%) (P<0.0001). The results emphasize the potential role of raw vegetables consumption in transmission of pathogenic organisms. Besides, it was highlighted that irrigation of vegetables by surface water could be the source of vegetable contamination with human intestinal parasites.