الفهرس 
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Abstract
Raw vegetables are essential part of the healthy human diet owing to their nutritional value. They are great source of vitamins, dietary fibers and minerals , their regular consumption is associated with a reduced risk of dangerous diseases, new trends are directed toward eating raw : as salad. It may further increase the possibility of foodborne infections which could be contaminated with parasitic pathogens.
The consumption of contaminated raw vegetables, represent a public health concern for human being, mainly in developing countries.
In the present study a survey undertaken between 2017 and 2018 to assess the extent of parasitic contamination of various eaten raw vegetables available commercially in Assiut city.
240 vegetable samples were examined (40 sample of each of watercress, radish, parsley, coriander, green onions and lettuce)
Sampling was conducted monthly of each type in sufficient quantity 200gm, the samples were divided into four parts in equal units (50 gm), Each sample was treated with four different washing methods(distilled water, distilled water with vinegar, distilled water for one hour and distilled water for 24 hours).
Samples were examined by direct wet method, lactofenol cotton blue, Ziehl Nelseen and Acridine orange stains.
The results obtained in the present study showed that 202 out of 240 of vegetable samples were positive for parasitic contamination (84.1% ) (37 in watercress, 37 in radish, 38 in parsley, 29 in coriander, 34 in green onions, and 27 in lettuce). The highest number of parasitic contamination was observed in parsley (274), followed by radish (255) watercress (222), green onions (258) and coriander (117) ,the lowest was observed in lettuce (71).
Various parasites were detected in the examined vegetables including helminthes parasites (Cestodae eggs, Trematodes, Nematode larvae), protozoan parasites (Cryptosporidium, Cyclospora, Giardia lamblia, Entamoeba spp,Eimeria,Isospora) and different Arthropods.
The most encountered contaminating parasite was Cryptosporidium spp. oocysts with (69.4%) of all examined vegetable samples regardless of the wash type, followed by Arthropods (9.4%) and Eimeria sp. (9.0%).
Giardia and Cyclospora spp. were the least commonly encountered parasites (1.4%) in all examined vegetables.
The contamination rate showed significant variation among vegetable types. Parsley was found the most contaminated vegetable among all examined, followed by green onion, radish, watercress and coriander, and the least contamination rate was observed in lettuce.
Regarding the wash methods, the maximum finding parasites were observed on wash 2 (vinegar &water) which was significantly higher than other wash types (p≤ 0.0001).
In relation to the viability and methods of wash, it was found that,
viability percent showed the lowest results in all vegetables examined by wash 2 compared with other wash types (p≤0.0034).
Wash 4 came in the second rank in parasite detecting mean count, while the parasite viability for it showed the highest results.
Wash 1 was the least effective one in raw vegetables parasites recovery (mean count).
The relatively high prevalence of these parasites in raw consumed vegetables establishes a baseline for further studies and suggests a need for additional research with respect to the possible sources of contamination of these foods, the determination of parasite viability and virulence, to reduce foodborne transmission to humans.