Study on the parasitic and microbial contamination of vegetables, and the effect of washing procedures on their elimination in Ilam city

Abstract

The risk of disease spread through water, fruits and vegetables contaminated through unclean waters varies from region to another. Springs and underground water resources are essentially free of germs or they have tolerable levels of germs; unless they are infected by surface water or human excreta. Scientific reports have shown that outbreaks of food-borne illnesses especially foods such as fresh fruit and vegetables are rising. The aim of the study is to evaluate the effect of washing procedures in eliminating of microbial and parasitic contamination of vegetables consumed in Ilam city. Multiple samples of vegetables were collected from five regions of the city (North- South- West- East- Center) about 1 kg from each shop and transferred to the laboratory. Then we put apiece in a dish containing five liters water; vegetable was washed into it and a sample was collected. Then we added to dish, 20 drops of dish soap and mixed it for a few minutes so that all of vegetable dipped in the foam. After a few minutes, the vegetable were washed with pure water. Another sample was collected from sewage of this water. For detection of microbes, we used two methods: formalin eater and direct microscopic observation. 86 samples were collected from five regions of city. 40.6% of them had parasitic contamination in scantling water of washing with pure water, and 43% had parasitic contamination in scantling water of washing with dish soap. 70.9% of them had parasitic and bacterial contamination in both wastewaters. There was no significant difference between washing with water and washing with dish soap for parasitic or bacterial contamination. Methods of washing in some types of vegetable may reduce effectively parasitic infection; but we found that washing with dish soap didn’t have any significant effect on reduction of microbial contamination.