Study on the occurrence of intestinal parasites on vegetables commercially traded in the metropolitan area of S.Paulo, SP, Brazil: I - Search for helminths

Carlos Augusto Fernandes de Oliveira Pedro Manuel Leal Germano About the authors

Vegetables in natura, commercially traded in the metropolitan area of S. Paulo, were analysed by the appropriate methodology with a view to discovering an identifying the paths of transmission of enteroparasites of medical interest. The vegetables under study consisted of 50 samples of each variety listed below: lettuce (Lactuca sativa) -oily leaves and crisphead varieties, endive (Chicorium sp) and water-cress (Nasturtium Officinale). Results showed high rates of contamination in all the vegetable varieties analysed. However, the water-cress was that which presented the highest frequencies of enteroparasites. The endive presented middle values ranking, in general, between the lettuces and the water-cress. Though high, the average number of helminth eggs and larvae obtained per 100 gr. of sample did not present statistically significant differences as between the four vegetable varietities studied. A great variety of helminths and protozoans such as occur frequently in the resident population of the metropolitan area of S. Paulo, were observed in the samples. However, the most frequent were: hookworms and Ascaris sp. Eggs of Toxocara sp, Fasciola sp and Trichostrongylidae were also recovered from the samples thus corroborating the occurrence of vegetables contamination with faeces of domestic animals. In view of the results obtained, the importance of these kinds of food in the transmission of enteroparasites is stressed, as well as the need for actions which improve the sanitary conditions of these products.

Food contamination; Helminths; Vegetables

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