Parasitological contamination in lettuces (Lactuca sativa var. crispa), from traditional and hydroponic cultivations, commercialized in free markets of Rio de Janeiro (RJ)

Abstract

One hundred samples of lettuce were collected from two free markets in the North Zone of Rio de Janeiro, Brazil, being 50 samples of traditional cultivation and 50 of hydroponic one. These samples were analyzed by means of parasitological sedimentation and flotation techniques. Twelve (12 %) samples were positive for evolutionary forms of helminths or protozoa of medical and veterinary importance, as cyst of amoebids, oocyst of coccidian and eggs of helminths of Ancylostomatoidea superfamily, and similar frequency of positive samples was found among the lettuce samples of traditional and hydroponic cultivations. Contamination with free living organisms was detected, but without association with the evolving forms of parasites in 85 % of samples. The presence of contaminants in the majority of samples, with detection of evolutive forms of human or other animals intestinal parasites, indicate that these vegetables may represent a potential source of contamination for humans, and they are unsuitable for consumption before being properly disinfected.