Organic vegetables safety: sanitary and nutritional aspects

The search for organic foods is expressive worldwide due to the population awareness about the health risks resulting from the presence of chemical residues in food. Several studies suggest that some practices of organic farming, such as the use of animal manure and rules prohibiting the use of conventional pesticides, can increase the microbiological and parasitic risks. Hence, these foods would not be suitable for human consumption. In this context, the present research aimed at determining the sanitary quality of organic vegetables through the evaluation of microbiological contamination by total and fecal and coliforms, Salmonella sp., and parasitological contamination. Moreover, samples of organic lettuce, carrots, and tomatoes from the Metropolitan Region of Curitiba, Parana, were submitted to physicochemical evaluation to assess their nutritional quality. Thermotolerant coliforms, or fecal coliforms, were detected in 40% of the lettuce and in 25% of the carrot samples. It was observed that 25% of the carrot and 20% of lettuce samples presented Salmonella sp., whereas the tomato samples did not present thermotolerant coliforms or Salmonella sp. The major parasites identified in the lettuce samples were acarus, Entamoeba sp., eggs of Ancylostoma sp., and insects. Entamoeba sp., eggs of Ancylostoma sp. and Toxocara sp. were identified in the organic carrot samples, while the tomato samples did not present any parasitological contamination. The data suggest that the organic lettuce and carrot samples might have been contaminated somehow by the soil, water, domestic animals, or non-suitable fertilizers.