Salmonella spp at critical points in organic vegetables production chain in the state of São Paulo: contribution for risk assessment

Abstract

The consumption of vegetables is encouraged by health authorities around the world due to their health benefits. However, sanitary surveillance data in several countries point out an increasing association of vegetable consumption with outbreaks of foodborne diseases caused by pathogenic microorganisms. Organic practices in agriculture, such as use of animal manure and inadequate composting, may increase the possibility of contamination by enteric microorganisms such as Salmonella spp, increasing health risks for the consumer. This research project aims at a better understand the reality of organic agriculture in the State of São Paulo and generate data that may contribute to risk assessment associated with consumption of organic vegetables, focusing on Salmonella spp. The study will be carried out in ten fields of organic vegetables production located in the state of São Paulo, researching Salmonella spp. and indicators of fecal contamination (Enterobacteriaceae) in vegetables, fertilizers (manure) and irrigation water. Vegetables will be sampled directly from the soil and also at the moment of release for distribution and commercialization. Irrigation water will also be analyzed for potability (total coliforms and E. coli). Bacteria belonging to the Enterobacteriaceae family isolated from the samples will be submitted to identification (gender and species) using the MALDI-TOF-MS technique. Irrigation water samples will also be submitted to enumeration of total coliforms and E.coli. The Salmonella strains isolated from different samples will be submitted to clonal identity tests (PFGE) and serology, as indicators of possible routs of dissemination of the pathogen in the fields of production. This project will be developed within the scope of the Food Research Center (FoRC/FAPESP/CEPID 2013/07914-8) and project PROSA - Produce safety: a comparative analysis of consumer exposure to pathogens and extended spectrum ß-lactamases (ESBL) producing bacteria in different farming practices and climate zones (FAPESP/IDF- Denmark 2017, in elaboration), and will be supported by Dr. Michelle Danyluk,from University of Florida (USA) and Dr. Issao Ishimura, from Unidade de Pesquisa e Desenvolvimento em Agricultura Ecológica - APTA São Roque, Secretaria de Agricultura e Abastecimento de São Paulo. (AU)