Microbiological quality of lettuce irrigated with treated wastewater

It is necessary to search for alternative sources of water where the use of potable water is not required. The reuse of treated domestic effluent is an alternative for crop irrigation. This research was conducted using a complete randomized block design in a 3 x 3 factorial scheme with five replications, in a protected environment at the Federal University of Sergipe. This study was designed to evaluate the microbiological quality of Baba de Verão (Lactuca sativa) irrigated with different concentrations of effluent (0, 50 and 100%) in two cycles and three irrigation depths, corresponding to 75, 100 and 125% field capacity. The leaves were submitted to microbiological analysis to verify if they were contaminated by treated wastewater used for irrigation of the crop. The analyzed variables were thermotolerant coliforms and Salmonella. The microbiological quality of lettuce was classified according to the standards required by the National Sanitary Surveillance Agency for the consumption of fresh vegetables. Treated domestic wastewater can be considered a possible source of water for lettuce when water is applied to the soil in proximity to the root system of the crop.