Sanitary quality and production of lettuce production irrigated with treated domestic sewage

Abstract The use of treated wastewater in the agriculture provides water to soil and the vegetables, nutrients and organic material, which preserve the land and act as organic fertilizers; however, they might cause contamination of the final product. In the current research we studied the lettuce irrigated (Lactuva sativa L) with water from a well in land without fertilization (T1) and with mineral fertilization (T2) and compared the productivity and the sanitary quality of the lettuce irrigated with water from well and with organic manuring (T3), with fertirrigation made with effluents of treated domestic wastewater in polishing lakes (T4) and decanted influent (T5). The results showed better productivity during the two experiments in the treatment with reused water, being better in the lettuce irrigated with the T5 treatment. The T4 presented médium concentrations of termal tolerant coliforms within the recommendation of the OMS for irrestricted irrigation: ( < 1.000 UFC 100 mL), < helminthes egg L-1), although it presented higher pH values of all influents (8.7 and 9.0); The T5 was the only treatment with effluent which did not reach either microbiological or parasitological conditions for the irrestricted irrigation.