Evaluation of sanitary quality of lettuce (Lactuca sativa, L.) irrigated with reused water in comparison with commercialized lettuce

  • Antonio Claudio Testa Varallo UNITAU
  • Joseane Marioto de Souza UNITAU
  • Simone Sano Rossi de Rezende UNITAU
  • Claudinei Fonseca Souza UFSCar
Keywords: reuse water, irrigation, coliforms, lettuce (Lactuca sativa, L.)

Abstract

Inadequate use of water resources reduces their availability and therefore, research focused on their reutilization is required. This work evaluated the sanitary quality of lettuce irrigated with reused water in comparison with samples of lettuce commercialized in Taubaté (SP) market. An experiment was developed in a greenhouse with three beds of lettuce irrigated with reused water and three beds of lettuce irrigated with urban water supply. After lettuce biological cycle had been completed, lettuce samples were collected from the beds (irrigated and non-irrigated with reused water) and from samples of lettuce commercialized in the city market that were analyzed in the laboratory. The analyses were done using the multiple tubes methodology. The results showed that the samples from lettuce irrigated with urban water supply were not contaminated by either total or thermotolerant coliforms while samples of irrigated lettuce with reused water were contaminated by total coliforms. Samples from commercialized lettuce were contaminated by both kinds of coliforms. Results indicated that the application of reused water for agricultural purposes should occur only after carefully treatment to allow a safe use and to contribute to the water use sustainability.

Author Biographies

Antonio Claudio Testa Varallo, UNITAU
Teacher Master of Department of Civil Engineering - UNITAU
Joseane Marioto de Souza, UNITAU
Environmental and Sanitary Engineer
Simone Sano Rossi de Rezende, UNITAU
Technique in Chemical
Claudinei Fonseca Souza, UFSCar
Researcher Assistant Professor, PHd. of Department of Natural Resources and Environmental Protection - CCA/UFSCar.
Published
22/08/2011
Section
Papers