Bacteriological analysis of horticultural irrigation water

Abstract

This study analyzed the quality of water used for the irrigation of five crops based upon microorganism indicators of fecal contamination (group coliforms) and contamination by organic material (Pseudomonas aeruginosa) in both the water and in the irrigated food. The study also verified the decrease in the activity of these microorganisms by heterotrophic bacterial count before and after treatment with three different sanitizers. The presence of coliform (NMP > 1600) and Pseudomonas aeruginosa was observed in both the irrigation water and in the irrigated food, and the coefficient of variation (R2) revealed a strong correlation between the rates of contamination of the water and food. All of the sanitizers evaluated reduced the bacterial load of the food, especially sanitization with vinegar at 200 ppm, which, in addition to greatly reducing food contamination, is also considered a low-cost and toxicologically safe product, and therefore may be indicated for this purpose. Thus, the use of poor quality water in the irrigation of vegetables may directly contribute to food contamination, with serious implications for the health of consumers.