Decay of pathogens (indicators of Escherichia coli and Salmonella spp.) in soil due to the application of reuse water

Decaimento de patógenos (indicadores de Escherichia coli e Salmonella spp.) no solo devido a utilização de água de reúso

Abstract

Reuse water is defined as the reuse of water from treated effluents, it requires careful monitoring to avoid damage to environmental health. This study evaluates the decay of Escherichia coli and Salmonella spp. bacteria in soil irrigated with reused water for agricultural reuse, without damaging public or environmental health. The decay of Escherichia coli and of Salmonella spp. was verified using the Filter Membrane method SS AGAR culture medium was used. The decay curves over time were made using the Sigmaplot program. Each experimental group had 4 pots (one group irrigated with recycled water and the other with drinking water), two pots containing vegetation cover and two containing only soil. In crops irrigated with reused water, the survival time of Salmonella spp. was double compared to the others, and E. coli survival did not vary between groups. Pots with bare soil irrigated with uncontaminated reused water showed a faster decline in Salmonella spp. For agricultural reuse, irrigation must be done by drip and with the use of personal protective equipment. It is essential to create national legislation to protect public and environmental health.

Keywords: agricultural reuse; decay analysis of microorganisms; public health