Presence of Aeromonas spp in Water from Drinking‐Water‐ and Wastewater‐Treatment Plants in México City

Abstract

The frequency of Aeromonas spp in three wastewater‐treatment plants (WWTPs) and two drinking‐water plants (DWPs) in México City was determined. Samples were taken throughout a year by the Moore's swab technique. A total of 144 samples were obtained from WWTPs and 96 from DWPs of both incoming and outflowing water. Aeromonas spp was isolated in 31% of the samples, from both kinds of sources. The technique used for the isolation of the pathogen was suitable for samples with high associate microbiota content and for those with a scarce microbial content. The presence of mesophilic‐aerobic, coliform, and fecal‐coliform organisms was investigated to determine whether there was any correlation with the presence of Aeromonas spp. Most samples from WWTP, which did not comply with the Mexican standards, had the pathogen, and some of the samples from the outflow of the DWP, which were within the limits set by the Mexican standards, also had Aeromonas spp. Most samples containing Aeromonas spp. had concentrations below 0.1 ppm residual chlorine, and the strains were resistant to 0.3 ppm, which supports the recommendation to increase the residual chlorine concentration to 0.5 to 1.0 ppm, as recommended by the Mexican standards.

Dynamics of Aeromonas species isolated from wastewater treatment system

“…Ribeiro et al (2010) Aeromonas species are the most common organisms reported in infections of burns exposed to contaminated water. However, Lamy et al Polluted aquatic environments can be considered a source of contamination for recreational waters and water used in the irrigation process (Villari et al 2000;Davies et al 2001;Uyttendaele et al 2004;Vally et al 2004;Villarruel-Ló pez et al 2005;Daskalov 2006;Dwivedi et al 2008). Besides the determination of indicator bacteria, it is important to understand the distribution of potentially doi: 10.2166/wh.2010.140 pathogenic bacteria in a given ecosystem that could affect natural water used for human contact or consumption (Nagvenkar & Ramaiah 2009).…”

Aeromonas presence in drinking water from collective reservoirs and wells in peri-urban area in Brazil

“…Thus, some authors consider that these organisms should be a sanitary quality indicator (7,19,21,24). Moreover, Aeromonas hydrophila is listed in the first and second Contaminant Candidate List (CCL1 and CCL2) by the US Environmental Protection Agency -USEPA (26), linking these organisms to public health adverse outcomes.…”

“…These organisms are largely distributed in several water sources such as rivers, lakes, wells, sewage, wastewaters and drinking water supplies (19,24).…”

“…The presence of these organisms in drinking water supplies, including in those chlorinated, is a reason to public health concern due to their capacity to produce toxins (8,20,21), to colonize biofilms (5,20) and to resist to chlorine (3,24). Ghenghesh et al (10) (24) detected Aeromonas in 31% of the samples from drinking water plants in Mexico City.…”

“…Ghenghesh et al (10) (24) detected Aeromonas in 31% of the samples from drinking water plants in Mexico City. Razzolini et al (19) detected Aeromonas in chlorinated water reservoirs and drinking water fountains in the city of São Paulo.…”