Modeling microbiological quality dynamics of Suquía river in Córdoba, Argentina.

PAVANJ.V. ; BARRIL P,; MARTINEZ, L; GIORDANO M; MASSACHESSI, G; FERREYRA, L; ISA MB; IBARRA G; RÉ V.; NATES S

Madrid

Conferencia; V International Conference on Environmental, Industrial and Applied Microbiology (BioMicroWorld2013),; 2013

Water is one of the main sources of human exposure to microbiological hazards. Regulatory standars in therms of fecal indicator to assess the microbiological quality of water not necessarily predict the presence of pathogens. Enteric viruses, which are generally more resistant than bacteria, are not usually detected. Group A rotavirus (RVA) and norovirus (NoV) cause gastroenteritis and are shed in high numbers through feces of infected individuals, being highly stable in the environment. RVA is not under national vaccination program and there is no available vaccine for NoV. The aim of this work was to characterize Suquía river water quality which crosses the city of Córdoba in Argentina, in order to evaluate its dynamics through the city during different seasons. Suquía water flow is 10m3/second subject to a seasonal fluctuation: very high flow during the wet season (WS) 24m3/second and very low during the dry season (DS) 1.5m3/second. Eleven points along the river were selected along it crosses the city (37.8 km), some were located at recreational areas. Seasonal monitoring was performed during the year 2010. Six points (P) were directly located on the city, while out of the other five, one corresponded to San Roque (SRP), where the river borns, and four when it leaves the city, downstream of the wastewater treatment municipal plant of Bajo Grande (BGP). Data from the year-long monitoring campaign of the Suquía River were analyzed to statiscally correlate physicochemical and microbiological variables, the seasonal and longitudinal variations of the water quality and determine the similarity between study sites. The measured variables included temperature, pH, total hardness, chloride, dissolved oxigen, chemical oxigen demand, biological oxigen demand, nutrients, total and thermotolerant coliforms. For viral detection surface water was concentrated 100X by polyethilenglycol precipitation. RVA and NoV detection were carried out by RT-nested PCR. For statistical inference nonparametric Kruskal Wallis One-Way ANOVA for the multiple comparison of variables according the monitorig point and Mann-Whitney U test for comparison WS vs DS were performed. In addition, data sets were sujected to multivariate statistical analysis: cluster analysis (CA) and discriminant analysis. A dendrogram was built using the variables with statistical inference (p