Assessing the sources of high fecal coliform levels at an urban tropical beach

Abstract

Recreational water quality is commonly assessed by microbial indicators such as fecal coliforms. Maceió is the capital of Alagoas state, located in tropical northeastern Brazil. Its beaches are considered as the most beautiful urban beaches in the country. Jatiúca Beach in Maceió was found to be unsuitable for bathing continuously during the year of 2011. The same level of contamination was not observed in surrounding beaches. The aim of this study was to initiate the search for the sources of these high coliform levels, so that contamination can be eventually mitigated. We performed a retrospective analysis of historical results of fecal coliform concentrations from 2006 to 2012 at five monitoring stations located in the study region. Results showed that Jatiúca Beach consistently presented the worst quality among the studied beaches. A field survey was conducted to identify existing point and non-point sources of pollution in the area. Monitoring in the vicinity of Jatiúca was spatially intensified. Fecal coliform concentrations were categorized according to tide range and tide stage. A storm drain located in northern Jatiúca was identified as the main point source of the contamination. However, fecal coliform concentrations at Jatiúca were high during high tides and spring tides even when this point source was inactive (no rainfall). We hypothesize that high fecal coliform levels in Jatiúca Beach may also be caused by aquifer contamination or, more likely, from tide washing of contaminated sand. Both of these hypotheses will be further investigated.

Occurrence ofβ-Lactamase-Producing Gram-Negative Bacterial Isolates in Water Sources in Cali City, Colombia

“…The highest number of resistant isolates was obtained significantly to third-generation cephalosporins and β -lactamase inhibitors during the dry season, reaching values above 70%, especially in the artificial waters of the rainwater channel and in Intersector Canal (CVC) Sur. The resistance prevalence data of Gram-negative bacilli resistant to β -lactams were similar to those detected in the sewage system of the city of Rio de Janeiro [43] and other cities in Brazil [44]. These antibiotics are the most used in the treatment of infections caused by Gram-negative bacilli, which shows the selective pressure that is exerted on bacteria of fecal and natural origin.…”

“…Davino et al [44] and Delgado et al [45], analyzing the coliform counts in Jatiúca Beach, Brazil, and Bassaseachic Falls National Park, Mexico, respectively, reported that the fecal coliform count was higher during the wet seasons (May, June, and July) than during the dry seasons (November, December, and January), indicating water movement during higher temperatures [44–46].…”

Multidrug-Resistant Bacteria Isolated from Surface Water in Bassaseachic Falls National Park, Mexico

“…In contrast, the lowest total coliform counts were observed in summer and winter as lower rain/humidity and temperatures (not higher than 20 °C) are present ( Figure 3 C). Davino et al [ 29 ] reported similar results after analyzing the coliform counts in Jatiúca Beach, Brazil. These authors reported that the fecal coliform count was higher during the wet seasons (May, June, and July) than during the dry seasons (November, December, and January).…”