Density of Enterococcus sp in recreational waters and beach sand in São Vicente-SP, Brazil and its relationship to abiotic parameters

DOI: 10.15343/0104-7809.2012364587593

Abstract

cities attract a large number of tourists for their beautiful landscape and recreational activities, increasing the municipalities’
income source. Thus, a need is clear for the establishment of beach quality monitoring programs to ensure bathers health. Although
there is an effective monitoring program for recreational waters in Brazil there are no programs to certify the quality of beach sands. In
this sense, the aim of this work was to analyze the density of bacteria from the genus Enterococcus in both sand and water from two
beaches from São Vicente, São Paulo (Brazil) and correlate these densities to abiotic parameters such as: temperature, salinity, particle
size, organic matter and tides). Water and sand samples were collected during February 2006 on the beaches of Gonzaguinha e
Ilha Porchat and bacterial densities were determined by membrane filter technique. Temperature and salinity were measured in situ
with a thermometer and a refractometer while particle size and organic matter were determined according to methods described by
Suguio and Dean. There were significant differences between densities found in water and sand (p=0.004), being approximately 20
times higher in Gonzaguinha’s beach sands. Similar results were found for Ilha Porchat beach samples, being the densities found in
sand 3 times greater than those found in water. Both beaches showed a negative correlation between bacterial densities and salinity
and temperature, suggesting a deleterious effect of these parameters on the bacterial community. On the other hand, no correlation
was found between organic matter and particle size and bacterial densities. This work demonstrates that there is a great necessity
for monitoring beach sand since the evaluation of beach quality is an important part of integrated coastal management programs.