Water contamination by Enterococcus at the beaches of the municipality of Sao Luis, Maranhao State, northeastern Brazil/ Contaminacao por Enterococcus da agua das praias do municipio de Sao Luis, Estado do Maranhao

The aim of this study was to evaluate the hygiene and sanitary conditions of the beaches of the city of Sao Luis, using Enterococcus as the indicator. Two distinct periods were studied: the rainy and drought seasons. The samplings were performed fortnightly during the rainy season and weekly at dry season. Water pH was measured at the sampling site, and microbiological analysis was performed at the laboratory using the multiple-tube method, as recommended by the American Public Health Association . APHA (1995). The pH was found to be within normal levels, between 7 and 8, for all examined beaches. High levels of Enterococcus, between [10.sup.2] and [10.sup.3] MPN 100 m[L.sup.-1], were found during the drought season, reaching [10.sup.5] MPN 100 m[L.sup.-]1 in the rainy season. It was concluded that the beaches of Ponta da Areia and Calhau were characterized as improper for swimming at the examined periods, while the Olho d'Agua and Aracagi beaches were suitable. Key words: beaches, Enterococcus, microbiologic analysis. O objetivo deste estudo foi avaliar as condicoes higienico-sanitarias das praias do municipio de Sao Luis, utilizando os Enterococcus como indicador. Foram avaliados dois periodos distintos, estacao chuvosa e seca. A amostragem foi realizada quinzenalmente na estacao chuvosa e semanalmente na estacao seca. Aferiu-se o pH no local da coleta e no laboratorio, realizou-se analise microbiologica de acordo com a metodologia dos tubos multiplos, conforme preconiza a American Public Health Association--APHA (1995). O pH mostrou-se dentro do padrao, com indices entre 7 e 8, em todas as praias. Constataram-se altos indices de Enterococcus, da ordem de [10.sup.2] a [10.sup.3] NMP 100 m[L.sup.-1] no periodo seco, chegando a [10.sup.5] no periodo chuvoso. Conclui-se que as praias Ponta da Areia e do Calhau se caracterizaram como improprias para banho nos periodos avaliados, enquanto as praias Olho d'Agua e Aracagi se enquadraram como proprias. Palavras-chave: praias, Enterococcus, analise microbiologica.