Araújo, F.1; Lima, W. R. de 2; Becker, V.1; Araújo, A. L. C.2, 3; Camargo-Valero M. A.4, 5
1 Laboratório de Recursos Hídricos e Saneamento Ambiental, Departamento de Engenharia Civil, Centro de Tecnologia. Universidade Federal do Rio Grande do Norte, 59078970, Natal, RN, Brazil. 2 Programa de Pós-Graduação em Engenharia Sanitária, Departamento de Engenharia Civil, Centro de Tecnologia. Universidade Federal do Rio Grande do Norte, 59078970, Natal, RN, Brazil. 3 Department of Natural Resources, Federal Institute for Education, Science and Technology of Rio Grande do Norte. Natal-RN, Brazil. 4 School of Civil Engineering, University of Leeds, Leeds LS2 9JT, UK. 5 Departamento de Ingeniería Química, Universidad Nacional de Colombia, Sede Manizales.(free)
Cyanobacteria and their toxins can commonly occur in waste stabilization ponds (WSP). This study evaluated phytoplankton communities in facultative and maturation ponds of seven WSP systems in northeast of Brazil, with particular interest given to the presence of cyanobacteria and microcystin. During this study, cyanobacteria were dominant in most of tested samples, but microcystin concentrations were always bellow 0.2 g.L-1. The WSP evaluated had a low efficiency in the removal of organic matter and nutrients. Although concentrations of cyanobacteria decrease from facultative to maturation ponds, final effluents may be a source of contamination to water bodies with cyanobacteria and their toxins.