THE DISCHARGE OF EFFLUENTS AND THE CONTAMINATION BY TOXIC METALS AND ORGANIC MATTER IN BASTIANA LAKE, CEARÁ, BRAZIL

• Autor(a) principal: Souza, Anastácia O
• Data de Publicação: 2016
• Outros Autores: Castro, Antônio Hermeson S, da Silva, Nataniela, Braga, Erika A S, Millhome, Maria Aparecida Liberato
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Holos
• Texto Completo: http://www2.ifrn.edu.br/ojs/index.php/HOLOS/article/view/4352
• topic: Urbanization; wastewater; aquatic environment; metals; nutrients

In recent years, the process of urbanization has been growing in Iguatu, important city of the semi-arid region of Brazil. This process has influenced the quality of aquatic environments due to effluent discharge and the emission of pollutants. Iguatu has modern and efficient sewage treatment system, but only 15% of the population benefits. This paper aimed at the determination of 9 metals and 12 physical-chemical parameters to characterize of Bastiana Lake-CE and to evaluate the influence of effluent discharge. The results of the analysis of toxic metals showed presence of Zinc (Zn) and manganese (Mn) at levels above of maximum limits established by Brazilian legislation. Exposure to Mn can affect the IQ (Intellectual quotient). Water samples showed high concentration of organic matter (BOD), nitrogen, phosphorus, soluble substances hexane and presence of floating materials. The level of nutrients (N and P) classified the lake as eutrophic and hypereutrophic and may cause risk to human health.  Results suggest that actions must be taken by government agencies to prevent the complete degradation of Lake Bastiana (Ceará, Brazil).