1. Federal University of Paraíba, Civil Engineering Dept; Laboratory of Sanitary & Environmental Engineering, Av Aprigio, 882- CEP: 58109-001, Campina Grande, Paraíba, Brazil
2. State University of Paraíba. Center of Biological Science. Av das Baraúnas s/n. CEP: 58109-753, Bodocongó, Campina Grande, Paraíba, Brazil