Abstract
This study evaluated the efficiency of two bioindicators, fecal coliforms and ecotoxicity tests, set out in CONAMA Resolution 274/00 and CONAMA Resolution 357/05, in assessment of water quality. For this study, Lake Paranoa, Federal District of Brazil, was chosen, since it is a water body directly contaminated by effluents from a sewage treatment plant. Four sampling points were chosen in accordance with the map of recreational water quality published weekly by CAESB/DF, after analysis of fecal coliforms. Samples from these points were collected for 6 months and tested on Danio rerio fish (acute toxicity) and on the microcrustacean Ceriodaphnia dubia (acute and chronic toxicity), besides measuring chemical and physico-chemical parameters. The data obtained show great consistency between the observed biological parameters, suggesting that in this urban aquatic environment, under great anthropogenic pressure, the fecal coliform bioindicator seems to be more restrictive and enough to evaluate the safety of surface water.
Highlights
The evaluation of water quality has been adopted as one of the main criteria in establishing uses for any aquatic environment
The results of assays with Ceriodaphnia dubia showed that in February 2008 chronic toxicity was observed with water samples from points 2 and 3; in March 2008 water from point 2 showed acute toxicity, and the other sampling points showed an absence of toxicity during the three months (February, March and May) when we accomplished analysis with this microcrustacean
According to CONAMA Resolution no. 357, this would mean a satisfactory and unsuitable level, respectively, disagreeing with the classification given to Paranoá Lake, which stands at 2
Summary
The evaluation of water quality has been adopted as one of the main criteria in establishing uses for any aquatic environment. Biological Sciences undergone such intense alterations that, in many cases, there are high levels of environmental degradation that have led to numerous adverse effects and the potential extinction of aquatic species, which do not succeed in recovering their losses in the altered environment (SEITZ; POULAKIS, 2006; HEWITT et al, 2006; DOMÍNGUEZ-DOMÍNGUEZ et al, 2007) In this context, the use of biological indicators to evaluate water quality has become an important tool, concerning to protecting human health and preserving and maintaining life in the environment (VAN DER SHALIE et al, 1999; MARTINS et al, 2007)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
