Acute Toxicity in Urban Area of Água Boa Stream Watershed, MS, Brazil

ABSTRACT The watershed of Água Boa Stream (Dourados/MS) suffers great anthropic influence, such as urban and industrial. Taking into consideration its importance for maintenance of fauna, flora, industry and local population, this study aimed to: assess the toxicity of its waters during the dry and rainy seasons of 2013, near the source to its mouth, through acute toxicity essays with D. similis and D. rerio, as well as physical, chemical and heavy metal concentration analyses. The results showed spatial and temporal variability of the analyzed parameters. Furthermore, a toxic effect was found at point 02 for D. rerio in both periods. The analyses confirmed the critical situation of degradation of the aquatic environment studied, and warns that precautions should be taken. Therefore, it is suggested that greater supervision by environmental agencies, as well as public awareness of the issue of waste and residues in the water body, in order to avoid its degradation.