BIOMONITORING OF SURFACE WATER TOXICITY RELATED TO URBAN AND INDUSTRIAL WASTEWATER RELEASE

Water toxicity was biomonitoried by Tradescantia pallida, relating the results to physicochemical and qualitative analysis. Two clusters were formed by hierarchical analysis of micronuclei percentage (MN), dissolved oxygen (DO), electrical conductivity (EC) and turbidity. The first cluster corresponded to a stream that receives urban untreated sewage, where the highest MN (6.1%) corroborated the physicochemical results (1.90 mg.L‑1 DO, 575.0 μS.cm‑1 and 115.6 NTU). The other cluster includes sampling sites with pollutants from agriculture, livestock and industry. Some of them presented high MN even with acceptable values of physicochemical parameters, according to the Brazilian legislation. So for a better quality information on water pollution monitoring it is essential to recognize the variables that affect the biotic components, in a holistic approach of aquatic ecosystem. In this sense the bioassay with T. pallida becomes a useful tool that can be applied in many tropical and subtropical regions, because of its widely distribution