Metodología para derivar niveles guía para la protección de la biodiversidad acuática

Abstract

The different anthropic activities (e.g., agriculture, industry, urbanization) incorporate contaminant compounds to aquatic ecosystems, which could affect directly and/or indirectly the biota. Management of water resources seeks to include technical-scientific criteria for decision making, promoting the conservation and preservation of these ecosystems. Considering this context, the definition of guide level values of water quality arises as a tool for aquatic biota protection. The aim of the present study was to describe the methodology of derivation of guide level values for aquatic biodiversity protection, which emerged from the work of the group Water Quality and Guide Levels for the Protection of Aquatic Biodiversity, of the Aquatic Ecosystems Evaluation and Monitoring Network (REM.AQUA-CONICET). It incorporates approaches used internationally, applying a combination of probabilistic tools based on the species sensitivity distribution (SSD), as well as the use of conservative values of extrapolated effect concentrations and associated with assessment factors, according to the available data. The methodology details the type, quantity and quality of ecotoxicological data to be considered for derivation, in addition to the steps to be followed in a flowchart. It shows the sequential decisions for obtaining the guide level values according to the information availability. The methodology also looks to generate type A and B guide values, according to the uncertainty associated with the obtaining of them. The methodology is exemplified through the species sensitivity distribution approach for atrazine and through assessment factors for the case of 2,4-D. Finally, the scope and limitations of the methodology are discussed, including those associated with the importance of incorporating a wide quantity of information of native species from different aquatic ecosystems of Argentina.