Environmental benchmarks based on ecotoxicological assessment with planktonic species might not adequately protect benthic assemblages in lotic systems
| Autor: | Joana Luísa Pereira, Ana Ré, Joana I. Santos, Tânia Vidal, Fernando Gonçalves, Libânia Queirós, Nelson Abrantes |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
Pollution
Conservation of Natural Resources Environmental Engineering River ecosystem Lead chloride 010504 meteorology & atmospheric sciences media_common.quotation_subject Fresh Water 010501 environmental sciences Ecotoxicology 01 natural sciences Freshwater ecosystem Risk Assessment Benthos Species Specificity Standard chemicals Environmental Chemistry Animals Ecosystem Oligochaeta Waste Management and Disposal 0105 earth and related environmental sciences media_common Ecology fungi Contamination Plankton Benchmarking Benthic zone Species sensitivity distribution Environmental science Benthic vs planktonic organisms Water Pollutants Chemical |
| Popis: | Freshwater ecosystems face widespread diffuse and point-source contamination. Species Sensitivity Distributions (SSDs) have been used as a tool to determine chemical concentration benchmarks that represent protective levels for most species in the environment. Here we used a SSD approach to assess on the adequacy of standard planktonic organisms to reflect the response of benthic communities, critically supporting the structure and function of lotic ecosystems. For the purpose, SSDs reflecting non-lethal responses of standard planktonic and selected benthic organisms were built based on EC50 values (collected in the literature or estimated following testing herein) regarding three model contaminants: potassium dichromate (PD), 3,5-dichlorophenol (DCP) and lead chloride (LC). The derived HC5 estimates were discriminatory between chemicals and the uncertainty associated with the estimate was remarkably low. The HC5 estimates with corresponding uncertainty were generally within the same order of magnitude for the three chemicals tested, with better discrimination between chemicals regarding their hazardous potential being achieved for benthic organisms: DCP was clearly less hazardous than PD, but LC tends to be as hazardous as PD and DCP (assuming the confidence interval ranges). Moreover, benthic communities were more sensitive to both DCP and PD, in this later case the HC5 being lower by more than one order of magnitude than that found for planktonic communities; for LC, confidence intervals overlapped, preventing a feasible assumption regarding differential sensitivity of the compared communities. Microphytobenthos was highlighted as the most sensitive group to the three tested chemicals in SSDs covering the benthic compartment, while SSDs with planktonic organisms did not consistently show trends in sensitivity ordering. Overall, our results suggest that protective benchmarks retrieved from SSDs built with the responses of standard planktonic organisms (which are the most commonly used for regulation purposes) do not adequately protect benthic communities. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|