The assessment of feeding inhibition in Folsomia candida (collembola) as an endpoint for ecotoxicological waste characterization
2010 The assessment of feeding inhibition in Folsomia candida (Collembola) as an endpoint for Ecotoxicological waste characterization GARCIA GERONASSO João Victor (Brazil) email@example.com
Organisation: University of Coimbra, Coimbra (PT) - Autonome University of Barcelona (SP) Supervisor : José Paulo Sousa (UC) & Xavier Domene (UAB)
Summary: In order to understand waste properties and their impact upon the environment, ecological risk assessment frameworks have been developed and proposed in a couple of European countries. Since chemical analyses alone are considered not suitable for this task, several bioassays are being employed to fill this gap. The usual endpoints are related to lethality and effects over reproduction of non-target organisms. However, these tests often require extensive effort in terms of time and handling. As a consequence, the suitability of new endpoints at physiological and behavioral levels is being conceived. It has been suggested that the feeding inhibition in the collembolan Folsomia candida represents a reliable tool for the estimation of organic waste toxicity. In the present study, this parameter is evaluated using 9 wastes from different origins and compared with the results obtained from the standardized F. candida reproduction test. Feeding and reproduction EC20 and EC50 values were calculated, as well as the LC50, for each one of the wastes. As a result, it was generally observed that feeding behavior was affected at substantially lower concentrations than reproduction and lethality. No correlations were found between the outcomes of both methods. However, in 8 out of 9 wastes tested, feeding inhibition detected the toxicity pointed out by the traditional method. In conclusion, feeding inhibition should not be employed as a direct substitute for the reproduction endpoint as it does not give specific dose-effect responses nor comparable ECx values. Nevertheless, the idea of validate this endpoint as a warning indicator for waste ecotoxicity seems to be plausible with further research.