Freshwater amphipods (Gammarus pulex/fossarum) and brown trout as bioindicators for PFC contamination with regard to the aquatic ecological status of a small stream

Abstract

Abstract Background Per- and polyfluorinated chemicals (PFC) have been in use for more than 60 years. As a result of their high thermal and chemical stability, they have found numerous applications in industrial processes. However, PFC also commonly show disadvantageous properties such as persistence and ubiquitous presence in the environment. The issue of PFC contamination of surface water is addressed in this publication. One aim of this study was to find a potential bioindicator for PFC contamination of small streams, and a second aim was to determine the aquatic ecological quality of such a stream. Standardized methods were used including structural quality mapping of a watercourse, the PERLODES method and electrofishing in four study sections of the stream. PFC contamination was determined in freshwater amphipods (Gammarus pulex/fossarum) and brown trout. Results This study shows that PFC originating from water contamination can be detected both in amphipods and in internal organs of brown trout. The fingerprints in these two species differ considerably from one another. The highest concentrations of PFC were found in the liver and kidneys of brown trout. The methods used in this study also show that the four study sections of the small stream tested fail to achieve the “good” ecological status required by the Water Framework Directive. In particular, this is due to inadequate benthic invertebrates. Conclusions Even though it is not possible to determine a causal relationship between the ecological status of the small stream and the detection of PFC in aquatic organisms, appropriate measures must be developed and applied to reduce the spreading of PFC in the environment. In addition to the brown trout, freshwater amphipods proved to be useful as a bioindicator for PFC contamination of streams. In the future it will be necessary to observe whether the number of species in the benthic invertebrates continue to decline.