Biochemical and genotoxic biomarkers in Atherina boyeri to evaluate the status of aquatic ecosystems

Transitional water ecosystems, like brackish coastal lagoons, provide important services but are subjected to several anthropogenic impacts that can initially lead to biodiversity modifications and then to critical alterations of ecosystem processes. Assessment and monitoring of the health status of these ecosystems is extremely important. This study reports the case study of “Capo Peloro” lakes (southern Italy), where ecotoxicological biomarkers in the key fish species Atherina boyeri have been used to reveal potential contamination in a transitional water ecosystem. The goal was to detect changes that occurred after the summer season, when the surrounding human population significantly increases, with the consequent enhancement of anthropic pressures. Lake Trasimeno, a reference protected site, was also selected. This study is the follow-up of a previous one carried out in the same environment reporting biomarkers employed on the copepod species Paracartia latisetosa, on which Atherina boyeri feeds. The main aim of the present study was to test the responses given by the same type of contamination in a planktivorous fish species, which occupies a higher trophic level. Several biochemical and genotoxic biomarkers were evaluated: Acetylcholinesterase (AChE), Benzo(a)pyrene-monooxygenase (BPMO), Polycyclic Aromatic Hydrocarbons (PAH) metabolites in bile, Erythrocytic Nuclear Abnormalities (ENA) assay. This study confirms the contamination already shown in P. latisetosa from pesticides and carbamates, and/or polycyclic and polyhalogenated aromatic hydrocarbons, heavy metals, surfactants in both “Capo Peloro” lakes. A higher concentration of contaminants was demonstrated in early autumn with respect to the summer season, due to enhanced anthropogenic activities around and on the lakes. This study highlights that, although “Capo Peloro” lakes and Lake Trasimeno are protected areas, they are affected by environmental degradation. This study also confirms the benefits gained with a biomarker approach in monitoring transitional water ecosystems