Prioritization based on risk assessment to study the bioconcentration and biotransformation of pharmaceuticals in glass eels (Anguilla anguilla) from the Adour estuary (Basque Country, France)

Metabolomics to Study the Sublethal Effects of Diazepam and Irbesartan on Glass Eels (Anguilla Anguilla)

“…However, before we can confirm what our results suggest, we believe it is important to support this hypothesis using other methodological approaches that allow us to see the same effect at different physiological levels. For now, we can say that the combination of the results present in this and our previous work (Alvarez-Mora et al, 2022) gives us a broad picture of the impact that contaminants can have on glass eels from their fate within the glass eel organism to the sublethal effects, supports the implementation of metabolomics as a complementary tool in the evaluation of toxicological effects, and provides further evidence of the need to improve the efficiency of wastewater treatment processes, especially for the contaminants of emerging concern.…”

“…Finally, although the role of controls is to cancel most of the unwanted effects, we could also consider some confounding effects based on the use of wild eels. For instance, some contaminants may have not been thoroughly removed during the acclimation period (Alvarez-Mora et al, 2022), and therefore, the observed effects might be the consequence of Fig. 4.…”

“…In 2017, the three main wastewater treatment plants (WWTPs) that release their effluents into the estuary were studied and the quantification of contaminants included in the Water Framework Directive (WFD) was performed (Cavalheiro et al, 2017). More recently, the environmental risk assessment study led to the identification of diazepam, irbesartan and propranolol among the most remarkable CECs released by the WWTP of Bayonne (Alvarez-Mora et al, 2022). Precisely, the anxiolytic diazepam and the antihypertensive irbesartan were two of the compounds found at the highest concentration (~3 ng⋅mL − 1 ) and it was also proven by a 7-day exposure experiment that they have a bioconcentration potential of up to 10-fold (BCF = 10).…”

“…Therefore, as a follow-up to the previous study on the fate of CECs in glass eels, the aim of this work was to investigate the effects of diazepam and irbesartan on the glass eel metabolic system. As mentioned above, irbesartan and diazepam were selected based on the observations of previous environmental risk assessment studies (Alvarez-Mora et al, 2022), and the exposure experiments were designed taking into account both previous studies (Alvarez-Mora et al, 2022;Ziarrusta et al, 2019) and the specificities of glass eels (Figueiredo et al, 2020;Liu et al, 2019). The exposure experiments were carried out at the concentrations found in the effluent in the previous study, which would refer to the worst-case scenario (Lopez-Herguedas et al, 2021), as we do not take into account the dilution factor that may be present in the estuary.…”