overview_calux_assays.xlsx

Two in vitro chemically activated luciferase gene expression (CALUX) reporter gene assays were applied to assess the activation of the estrogen and aryl hydrocarbon receptors (ERα and AhR), respectively. The two CALUX assays represent defined toxic modes of action and can serve as proxies for specific sources of pollution (van der Burg et al., 2013; De Baat et al., 2020). Estrogen receptor agonism (ERα CALUX), indicative of endocrine disruption, was used as a proxy for wastewater pollution (Välitalo et al., 2016) and aryl hydrocarbon receptor agonism (PAH CALUX), indicative of the induction of xenobiotic metabolism, as a proxy for industrial pollution (Neff et al., 2005). The ERα and PAH CALUX assays were performed by the BioDetection Systems laboratory (Amsterdam, The Netherlands) as described by De Baat et al. (2020). The effects of the extracts in the assays were expressed as bioanalytical equivalents (…EQ/L) of the reference compounds of the assays using the estimated sampled water volume of the passive samplers (Table 1).