## 3 Derivation of Water Quality Criteria and Relevant Fish Assay
### European Commission
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Acute/ Chronic** & **Test Guideline** & **Test Species** & **Exposure Stage** & **Test Duration** & **Endpoints** \\ \hline \multirow{4}{*}{Acute} & TG 203 [40] & _Danio rerio_ & Adult & 4 days & Survival, abnormality \\ \cline{2-6}  & TG 236 [12] & _Danio rerio_ & Embryo & 4 days & Survival, abnormality, heartbeat \\ \hline \multirow{4}{*}{Acute} & \multirow{4}{*}{TG 210 [13]} & _Oncorhynchus mkiss_ & & 60 dph \({}^{1}\) & Hathing, survival, abnormality, behavior, \\ \cline{2-6}  & TG 210 [13] & _Pimephales promelas_ & Embryo & 28 dph\({}^{1}\) & abnormality, behavior, \\ \cline{2-6}  & & _Danio rerio, Oryzias latipes_ & & 30 dph \({}^{1}\) & length, weight \\ \cline{2-6}  & & _Cyprinus carpio_ & & 8–9 days & \\ \cline{2-6}  & & _Oncorhynchus mynkiss_ & & 50–55 days & Hathing, survival, abnormality, behavior, \\ \cline{2-6}  & TG 212 [14] & _Pimephales promelas_ & Embryo & 8–9 days & \\ \cline{2-6}  & & _Brachydanio rerio_ & & 8–10 days & growth (length, weight) \\ \cline{2-6}  & & _Oryza latipes_ & & 13–16 days & \\ \cline{2-6}  & & _Oncorhynchus mynkiss, Dario_ & & & \\ \cline{2-6}  & TG 215 [42] & _ rerio, Oryzias latipes_ & & 28 days & \\ \cline{2-6}  & & _Oryza latipes_ & & & \\ \cline{2-6}  & TG 234 [15] & _Dario rerio, Gasterostreus_ & Embryo & 60 dph \({}^{1}\) & Hathing, survival, growth (length, weight), \\ \cline{2-6}  & & _aculeatus_ & & & \\ \cline{2-6}  & TG 240 [43] & _Oryza latipes_ & 12–16 wpf \({}^{2}\) & 19 weeks & Survival, growth (length/weight), organ \\ \hline \multirow{4}{*}{Screening tool for chronic toxicity} & TG 229 [41] & _Pimephales promelas_ & 18–22 wpf \({}^{2}\) & & \\ \cline{2-6}  & TG 229 [41] & _[PERSON], Oryzias latipes_ & 14–18 wpf \({}^{2}\) & 21 days & Survival, appearance, behavior, fecundity, sex ratio \\ \cline{2-6}  & & _Pimephales promelas_ & 18–22 wpf \({}^{2}\) & & \\ \cline{2-6}  & TG 230 [44] & _[PERSON], Oryzias latipes_ & 14–18 wpf \({}^{2}\) & 21 days & Survival, appearance, behavior, sex ratio \\ \hline \hline \end{tabular} \({}^{1}\) Days post-hatching (dph). \({}^{2}\) Weeks post-fertilization (wpf).  
\end{table} 
Table 3: Test guidelines for fish in Organisation for Economic Co-operation and Development used in the derivation for Environmental Standard Quality recommended by European Commission. Juvenile or adult fish assays are also mentioned; representative methods are the acute test for adult fish with 96 h of exposure (OECD TG 203) and chronic tests on juvenile fish with at least 4 weeks of exposure (OECD TG 215) [15; 42; 43]. For sexual development or reproduction, both the 60-day TG 234 sexual development test and the one-generation reproduction test (OECD TG 240) using _O. latipes_ are considered chronic toxicity tests [15; 43]; these two tests are mainly focused on endpoints such as gonadal histology, vittellogenin concentration, or sex hormone levels. The short-term tests, lasting less than 4 weeks, can be used to support the toxicity data for deriving the EQS in the European Commission, but are deferred from the priority lists of chronic toxicity tests (OECD TG 229 and TG 230) [3; 41; 44].