Assessing the aquatic toxicity and environmental safety of tracer compounds Rhodamine B and Rhodamine WT

Tracer tests represent a well-established method for delineating key environmental processes in various media and engineered systems. Tracers like Rhodamine B WT are frequently applied due to their strong fluorescence even at low concentrations.. However, lack of ecotoxicological data, limit values these tracers cannot be determined. This study fills this critical data gap by providing ecotoxicity using battery short-term standardized tests, including growth rate inhibition with algae (Raphidocelis subcapitata) lethality crustaceans (Daphnia magna) zebrafish (Danio rerio) embryos, estimating EQS surface water. For B, the effective lethal concentration (EC50 LC50) –causing 50% toxicity were range 14–24 mg/L. WT, no statistically significant effects observed (p<0.05) tsted concentrations (up 91, 100 200 mg/L algae, fish respectively). Thus all tested organisms, was more toxic than (more 14 times R. subcapitata, 5.6 D. magna, 15 rerio embryos,based on EC10 LC10 values). These results signify that read-across assessments obtained is not advisable WT. The annual-average quality standard (AA-QS) maximum allowable (MAC-QS) found 140 µg/L, respectively. corresponding estimated >91 µg/L >910 (MAC-QS). Hence, below or 910 respectively, expected pose risk aquatic freshwater life case intermittent discharges, e.g. tracer experiments released streams.