5H-Cyclopenta[h]quinazoline, 6,6a,7,8,9,9a-hexahydro-7,7,8,9,9-pentamethyl-

Long-term toxicity to fish

Description of key information

The long-term toxicity to fish (Danio rerio) was examined in a study in accordance with OECD TG 210 and in compliance with GLP criteria. In this study, groups of fish (4 replicates of 20 animals) were exposed to nominal concentrations of 0 (control), 0.00922, 0.0230, 0.0576, 0.144, and 0.360 mg/L for 31 days under flow-through conditions. Test substance analysis was performed in test media at the start of the test and after 8, 14, 21, and 28 days of exposure. Arithmetic mean measured test concentrations were determined to be <LOQ, 0.00802, 0.0186, 0.0459, 0.113, and 0.273 mg/L. Observations of fish embryos consisted of time to hatching, mortality, eye formation and presence of other developmental abnormalities. After hatching, fish mortality, behaviour, and presence of abnormal appearance was recorded. Finally, body weight and total length of all surviving fish were measured at the end of exposure. Overall appearance of the test solutions were observed at the start and at the end of exposure. The validity criteria of the test were met.

The average time to hatch was significantly increased at test concentrations of 0.0186 to 0.273 mg/L. There were no signs of disturbed eye formation or other any other developmental abnormalities at all test levels. No symptoms of toxicity were observed at embryo phase in all test levels. At the 0.273 mg/L test concentration mortality after hatching was significantly increased. The wet body weight and total length of surviving fish at the end of exposure was significantly decreased at test concentrations of 0.113 and 0.273 mg/L. After hatching, abnormal responses were seen at all test levels, and consisted of complete or partial loss of equilibrium, reduced activity, curved body, extended abdomen, and reduced feeding activity. Reduced activity and reduced feeding activity were assessed to be characteristic symptoms at the 0.273 mg/L test level, and the number of fish displaying these symptoms increased in time. Based on these findings, the 31-d EC10 values were determined to be 0.218 mg/L based on mortality, 0.201 mg/L based on time to hatch, 0.0763 mg/L based on fish total length, and 0.0566 mg/L based on fish weight. All EC10 values are expressed as arithmetic mean measured concentrations. The lowest EC10 of 0.0566 mg/L based on fish weight, is used in the assessment.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

0.057 mg/L