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

Short-term toxicity to fish

Description of key information

The acute toxicity to fish was examined in a study according to OECD TG 203, and in compliance with GLP (Sinochem, 2013). Groups of 10 zebrafish were exposed to nominal concentrations of 0 (control), 0.40, 0.48, 0.57, 0.67, and 0.80 mg/L for 96 hours under semi-static conditions (24-h renewal of test media). Test substance analysis was performed in fresh medium at the start of the test (fresh medium) and just before the first medium renewal at 24 hours, and at 72 (fresh medium) and at the end of the test. The overall mean measured test concentrations remained well within ±20% of the nominal concentrations for all test media and therefore effect values were expressed as initial measured concentrations. All validity criteria were met.

During the 96 hours exposure period, no toxic symptoms or mortalities were observed in the solvent control group or the lowest concentration test group (arithmetic mean measured concentration of 0.392 mg/L). Toxic symptoms, such as erratic swimming and pigmentation were observed in test groups at measured concentrations from 0.459 mg/L to 0.725 mg/L. Mortalities were observed at measured concentrations of 0.635 mg/L (40% mortality) and 0.725 mg/L (100% mortality). Based on these findings, the 96-h LC50 was determined to be 0.64 mg/L (95% C.L: 0.61 - 0.67 mg./L), based on initial measured concentrations.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

0.64 mg/L

Additional information

In the bioaccumulation study performed with the substance, a toxicity control was performed with Ricefish (Oryzias latipes) in a study according to Japanese Industrial Standards ((JIS) K 0102:2016 section 71). In this semi-static test, the 96 -h EC50 value was determined to be 0.77 mg/L.