Methoxycarbonyloxycyclooct-4-ene

Toxicity to aquatic algae and cyanobacteria

Description of key information

The toxicity of the substance to aquatic algae was examined in a study according to OECD TG 201, and in compliance with GLP (Huntingdon, 2005). In this study, cultures of freshwater green algae (P. subcapitata) were exposed to nominal test concentrations of 0 (control), 0.68, 1.49, 3.29, 7.23, 15.9 and 35 mg/L for 72 hours. Test substance analysis was performed and at the start of the test measured concentrations ranged from 90 to 98% of nominal except for the 0.68 mg/L test concentration in which the measured level was slightly lower (74% on nominal). After 72 hours, the measured levels at all concentrations had decreased, ranging from 37 to 69% of nominal (ca. 47 - 72%). Therefore, the geometric mean measured concentrations were calculated, and effect values expressed as such. Geomean measured concentrations were <0.06 (control), 0.353, 1.02, 2.21, 5.48, 10.6 and 28.5 mg/L. Cell densities were recorded at 24, 48 and 72 h after the start of the test, and the effect on algal growth rate determined. Based on the findings in the test, the 72h-ErC50, ErC10, and NOErC were determined to be 8.18 (95% C.I. 7.18-9.17 mg/L), 3.72 (95% C.I. 2.35-4.67 mg/L), and 1.02 mg/L, respectively based on geometric mean measured concentrations.

Key value for chemical safety assessment

EC50 for freshwater algae:

8.18 mg/L

EC10 or NOEC for freshwater algae:

3.7 mg/L