2-hydroxymethyl-9-methyl-6-(1-methylethyl)-1,4-dioxaspiro[4.5]decane

Short-term toxicity to aquatic invertebrates

Description of key information

Under the conditionsof the present study the test substance did not induce acute immobilization of Daphnia magna at or below 32 mg/l after 48 hours of exposure (NOEC) with a 48h EC50 of 63.7 mg/l (95% confidence interval between 56.9 and 75.3 mg/l)

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

63.7 mg/L

Additional information

The key study describes the acute toxicity of the test substance to Daphnia magna based on OECD and EU guidelines. Daphnia were exposed for a maximum of 48 hours to a concentration range of 10 to 100 mg/L. The test was performed in duplicate with 10 daphnia per vessel. Tween 80 was used as an emulsifier (0.1 mL/L).

After 24 hours of exposure the total rate of immobilisation of Daphnia was 75% at 100 mg/l. No immobilisation of daphnia was seen at or below 56 mg/l. The 24h- EC50 was 86.3 mg/l with a 95% confidence interval ranging from 79.7 to 97.8 mg/l (slope 10.5).

 

After 48 hours of exposure the total rate of immobilisation of Daphnia was 90% at 100 mg/l and 35% at 56 mg/l. Still no immobilisation of daphnia was seen at or below 32 mg/l. The 48h- EC50 was 63.7 mg/l with a 95% confidence interval ranging from 56.9 to 75.3 mg/l (slope 6.4).

 

Finally the No Observed Effect Concentration (NOEC) for the test substance with respect to mobility of Daphnia magna was found to be 32 mg/l after 48 hours of exposure.