4-methyl-3-decen-5-ol

Long-term toxicity to aquatic invertebrates

Description of key information

The primary objective of the OECD 211 is to assess the effect of the total number of living offspring produced per animal alive at the end of test. The preferred observational endpoint in long-term studies is the EC10 value because it is derived from the dose response curve. In contrast the NOEC strongly depends on the experiment design (e.g. the concentrations used in the test). Thus the EC10 value for reproduction (number of neonates produced per surviving adult at test termination) has been selected as the key value for PNEC derivation and classification.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

38 µg/L

Additional information

The effects of undecavertol on the survival, growth and reproduction of Daphnia Magna was determined during a 21 day exposure period under static-renewal test conditions.Daphnids were exposed to a geometric series of five test concentrations, a negative control (dilution water) and a solvent control (0.1 mL/L HPLC-grade dimethylformamide). The nominal test concentrations were 9.4, 19, 38, 75 and 150 μg test item /L. Test solutions were renewed every 2-3 days. Mean measured test concentrations were determined from samples of test water collected from each treatment and control group at test initiation, at the beginning and end of the longest renewal cycle each week, and at test termination. The mean measured test concentrations were 5.8, 11, 25, 49 and 99 μg/L, representing 62, 58, 66, 65 and 66% of the nominal concentrations, respectively. The results of the study are based on the mean measured test concentrations.

Negative control and solvent control data for each parameter were compared using an appropriate statistical test. Since no significant differences between the control groups were found for any parameter tested (p > 0.05), the control data were pooled for comparison with the treatment groups.

There were no statistically significant treatment-related effects on survival at concentrations ≤ 49 μg/L. The 21-day EC50 value for adult immobility was 75 μg/L, with the 95% confidence interval of 49 to 99 μg/L. Reproduction, measured as number of neonates produced per surviving first generation daphnid, was the most sensitive biological endpoint measured in this study. Daphnids exposed to Undecavertol at concentrations ≥ 49 μg/L had statistically significant reductions in reproduction in comparison to the pooled controls. Consequently, the NOEC, based on reproduction, was 25 μg/L. The LOEC was 49 μg/L and the MATC (geometric mean of the NOEC and LOEC) was calculated to be 35 μg/L. The 21-day EC10 value for reproduction was 38 μg/L, with the 95% confidence interval of 27 to 54 μg/L, based on number of neonates produced per surviving first generation daphnid at the end of the test and was 49 μg/L, with the 95% confidence interval of 8.9 to 56 μg/L, based on number of neonates produced per adult daphnid at the beginning of the test. The 21-day EC50 value for reproduction was >99 μg/L, based on number of neonates produced per surviving first generation daphnid at the end of the test and was 79 μg/L, with the 95% confidence interval of 69 to 93 μg/L, based on number of neonates produced per adult daphnid at the beginning of the test.