Reaction products of 2-(chloromethyl)oxirane and glycerol

Long-term toxicity to aquatic invertebrates

Description of key information

Aquatic invertebrate reproduction test_Daphnia magna_OECD 211/EU Method C.20: NOEC(21d): 8.3 mg/L, LOEC(21d): 26 mg/L (both: mean measured concentrations), EC50(21d) > 100 mg/L (nominal)

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

8.3 mg/L

Additional information

In the key study, the toxic effects of 1,2,3-Propanetriol, glycidyl ethers towards reproduction and survival of the freshwater invertebrate Daphnia magna were investigated according to OECD Guideline 211 / EU Method C.20 (Liedtke, 2013). The experiment was conducted as semi-static test with renewals every 48 or 72 h. The total exposure duration was 21 days. The water temperature was maintained at 20 - 21 °C and the dark-light-cycle was set at 8 h/16 h with 30 min transition periods. Feeding of the test animals was performed daily each working day with a food mixture containing a suspension of the green algae species Scenedesmus subspicatus and a fish food suspension. The following nominal concentrations of the test substance were tested: 1.0, 3.2, 10, 32 and 100 mg/L. 10 replicates per concentration were prepared. At the start, 10 daphnids per treatment were employed, whereby each animal was kept individually in a glass beaker. Additionally, a control was tested in parallel (test water only). The selection of the test concentrations was based on the results of a range-finding test and on results of a pre-experiment to determine the solubility of the test substance. On Days 0 - 2 and thereafter three times per week, the test replicates were observed for immobility and for the number of living and dead offspring as well as for the presence of aborted eggs. The reproduction rate was calculated as the total number of living offspring produced per parent female surviving until the end of the experiment. The mean reproduction rates at the test concentrations were compared to the control by Williams t-tests. An EC50 value, based on reproduction rate, could not be calculated since none of the responses exceeded 50 %. The value was therefore determined directly from the raw data. High Performance Liquid Chromatography with Mass Spectrometry (HPLC-MS/MS) was the analytical method of choice. The measured test substance concentrations in the freshly prepared test media of the nominal concentrations of 10 and 32 mg/L were between 77 and 97 % of the nominal values at the start of the test medium renewal periods. In the aged test media samples without food, the measured concentrations were between 68 and 82 % of the nominal values. In the aged media samples with food, the measured concentrations were between 69 and 81 % of the nominal values. Similar recoveries were determined in the aged test media samples incubated without food and daphnids. Consequently, the presence of test organisms and organic food had no impact on the test substance dissolved in test water. No remarkable observations on the test media were recorded. All test media were clear solutions throughout the test medium renewal periods. The test substance was not stable during the test medium renewal periods of two and three days. Therefore, all reported biological results are related to the mean measured concentrations. These were calculated as the time-weighted means over the measurements at the start and end of the renewal periods. For the end of the renewal periods, the samples with food were taken into account. In the control and up to and including the highest test concentration, the survival of the test animals at the end of the experiment was at least 90 % or higher. Mortality up to 20 % is regarded as natural and tolerated by the test guideline. Thus, the survival of Daphnia magna over 21 days was not affected by the test item up to and including the highest nominal test concentration of 100 mg/L. The first young offspring released from their parent animals were recorded at the test concentrations of 1.0 - 32 mg/L at observation on Day 9. At the highest test concentration a delay of the first brood was observed (first offspring observed on Day 12 of exposure). Thus, the time of the first brood was not affected by the test substance up to and including the mean measured concentration of 26 mg/L. The mean reproduction rate of the daphnids in the control was 93 +/- 20 living offspring per surviving adult (mean +/- standard deviation). No statistically significant inhibitory effect of the test substance on the mean reproduction rate was determined up to and including the mean measured concentration of 26 mg/L and the highest test concentration, the mean reproduction rates of surviving daphnids was statistically significantly reduced to an average of 69 and 50 living offspring (75 and 54 % compared to the control), respectively. The EC50 was clearly higher than the highest tested concentration of nominal 100 mg/L, because none of the responses exceeded 50 %. As conclusion on the mentioned observations, it can be stated, with the exception of the reduced reproduction rates, no visible abnormalities were observed at the test animals during the experiment. The final results, based on survival and reproduction of the test animals can be reported as followed: NOEC(21d): 8.3 mg/L and LOEC(21d): 26 mg/L as mean measured concentrations. The EC50 value was clearly higher than the highest tested concentration of nominal 100 mg/L, because none of the responses exceeded 50 %.

Supporting information is given as follows. The chronic toxicity to Daphnia of the test substance was predicted by the computer program ECOSAR v1.00 (EPIWIN software) by US-EPA (Chemservice S.A., 2015c).

The computer program ECOSAR v1.00 detected “epoxides, poly” among others as ECOSAR-Class to predict the aquatic chronic toxicity for 1,2,3-Propanetriol, Glycidyl ethers. This class is considered as most suitable class for the substance. A Chronic Values (ChV; 21 d) of 209.8 mg/L for Daphnia was predicted for 1,2,3-Propanetriol, Glycidyl ethers with chlorine included in the main component. Without chlorine, the value differs only to a minimal extend, a ChV of 226.2 mg/L for Daphnia is determined. Both values indicate that there is no toxicity concern.