Oligomerisation products of 2,2'-[(1-methylethylidene)bis(4,1-phenyleneoxymethylene)]bisoxirane with acrylic acid and fatty acids, C18-unsatd., dimers and nonanoic acid

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From January 30, 2012 to February 01, 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

Qualifier:

according to guideline

Guideline:

ISO 6341 (Water quality - Determination of the Inhibition of the Mobility of Daphnia magna Straus (Cladocera, Crustacea))

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

The test substance was a clear green to brown highly viscous liquid with unknown purity.

Analytical monitoring:

yes

Details on sampling:

Determination of the concentrations, Oudhoff, 2012.
Samples for possible analysis were taken from all test concentrations and the control according to the schedule below. The method of analysis is described in the Analytical Report (APPENDIX 2) (Oudhoff, 2012).
Frequency: at t=0 h and t=48 h. Volume: 3 mL from the approximate centre of the test vessels. Storage: samples were stored in a freezer until analysis. At the end of the exposure period, the replicates were pooled at each concentration before sampling.

Vehicle:

yes

Remarks:

M7, as prescribed by Dr. Elendt-Schneider (Elendt, B.-P., 1990: Selenium deficiency in Crustacea. An ultrastructural approach to antennal damage in Daphnia magna Straus. Protoplasma 154, 25-33).

Details on test solutions:

A combined limit/range-finding test was performed. Preparation of test solutions started with individually prepared loading rates of 1.0, 10 and 100 mg/L applying a 1-hour period of magnetic stirring followed by a 0.5-hour settlement period. The clear and colourless Water Accommodated Fractions (WAFs) were subsequently siphoned and used as test solutions.

Test organisms (species):

Daphnia magna

Details on test organisms:

Species: Daphnia magna (Crustacea, Cladocera) (Straus, 1820), at least third generation, obtained by acyclical parthenogenesis under specified breeding conditions. Source: in-house laboratory culture with a known history. Reason for selection: this system has been selected as an internationally accepted invertebrate species. Validity of batch: daphnids originated from a healthy stock, 2nd to 5th brood, showing no signs of stress such as mortality >20%, presence of males, ephippia or discoloured animals and there was no delay in the production of the first brood.
Characteristics: for the test selection of young daphnids with an age of < 24 hours, from parental daphnids of more than two weeks old. Start of each batch: with newborn daphnids, i.e. less than 3 days old, by placing about 250 of them into 5 litres of medium in an all-glass culture vessel. Maximum age of the cultures: 4 weeks. Renewal of the cultures: after 7 days of cultivation half of the medium twice a week. Feeding: daily, a suspension of fresh water algae.

Test type:

static

Water media type:

other: M7 = adjusted ISO medium

Limit test:

yes

Total exposure duration:

48 h

Post exposure observation period:

no

Hardness:

180 mg/l expressed as CaCO3

Test temperature:

18-22°C

pH:

7.7 +/- 0.3

Dissolved oxygen:

The oxygen concentration at the end of the test was ≥ 3 mg/L in control and test vessels.

Conductivity:

-

Nominal and measured concentrations:

measured concentrations

Details on test conditions:

Twenty daphnids per group (5 per vessel, 4 vessels) were exposed to a control and a WAF prepared at a loading rate of 100 mg/L in a limit test. In addition, ten daphnids per group (5 per vessel, 2 vessels) were exposed to WAFs prepared at 1.0 and 10 mg/L. The total exposure period was 48 hours and samples for analytical confirmation of the exposure concentrations were taken at the start and at the end of the test.

Reference substance (positive control):

yes

Remarks:

potassium dichromate (K2Cr2O7)

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 0.16 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mobility

Remarks on result:

other: EC50 > maximum soluble concentration

Remarks:

This is equivalent to nominal concentration of 100 mg/L

Details on results:

Analysis of the samples taken at the start of the test showed measured concentrations of 0.0022, 0.02 and 0.16 mg/L in WAFs prepared at loading rates of 1.0, 10 and 100 mg/l, respectively. At the end of the test there was no response observed in the lowest WAF, whereas at the two remaining WAFs the measured concentrations remained stable (86-94% of initial).

Results with reference substance (positive control):

The 24h-EC50 was 0.53 mg/l with a 95% confidence interval between 0.47 and 0.62 mg/L
The 48h-EC50 was 0.28 mg/l with a 95% confidence interval between 0.26 and 0.32 mg/L

Reported statistics and error estimates:

The actual responses in this reference test with K2Cr2O7 were just outside (below) the ranges of the expected historical responses at the different concentrations, i.e. a 48h-EC50 between 0.3 and 1.0 mg/L. Hence, the sensitivity of this batch of D. magna was slightly higher when compared to the historical data collected at NOTOX.

Analysis of the samples taken at the start of the test showed measured concentrations of 0.0022, 0.02 and 0.16 mg/L in WAFs prepared at loading rates of 1.0, 10 and 100 mg/L, respectively. Note that at the two lowest WAFs the obtained values were only indicative as they were obtained by extrapolation of the calibration curve. At the end of the test there was no response observed in the lowest WAF, whereas at the two remaining WAFs the measured concentrations remained stable (86-94% of initial).

As the effect parameters were based solely on the observations made in the highest WAF, they were expressed in terms of initially measured concentrations.

Observations:

No biologically significant immobilisation was observed in the control and the two highest concentrations. Note that the guideline allows 10% immobilisation in the control treatment. In the lowest concentration tested 60% of the daphnids were immobilized at the end of the test. As no significant effects were observed in the two higher concentrations it was assumed that the observed effect was not test substance related. This was also confirmed with the measured concentrations.

Validity criteria fulfilled:

yes

Conclusions:

Under the study conditions, the 48h EC50 (Daphnia magna) of the test substance was determined to be: > 0.16 mg/L. (Actually, no EC50 could be calculated because the EC50 was greater that the maximum soluble concentration).

Executive summary:

A study was conducted to determine the short-term toxicity of the test substance to aquatic invertebrates according to OECD Guideline 202, EU Method C.2 and ISO 6341 15. Daphnia magna were exposed for 48 h to WAFs prepared at loading rates of 0 (control), 1.0, 10 and 100 mg/L under static conditions. Mobility of the Daphnia was evaluated at 0 and 48 h and samples for analytical dose verification were taken from all groups at test start and end. Analysis of the samples taken at test start showed measured concentrations of 0.0022, 0.02 and 0.16 mg/L in the WAFS at 1.0, 10 and 100 mg/L, respectively. At the end of the test there was no response observed in the lowest WAF, whereas at the two remaining WAFs the measured concentrations remained stable (86-94% of initial). No biologically significant immobilisation was observed in the control and the two highest concentrations. In the lowest concentration tested, 60% of the daphnids were immobilized at the end of the test. As no significant effects were observed in the two higher concentrations, it was assumed that the observed effect was not treatment-related. This was also confirmed with the measured concentrations. Under the study conditions, the 48h EC50 for Daphnia magna was determined to be > 0.16 mg/L (Tobor-Kaplon, 2012).

Description of key information

The 48h EC50 for Daphnia magna was determined to be > 0.16 mg/L (measured; corresponding to nominal concentration of 100 mg/L).

Additional information

A study was conducted to determine the short-term toxicity of the test substance to aquatic invertebrates according to OECD Guideline 202, EU Method C.2 and ISO 6341 15. Daphnia magna were exposed for 48 h to WAFs prepared at loading rates of 0 (control), 1.0, 10 and 100 mg/L under static conditions. Mobility of the Daphnia was evaluated at 0 and 48 h and samples for analytical dose verification were taken from all groups at test start and end. Analysis of the samples taken at test start showed measured concentrations of 0.0022, 0.02 and 0.16 mg/L in the WAFS at 1.0, 10 and 100 mg/L, respectively. At the end of the test there was no response observed in the lowest WAF, whereas at the two remaining WAFs the measured concentrations remained stable (86-94% of initial). No biologically significant immobilisation was observed in the control and the two highest concentrations. In the lowest concentration tested, 60% of the daphnids were immobilized at the end of the test. As no significant effects were observed in the two higher concentrations, it was assumed that the observed effect was not treatment-related. This was also confirmed with the measured concentrations. Under the study conditions, the 48h EC50 for Daphnia magna was determined to be > 0.16 mg/L (Tobor-Kaplon, 2012). This corresponds to a nominal concentration of 100 mg/L.