Oligomerisation products of 2,2'-[(1-methylethylidene)bis(4,1-phenyleneoxymethylene)]bisoxirane with acrylic acid and lauric 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:

July 30, 2012 to december 7, 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: This study has been performed according to OECD and/or EC guidelines and according to GLP principles

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

Qualifier:

according to guideline

Guideline:

other: Guidance document on aquatic toxicity testing of difficult substances and mixtures, OECD series on testing and assessment number 23, December 14, 2000

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

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 appended Analytical Report
Frequency: at t=0 h and t=48 h
Volume: 2 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.

Additionally, reserve samples of 2 ml were taken for possible analysis. If not used, these samples are stored in a freezer for a maximum of three months after delivery of the draft report, pending on the decision of the sponsor for additional analysis.

Vehicle:

no

Details on test solutions:

The batch of RD04/201 tested was a clear colourless viscous liquid and was not completely soluble in test medium at the loading rates prepared. Weighing of test substance and preparation of test concentrations was performed under dimmed light.
All test solutions were prepared separately and started with loading rates ranging from 1.0 to 100 mg/l in test medium with a temperature of 60°C. Two days of magnetic stirring at room temperature was applied to reach maximum solubility of the test substance in the test medium. The resulting aqueous mixtures were left to stabilize for 2-2.5 hours where after the, generally, clear and colourless WAFs were siphoned off and used for testing. Note that the WAFs prepared at 56 and 100 mg/l for final test 2 were observed to be increasingly hazy.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna (Crustacea, Cladocera) (Straus, 1820)
- Source: In-house laboratory culture with a known history.
- Age at study initiation: < 24 hours
- Method of breeding: With newborn daphnids, i.e. less than 3 days old, by placing about 250 of them into 10 litres of medium in an all-glass culture vessel.
- Feeding during test: No

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

180 mg/l expressed as CaCO3

Test temperature:

Between 18.7 and 19.4 °C

pH:

between 7.8 and 8.0

Dissolved oxygen:

between 8.1 and 9.0 mg/l O2

Nominal and measured concentrations:

Nominal concentrations: WAFs prepared at loading rates of 1.0, 2.2, 4.6, 10, 22, 46 and 100 mg/l
Measured concentrations: Actual test concentrations were based on the major component of the test substance. Analysis of the samples taken at the start of the test showed measured concentrations of 1.1, 2.2, 3.4, 3.0, 2.8, 3.1 and 44 mg/l in the WAFs prepared at 1.0, 2.2, 4.6, 10, 22, 46 and 100 mg/l. These concentrations remained stable during the test period (87-91% of initial) except for the highest concentration that decreased to 64% of initial at the end of the test. For the determination of the effect parameters, average exposure concentrations were calculated and used in ascending order, i.e. 1.1, 2.1, 2.7, 2.9, 3.2 and 35 mg/l.

Details on test conditions:

Type (delete if not applicable): open
- Material, size, headspace, fill volume: glass, 100 ml, normal headspace, 80 ml
- Aeration: no
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4 for the highest concentration and 2 for the lower concentrations
- No. of vessels per control (replicates): 4
TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Adjusted ISO medium: the following chemicals (analytical grade) are dissolved in tap water purified by Reverse Osmosis (RO-water, GEON Waterbehandeling, Berkel-Enschot, The Netherlands):
Macro salts:
CaCl2.2H2O : 211.5 mg/l
MgSO4.7H2O: 88.8 mg/l
NaHCO3 : 46.7 mg/l
KCl : 4.2 mg/l
The hardness: 180 mg/l expressed as CaCO3 and the pH: 7.7 ± 0.3 after aeration.
- Culture medium different from test medium: yes, for culturing M7 medium is used
OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 hours photoperiod daily
EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : EC50 t=24 and 48 h
TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2.2
- Test concentrations: control and WAFs prepared at loading rates of 1.0, 2.2, 4.6, 10, 22, 46 and 100 mg/l

Reference substance (positive control):

yes

Remarks:

potassium dichromate (K2Cr2O7,)

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

2.9 mg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% confidence interval 2.6 - 3.4 mg/l

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

1.7 mg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% confidence interval 1.4 - 1.9 mg/l

Details on results:

Behavioural abnormalities: no
- Immobility of control: no immobility was observed.
- Other adverse effects control: no

Results with reference substance (positive control):

The actual responses in this reference test with K2Cr2O7 were in the lower range 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 in agreement with the historical data collected at WIL Research Europe.

The 24h-EC50 was 0.66 mg/l with a 95% confidence interval between 0.59 and 0.77 mg/l.

The 48h-EC50 was 0.38 mg/l with a 95% confidence interval between 0.34 and 0.45 mg/l.

Reported statistics and error estimates:

The EC50-value was calculated at 24 and 48 hours of exposure from the probits of the percentages of affected daphnids and the logarithms of the corresponding test substance concentrations using the maximum likelihood estimation method (Finney, D.J., 1971: Probit analysis, Cambridge University Press, Cambridge, U.K., 3rd edition).

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of the present study RD04/201 induced acute immobilisation of Daphnia magna at average exposure concentrations of 1.1 mg/L and higher.

The 48h-EC50 was 1.7 mg/L (95% confidence interval between 1.4 and 1.9 mg/L).

Executive summary:

A study was conducted to determine the acute toxicity to daphnia according to OECD Guideline 202, EU method C.2 and ISO Method 6341, under GLP principles. Daphnia manga was tested under static conditions for 48 h. Owing to the poor water solubility of the test substance, all test solutions were prepared as water accomodated fractions (WAFs). The test solutions were prepared with loading rates ranging from 1.0 to 100 mg/L in test medium assisted by magnetic stirring and left to stabilize and used for testing. Twenty daphnids per concentration (four replicates, five daphnids per concentration) were exposed to WAFs prepared at loading rates of 0, 1.0, 2.2, 4.6, 10, 22, 46 and 100 mg/L. The total test period was 48 hours and samples for analytical confirmation of actual exposure concentrations were taken at the start and the end of the test. Actual test concentrations were based on the major components of the test substance. These concentrations remained stable during the test period (87-91% of initial) except for the highest concentration that decreased to 64% of initial at the end of the test. For the determination of the effect parameters average exposure concentrations were calculated. The study met the acceptability criteria prescribed by the protocol and was considered valid. The test substance induced acute immobilisation of Daphnia magna at average exposure concentrations of 1.1 mg/l and higher. Under the study conditions, the 48 h EC50 of the test substance was determined to be 1.7 mg/L (Bouwman, 2013).

Description of key information

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

1.7 mg/L

Additional information

A study was conducted to determine the acute toxicity to daphnia according to OECD Guideline 202, EU method C.2 and ISO Method 6341, under GLP principles. Daphnia manga was tested under static conditions for 48 h. Owing to the poor water solubility of the test substance, all test solutions were prepared as water accomodated fractions (WAFs). The test solutions were prepared with loading rates ranging from 1.0 to 100 mg/L in test medium assisted by magnetic stirring and left to stabilize and used for testing. Twenty daphnids per concentration (four replicates, five daphnids per concentration) were exposed to WAFs prepared at loading rates of 0, 1.0, 2.2, 4.6, 10, 22, 46 and 100 mg/L. The total test period was 48 hours and samples for analytical confirmation of actual exposure concentrations were taken at the start and the end of the test. Actual test concentrations were based on the major components of the test substance. These concentrations remained stable during the test period (87-91% of initial) except for the highest concentration that decreased to 64% of initial at the end of the test. For the determination of the effect parameters average exposure concentrations were calculated. The study met the acceptability criteria prescribed by the protocol and was considered valid. The test substance induced acute immobilisation of Daphnia magna at average exposure concentrations of 1.1 mg/l and higher. Under the study conditions, the 48 h EC50 of the test substance was determined to be 1.7 mg/L (Bouwman, 2013).