Reaction products of 1,4-cyclohexanedimethanol with propylene oxide and ammonia

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:

2012-03-06 - 2012-04-22

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:

yes

Remarks:

Temperature, oxygen and pH ranges outside of recommended parameters

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Water samples were taken from the control and each test group (replicates R1-R4 pooled) at 0 and 48 h for quantitative analysis.
- Duplicate samples were taken.
- All samples were stored at approximately -20 °C prior to analysis.

Vehicle:

no

Details on test solutions:

- During the range finding test (1.0, 10 and 100 mg/L loading rates), test solutions were stirred for 23 h after addition of test item (preparation of WAFs, Water Accomodated Fractions). In the 100 mg/L loading rate a significant amount of dispersed test item was observed and therefore the test solutions were filtered over a glass wool plug. However, analytical measurement of the test concentrations indicated that the test item was soluble and therefore the test item was dissolved directly in the test medium for the purpose of the definitve test.
- The 100 mg/L test concentrations was prepared directly by adding 500 mg of the test substance 5 L of test medium.
- The other test concentrations for the definitve test were prepared by dilution (not sequential) of the 100 mg/L solution.
- Each prepared concentration was inverted several times to ensure adequate mixing and homogeneity.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Strain: 1st instar Daphnia magna
- Source: in-house laboratory culture
- Age at study initiation (mean and range, SD): < 24 h
- Method of breeding: parthenogenesis
- Feeding during test: no

ACCLIMATION
- Acclimation period: no specific acclimation period
- Acclimation conditions (same as test or not): same as test
- Feeding during culturing: daily with a mixture of algal suspension (Desmodesmus subspicatus) and Tetramin flake food suspension

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

None

Hardness:

250 mg CaCO3/L

Test temperature:

19-22 degrees C (> 1°C deviation during test, however, this was not considered to affect integrity of test results, moreover, the deviation in individual test vessels was never > 1°C)

pH:

6-9 (pH of 18 and 100 mg/L test solution at 0 h was above the recommended range of 6-9, however, this was not considered to affect the integrity of the test results given that immobilisation was also observed at the test concentration of 10 mg/L which showed a pH within the recommended range)

Dissolved oxygen:

ASV > 100% (most likely due to presence of microscopic air bubbles in the test media, this was not considered to affect integrity of test results)

Salinity:

N/A

Nominal and measured concentrations:

Nominal concentrations: control, 1.0, 1.8, 3.2, 5.6, 10, 18, 32, 56 and 100 mg/L
Measured concentrations ranged from 84-107% of nominal

Details on test conditions:

TEST SYSTEM
- Test vessel: jars
- Type (delete if not applicable): covered
- Material, size, headspace, fill volume: glass, 250 mL, 200 mL fill volume
- Aeration: none
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: deionised reverse osmosis water
- Test medium: reconstituted water - Elendt M7 medium
- Culture medium different from test medium: no
- Intervals of water quality measurement: batch
- During the test, water temperature and light intensity were recorded daily. Dissolved oxygen concentrations and pH were recorded at the start and termination of the test.

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 hours light and 8 hours darkness with 20 minute dawn and dusk transition periods
- Light intensity: 632-663 lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): immobility, 24 and 48 h

TEST CONCENTRATIONS
- Spacing factor for test concentrations:~2
- Range finding study: yes
- Test concentrations during range finding study: 1.0, 10, and 100 mg/L
- Results used to determine the conditions for the definitive study: yes

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

7.5 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% CI = 5.6-10 mg/L

Details on results:

- Mortality of control: none
- Other adverse effects control: none
- Abnormal responses: none
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: none
- Effect concentrations exceeding solubility of substance in test medium: none

Results with reference substance (positive control):

The results from the positive control with potassium dichromate were within the normal range for this reference item.
48-h EC50 = 1.1 mg/L (95% CI = 1.0-1.3 mg/L)

Reported statistics and error estimates:

48-EC50 value and 95% CI calculated using the geometric mean method (no partial mortality).

The Lowest Observed Effect Concentration (LOEC) was considered to be 10 mg/L. The No Observed Effect Concentration (NOEC) was 5.6 mg/L.

Validity criteria fulfilled:

yes

Conclusions:

The 48-h EC50 of the test substance for Daphnia magna was 7.5 mg/L with 95% confidence limits of 5.6 - 10 mg/L. Analytical verification of test substance concentrations showed measured concentrations to be close to nominal. The results of this test can therefore be considered reliable.

Description of key information

In this study, the acute toxicity of the test substance to Daphnia magna was investigated in a 48-h static study with concentrations between 0 and 100mg/L, resulting in a 48-h EC50 of 7.5 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

7.5 mg/L

Additional information

The acute study of Goodband and Mullee (2012) was used as a key study for PNEC derivation. The 48-h test with Daphnia magna was conducted according to OECD guideline 202. The test concentrations were were 1, 1.8, 3.2, 5.6, 10, 18, 32, 56, 100 mg/L and were within 84 -107% of the nominal range. A 48-h EC50 of 7.5 mg/L for Daphnia magna was obtained in this study. This indicates that the test substance is toxic to aquatic invertebrates.