Reaction mass of dodecyl acrylate and tridecyl acrylate

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2012-05-16 to 2012-09-14

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

GLP study accroding to guideline. Read across was performed with the read across substance (mixture of laurylacrylate (CAS No.: 2156-97-0) and tetradecylacrylate (CAS No.: 21643-42-5) . Please refer to IUCLID section 13 for read across justification.

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

Version / remarks:

2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

no

Details on sampling:

Concentration control analysis was not performed since the analytical detection limit was above the water solubility of the test substance. However, all reasonable efforts were taken to produce a saturated solution of the test substance in test media, following the guidance in OECD 23. According to OECD 23, for tests with chemicals that cannot be quantified by analytical methods at the concentrations causing effects, the effect concentration can be expressed based on the nominal concentrations.

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Eluate: Due to its poor water solubility, the stability of the test substance in aqueous solution could only be evaluated by preparing a solution as a co-solvent mixture of test media and 1% 1,4-dioxane. The LOQ by this method was 5 mg/L. The test substance was stable in this aqueous solution in a sealed ampoule and at room temperature for up to 96 hours.
- Method: The test substance is poorly water soluble and volatile; therefore a saturated stock solution was prepared using a liquid-liquid saturator technique.
- A volume of 2200 mL test media (and a magnetic stir bar) was added into a glass bottles (2-L) with a bottom side-outlet attached to a valve.
- The test substance container was shaken to ensure homogeneity before use and 275 µL (220 mg based on density) of the test substance was pipetted carefully onto the water surface of each bottle using a syringe.
- The bottle was closed and the solution was stirred on a magnetic plate for approximately 1 day.
- The stirring was slow enough that no vortex formed on the surface, approx. 100 RPM at 20 ± 2°C. After stirring, droplets of undissolved test solution were visible on the surface of the aqueous solution.
- The required volume of saturated test solution was removed from the bottom outlet, leaving remaining solution in contact with the undissolved substance in the bottle. This saturated solution was visibly clear with no visible undissolved test substance. Once removed from the saturation bottle, the saturated solution was handled in sealed vessels as far as possible to avoid atmospheric loss.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Test species / strain: Daphnia magna STRAUS
- Common name: water flea
- Source: The clone of Daphnia magna STRAUS 1820 used was supplied by the Institut National de Recherche Chimique Appliquée, France, in 1978. From this date on this clone was cultured and bred continuously in the Ecotoxicology Laboratory of Experimental Toxicology and Ecology, BASF SE, Ludwigshafen Germany.
- Parental stock: Daphnia brood stock are kept in mass cultures consisting of approx. 20 – 30 individuals for a maximum of 4 weeks. All individuals in the mass culture originate from a single female. After approximately 14 days the adults have produced at least 3 broods and the young can be used in tests. Offspring are removed from the mass cultures at least once daily during the normal work week to ensure that young daphnia are <24-h old (first instar) at test initiation. Only young from healthy cultures without signs of stress are used for testing.
- Age at test initiation: < 24 hours
- Feeding during test: yes
- Food type: During the test daphnids were fed daily a diet of live green algae Desmodesmus subspicatus, cultured in a synthetic medium.
- Amount: The algae were separated from their culture medium by centrifugation, resuspended in daphnid's medium (M4) corresponding to concentrations of 2000 mg, 1460 and 1870 mg TOC*/L (respectively) in the algal concentrates used. The daphnids were fed a defined volume (= 137 µL) of the concentrate.The algae were stored in a refrigerator (dark, about 4-8°C) for maximum 21 days. By adding the algal concentrate the test solution was slightly diluted. During a 24 hour test interval with 1 feeding, 0.137 mL each, a total of 0.137 mL are added to 50 mL test volume resulting in a maximal dilution of 0.27%.
- Frequency: daily

ACCLIMATION
- Acclimation period: The Daphnia are cultured under the identical conditions as the test including test media (Elendt M4), water quality, temperature (20 ±1°C), and diet.
- Acclimation conditions: yes

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

21 d

Hardness:

2.20 – 3.20 mmol/L

Test temperature:

20.0 °C - 20.5 °C

pH:

7.5 - 8.5

Dissolved oxygen:

Must remain = 3mg/L during the test. To assure optimal dissolved oxygen levels, the M4 medium is aerated for approximately 24 hours prior to use.

Nominal and measured concentrations:

Nominal concentration: 100 mg/L
No concentrations were measured.

Details on test conditions:

TEST SYSTEM
- Test groups: 0 (control), 100 mg/L as nominal (loading) concentrations
- Replicates / test group: 10 replicates (1 parent animal each)
- Reason for the selection of the test concentrations: In a preliminary test (experimental conduct in accordance with GLP but without a GLP status), after 15 days exposure to the test substance, no significant effect on reproduction was observed at 10 mg/L.
- Test vessel: glass flask
- Type: closed
- Material, size, headspace, fill volume: nominal volume 50 mL
- Aeration: none
- No. of organisms per vessel: 1
- No. of vessels per concentration (replicates): 10
- No. of vessels per control (replicates): 10
- Biomass loading rate: 0.02 animals/mL

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: A synthetic fresh water (Elendt M4) is used as media for culture and test purposes. For the composition of this M4 medium see OECD 211 (2008). The general properties of this medium are as follows:
- Total hardness: 2.20 – 3.20 mmol/L
- Acid capacity up to pH 4.3: 0.80 – 1.00 mmol/L
- Molar ratio Ca:Mg: about 4 : 1
- pH value: 7.5 – 8.5
- Conductivity: 550 - 650 µS/cm
- Total organic carbon: < 2 mg/L
- Dissolved oxygen: Must remain = 3mg/L during the test. To assure optimal dissolved oxygen levels, the M4 medium is aerated for approximately 24 hours prior to use.
- Culture medium different from test medium: no

OTHER TEST CONDITIONS
- Photoperiod: 16:8 light/darkness
- Light intensity: About 638 - 689 lux at a wave length of 400 - 750 nm

EFFECT PARAMETERS MEASURED: mortality, reproduction and other sublethal effects. Additional endpoints (i.e. growth, immobile young, time to first brood, or aborted eggs) were checked.

VEHICLE CONTROL PERFORMED: yes
Due to its poor water solubility, the stability of the test substance in aqueous solution could only be evaluated by preparing a solution as a co-solvent mixture of test media and 1% 1,4-dioxane. The LOQ by this method was 5 mg/L. The test substance was stable in this aqueous solution in a sealed ampoule and at room temperature for up to 96 hours

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Duration:

21 d

Dose descriptor:

EC10

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

21 d

Dose descriptor:

EC10

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

The test substance had no observable chronic effect on Daphnia magna up to its saturation limit in test media and under test conditions.
The results in this study are consistent with all validity criteria and the test is valid according to the guidelines of this study. No deviations from test guidelines or other incidents occurred during the course of the reported test which may have influenced the results. No effect on mortality (21 d EC0 = 100 mg/L) and reproduction or any adverse effects on additional endpoints (i.e. growth, immobile young, time to first brood, or aborted eggs) were observed in any of the test treatments.
Summarized effect parameters for the main endpoints, reproduction (living young) and % mortality of the parent animals after 21 days based on nominal loading concentrations. The data were not sufficient to calculate ECx values for reproduction or growth, since the study is designed as a limit test.
Therefore the results were: NOEC >= 100 mg/L, LOEC>100 mg/L, EC10>100 mg/L and EC50 > 100 mg/L.

Results with reference substance (positive control):

In order to verify that the Daphnia magna culture is responding normally to toxic stress, tests with a reference substance, potassium dichromate (K2Cr2O7), are conducted monthly.
Reference substance tests are conducted according to OECD 202 guidelines and in accordance with GLP, but without a GLP status.
The EC50(24h) of the reference substance potassium dichromate was 0.68 mg/L (experiment date: 15 May 2012, project number: 50E0063/043039).
These results are within the range of 0.6 – 2.1 mg/L (ISO 6341) and indicate that the culture of Daphnia magna used in this study were responding normally to toxic stress.

Reported statistics and error estimates:

Student´s t-test was used to evaluate any differences in reproduction and growth between the test concentration and control.
Wilcoxon’s test (one sided analysis) was used to evaluate any differences in the time to the first brood. The results of the statistical analyses were used to aid in the determination of the NOEC and LOEC. However, scientific judgment was used to determine if statistical differences were biologically meaningful. In this limit test with one test concentration, the NOEC was defined as greater than or equal to the saturation concentration under test conditions when no significant treatment-related effects on survival, reproduction or growth are observed.
The LOEC was defined as greater than the NOEC when no significant treatment-related effects on survival, reproduction or growth are observed. Effect concentrations (ECx) could not be calculated since there were no effects at the tested concentrations. ECx values, where reported, are estimates based on best professional judgment.

Reference 2

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

other information

Reason / purpose for cross-reference:

read-across source

Description of key information

A study on the long-term effects on daphnids according to the OECD Test Guideline 211 was performed with an analogue (Lauryl Acrylate C12-C14, CAS Number 84238-60-8).

The test item had no observable effects on Daphnia magna up to its saturation limit in the test medium. The 21-day NOEC is equal to or greater than the highest nominal concentration tested (100 mg/L, saturated stock solution prepared with a liquid-liquid saturation technique).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L