Dodecanoic acid, 2,2-dimethyl-3-oxopropyl ester

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2004-11-18 to 2005-08-12

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

adopted 1992

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Version / remarks:

adopted 1992

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Sampling preparation:
Aqueous samples (10.0 mL) were membrane filtrated (Nylon, 0.45 μm). The filtrate was acidified with 2M-HCl to pH 2 – 3. 10.0 mL of the filtrate were given on the top of a column with 5.0 g Extrelute. After 30 minutes, elution was slowly performed with ethyl acetate (50 mL, 30 minutes), the eluate wasrotated down to dryness and 500 μL ISTD-solution were added. At last, 400 μL of the solution were mixed with 50 resp. 100 μL SIL -Mix in vials, and silylation was performed at 80 °C for 60 minutes.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
1. Experiment:
- Method: As the test item is poorly water soluble, the “water-accommodated fraction” was tested. This was done by weighing the nominal load 100 mg/L, adding the corresponding amount of dilution water and shaking vigorously for 24 hours. As it was not possible to filtrate or centrifugate the resulting solution the test was performed with the unfiltrated emulsion.
- Differential loading: 100 mg/L nominal load
- Controls: one vessel
2. Experiment:
- Method: A stock solution containing 10 g/L in acetone was prepared. On each day of the test, the treatments 0.1 and 1 mg/L were prepared by spiking the corresponding amount of dilution water with this stock solution
- Differential loading: 0.1 / 1 mg/L
- Controls: one vessel
3. Experiment:
- Method: A stock solution containing 10 g/L in acetone was prepared. On each day of the test, the treatment 1 mg/L was prepared by spiking the corresponding amount of dilution water with this stock solution.
- Differential loading: 0.1 / 1 mg/L
- Controls: one vessel

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: Danio rerio
- Source: Weiler´s Pet´s best, Turmstr. 6, 67433 Neustadt
- Length at study initiation (length definition, mean, range and SD): 2 ± 1 cm
- Amount: totalling to about 1-2% of body weight per day
- Frequency: three times a day

ACCLIMATION
- Acclimation period: 14 days
- Acclimation conditions: same as test conditions
- Health during acclimation: no mortality observed

Test type:

other: 1.Experiment: static; 2 and 3. Experiment: semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Test temperature:

1. 22.8 – 23.0 °C
2. 22.0 – 22.4 °C
3. 22.0 – 23.0 °C

pH:

1. 7.9 to 8.2
2. 8.0 to 8.2
3. 7.9 to 8.1

Dissolved oxygen:

above 8.3 mg/L

Nominal and measured concentrations:

100, 1, 0.1 mg/L (nominal)

Details on test conditions:

TEST SYSTEM
- Test vessel: glass aquaria, maximal volume 10 L
- Renewal rate of test solution (frequency/flow rate):
- No. of organisms per vessel:
1. Experiment:
7 L test solution and 7 fish
2. Experiment:
3 L test solution and 3 fish
3. Experiment:
7 L test solution and 7 fish
- No. of vessels per concentration: one vessel
- No. of vessels per control: one vessel
- No. of vessels per vehicle control: one vessel
- Biomass loading rate: 1 fish/L

OTHER TEST CONDITIONS
- Adjustment of pH: none
- Photoperiod: 12/12 hours using neon tubes

Reference substance (positive control):

no

Duration:

24 h

Dose descriptor:

NOEC

Effect conc.:

>= 1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

> 1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

>= 1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

> 1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

>= 1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

72 h

Dose descriptor:

LC50

Effect conc.:

> 1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

>= 1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

1. Experiment:
The fish were found dead after 48 hours. During the shaking period for the preparation of the WAF, an emulsion was produced. This emulsion couldn’t be filtrated or centrifuged. The unsolved part of the test item rose to the surface. This effect probably caused the mortality. Therefore the experiment was repeated, but the test solution was prepared by spiking with an acetone stock solution.
2. Experiment:
None of the fish died or showed any signs of morbidity during the test. Based on these results, a further experiment with analytical determination was performed. In order to ensure testing at the maximal water solubility, the treatment 1 mg/L was chosen.
3. Experiment:
A thin oily film on the surface could be observed, but none of the fish died or showed any signs of abnormality during the test. This experiment was used to determine the biological results.

Sublethal observations / clinical signs:

At the start of the test, at every medium renewal and four hours after each renewal, the content of the test item in each test solution was determined using GC. The measured concentrations of the fresh test solutions (at the start of the test and at each medium renewal after every 24 hours) were between 36 and 53 % of the nominal concentration. Sample preparation and clean-up requires about one hour. During this time, the test item already undergoes hydrolysis which probably caused the lower recoveries. The measured concentrations 4 hours after each medium renewal were between 7and 37 % of the nominal concentration. The test item is not stable in water (as has been demonstrated in the respective study “determination of water solubility”). Due to the rapid degradation, referring to determined values is not meaningful and only the nominal values were used.

Validity criteria fulfilled:

yes

Conclusions:

The 96 h LC50 was determined at greater than 1 mg/L and the 96 h NOEC was 1 mg/L.

Executive summary:

The study was performed in order to evaluate the toxic potential of the product 2,2-Dimethyl-3-lauroyloxy-propanal the toxic potential of test item towards freshwater fish, using the species Danio rerio. Three experiments were performed. As the test item is poorly water soluble, the “water-accommodated fraction” was tested in the first experiment. This was done by weighing the nominal load 100 mg/L, adding the corresponding amount of dilution water and shaking vigorously for 24 hours. As it was not possible to filtrate or centrifuge the resulting emulsion, the test was performed with the unfiltered emulsion. Seven fish were exposed to the test item for 96 hours in a static test. After 48 hours, 100 % mortality was observed in the treatment, probably caused by the undissolved test item. In the control, none of the fish showed signs of morbidity at the end of the test. The pH and the oxygen values were normal. Experiments two and three were performed under semi-static conditions with medium renewal after 24 hours. For the second experiment a stock solution in acetone was prepared. The treatments 0.1 mg/L and 1 mg/L were prepared by spiking the corresponding amount of dilution water with this stock solution. The treatment concentration of 1 mg/L was above maximal water solubility of 0.227 mg/L. Three fish were exposed to the test item for 96 hours. No mortality was observed in both treatment groups and the control. Based on these experiments, the third experiment was performed as a limit-test under semistatic conditions, using a treatment concentration of 1 mg/L with an acetone-spiked test solution. Seven fish were exposed to the test item for 96 hours in a static test. None of the fish died or showed signs of toxicity during the test. The pH and the oxygen values were normal. The 96 h LC50 was determined at greater than 1 mg/L and the 96 h NOEC was 1 mg/L. These data were already submitted in a NONS dossier under Directive 92/32/EEC (notification number 05-04-1922-00 from 2005-10-25) and considered valid and uncritical from the German Competent Authority (BAUA).

Description of key information

Aldehyde L was assessed in a short-term toxicity to fish study according to EU-method C.1 and OECD guideline 203. Fish were exposed to static and semi-static conditions at a nominal concentration of 100, 1 and 0.1 mg/L. The 96 h LC50 was determined at greater than 1 mg/L and the 96 h NOEC was 1 mg/L.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC50

Effect concentration:

> 1 mg/L

Additional information

The study was performed in order to evaluate the toxic potential of the product 2,2-Dimethyl-3-lauroyloxy-propanal the toxic potential of test item towards freshwater fish, using the species Danio rerio. Three experiments were performed. As the test item is poorly water soluble, the “water-accommodated fraction” was tested in the first experiment. This was done by weighing the nominal load 100 mg/L, adding the corresponding amount of dilution water and shaking vigorously for 24 hours. As it was not possible to filtrate or centrifuge the resulting emulsion, the test was performed with the unfiltered emulsion. Seven fish were exposed to the test item for 96 hours in a static test. After 48 hours, 100 % mortality was observed in the treatment, probably caused by the undissolved test item. In the control, none of the fish showed signs of morbidity at the end of the test. The pH and the oxygen values were normal. Experiments two and three were performed under semi-static conditions with medium renewal after 24 hours. For the second experiment a stock solution in acetone was prepared. The treatments 0.1 mg/L and 1 mg/L were prepared by spiking the corresponding amount of dilution water with this stock solution. The treatment concentration of 1 mg/L was above maximal water solubility of 0.227 mg/L. Three fish were exposed to the test item for 96 hours. No mortality was observed in both treatment groups and the control. Based on these experiments, the third experiment was performed as a limit-test under semistatic conditions, using a treatment concentration of 1 mg/L with an acetone-spiked test solution. Seven fish were exposed to the test item for 96 hours in a static test. None of the fish died or showed signs of toxicity during the test. The pH and the oxygen values were normal. The 96 h LC50 was determined at greater than 1 mg/L and the 96 h NOEC was 1 mg/L. These data were already submitted in a NONS dossier under Directive 92/32/EEC (notification number 05-04-1922-00 from 2005-10-25) and considered valid and uncritical from the German Competent Authority (BAUA).