2-decyltetradecanoic acid

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:

2015-09-15 to 2015-12-15

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Concentrations: Nominal: 100 mg/l
Mean Measured: 22.8 µg/l
- Sample storage conditions before analysis: All samples were stored at room temperature until sample preparation and in an autosampler until start of analysis, if necessary.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: A dispersion was prepared with dilution water two days prior to the start of exposure (0 h). 100 mg/L of the test item will be weighed on a glass slide and inserted into a brown glass bottle with an appropriate amount of dilution water. This dispersion was stirred for 48 hours with 1100 rpm at room temperature. Then undissolved particles were removed by membrane filtration (membrane filter 0.2 µm, RC, MACHEREY-NAGEL). The filter was saturated in order to avoid adsorption during the filtration. The first 50 mL filtrate were discarded. The filtration was interrupted for ca. 15 minutes to allow for adsorption and saturation of the filter material with dissolved test item. Thereafter, the filtration was continued. The next 50 mL were discarded. The following filtrate, i.e. the saturated solution, was used in the test. During filtration the filter was always kept covered. This procedure was repeated for daily renewal of the test media.

- Controls: Dilution water.
- Evidence of undissolved material (e.g. precipitate, surface film, etc): No

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: Danio rerio
- Source: All fish used in the test were gained at DR. NOACK-LABORATORIEN from a single breeding stock (supplier: Umweltbundesamt, Schichauweg 58, 12307 Berlin, Germany).
- Feeding during test: no


ACCLIMATION
- Acclimation period: Zebrafish with at least 12 days of acclimatisation and mortality < 5 % within these days prior to the start of exposure were used for testing. No disease treatments were administered throughout holding and testing.
- Acclimation conditions: the same as test
- Type and amount of food: Sera vipan; SERA GMBH, 52518 Heinsberg, Germany
- Feeding frequency: Food was provided 3 times per week. The amount of food was 4 % of the fish body weight per feeding day. The test fish were not fed 24 h before test start.

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

69 mg/L as CaCO3

Test temperature:

range 21.8 - 22.3 °C

pH:

range 7.22 - 7.61

Dissolved oxygen:

not mentioned, 83 - 100 % oxygen saturation

Nominal and measured concentrations:

Nominal: 100 mg/l
Mean Measured: 22.8 µg/l.

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass aquaria of 3 L were used (dimensions 11.5/13/20 cm)
- test volume: About 2 L per vessel
- Aeration: No
- Renewal rate of test solution (frequency/flow rate): daily renewal
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 7
- No. of vessels per control (replicates): 7

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: test medium, acc. to OECD Series, No. 23 (2000)6

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 12 h dark/ 12 h light
- Light intensity: 0.1 – 10 µmol • m-2 • s-1 (corresponding to approximately 7 – 750 Lux)


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :

TEST CONCENTRATIONS
- Range finding study: not required
- Test concentration: 100 mg/L (saturated solution)
- Results used to determine the conditions for the definitive study: based on the results of the acute daphnia and algae test on 2-decyltetradecanoic acid: no toxicity in the range of water solubility

Reference substance (positive control):

not required

Remarks:

according to the guideline

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

loading rate WAF

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

loading rate (WAF)

Basis for effect:

mortality (fish)

Sublethal observations / clinical signs:

Discussion of analytical results: The estimated water solubility of the test item is low with calculated concentrations of ≤ 0.0122 µg/L. Due to the high loading level (100 mg/L) of the test item compared to the calculated water solubility filtration of the stock solution was necessary to remove undissolved particles. Although the calculated value does not factor the inherent matrix effects of the dilution medium onto solubility and therefore a definitive value of maximum solubility in the test medium cannot be assumed, the formation of a saturated solution is expected. Adverse effects like variability of temperature or salt concentration in the test medium may influence solubility of the test item. Variance in analytical recoveries between different saturated solutions measured throughout the study show the sensitivity of the over-saturated solution to environmental conditions. Formation of mycelia, concentration gradients or formation of emulsions may emerge and result in variant results during analytical evaluation (higher than and below limit of quantification). It is considered that the analysed samples during the course of the study are mainly obtained from over-saturated solutions and therefore lead to over-estimation of the solubility. Since no effects were observed in the highest loading rate of 100 mg/L, effect values are given based nominal and geometric mean measured concentrations of the test item.

Validity criteria fulfilled:

yes

Conclusions:

In this study, the saturated solution of the test item 2-decyltetradecanoic acid was found to have no effect on the vitality of zebrafish after 96 hours. No effects were found up to the maximum water solubility level (estimated 0.0122 µg/L), which is below the nominal loading level of the saturated solution of 100 mg/L. Therefore, no effects were found in the range of water solubility of the test item.

Executive summary:

The acute toxicity of the test item 2 -decyltetradecanoic acid to fish (zebrafish) was determined according to the OECD Guideline for Testing of Chemicals No. 203 (1992) and the EU Council Regulation (EC) No. 440/2008/Method C.1 (2008). The test item is a colourless to pale white solid. A saturated solution was prepared with a nominal loading rate of 100 mg test item/L. The dispersion was stirred for 48 hours at room temperature. Then undissolved particles were removed by membrane filtration through a saturated filter (membrane filter 0.2 µm, RC, MACHEREY-NAGEL). The filtrate, i. e. the saturated solution, was used in the test. A semi-static test with daily renewal of the test media was performed as a limit test using the saturated solution. The test had a duration of 96 hours. 7 zebrafish (test system) were exposed to the limit loading rate and the control, respectively. The water quality parameters (pH-value, temperature and oxygen saturation) measured after 0, 24, 48, 72 and 96 h, were determined to be within the acceptable limits. Analytical evaluation of the saturated solution of 2 -decyltetradecanoic acid and the control were carried out from freshly prepared media after 0 and 72 hours and from corresponding aged test media after 24 and 96 hours by LC-MS/MS. In the beginning of the first interval, a test item concentration of 40.5 µg/L was observed. In the end of the first interval, a concentration of 66.2 µg/L was measured in the limit solution. The values for the second interval were below the limit of quantification of 20 µg/L. To account for the low water solubility of the test item, all effect values given are based on the nominal test item concentrations and the geometric test item concentrations of 2 -decyltetradecanoic acid. In this study, no effects of 2 -decyltetradecanoic acid were observed on the test system after 96 hours. No effects were found up to the maximum water solubility level (estimated ≤ 0.0122 µg/L), which is below the nominal loading level of 100 mg/L. Therefore, no effects were found in the range of water solubility of the test item. It should be considered that the measured concentrations are higher than the calculated water solubility.  

Description of key information

In the acute fish study according to OECD 203, the saturated solution of the test item 2-decyltetradecanoic acid was found to have no effect on the vitality of zebrafish after 96 hours. No effects were found up to the maximum water solubility level (estimated 0.0122 µg/L), which is below the nominal loading level of the saturated solution of 100 mg/L. Therefore, no effects were found in the range of water solubility of the test item.