Fatty acids, C12-14 (even numbered), methyl ester

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

11 - 18 Oct 2013

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

GLP guideline study with acceptable restrictions: The study was not performed according to a standard acute toxicity test but a long-term toxicity test. However, the adult mortality after 7d chronic exposure is judged as valid acute toxicity endpoint.

Qualifier:

according to guideline

Guideline:

other: OECD 211

Principles of method if other than guideline:

Long-term toxicity test according to OECD guideline 211. Adult mortality after 7d exposure was used to assess the chronic acute toxicity

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: An appropriate amount of the test item was weighed for each loading level and transferred in a brown glass bettle with an appropriate amount of dilution water. The test item dispersion were shaken for 24 hours with 20 rpm at room temperature. After a separation phase of 24 hours, undissolved particles were removed by membrane filtration (membrane filter 0.45 μm, RC, MACHEREY-NAGEL). During filtration, the filter was always covered. The resulting Water Soluble Fractions (WSF) were used in the test. This procedure was carried out 2 days prior to the start of each exposure interval on study day -2 until day 18 for the daily renewal.
- Evidence of undissolved material (e.g. precipitate, surface film, etc): no

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Strain: clone 5
- Source: inhouse culture originally obtained by Institut für Wasser-, Boden- und Lufthygiene (WaBolu)
- Age at study initiation (mean and range, SD): < 24h
- Method of breeding: In glass vessels (2 - 3 L capacity) with approximately 1.8 L culture medium, at 20 ± 2°C, in an incubator, 16 h illumination; light intensity of max. 20 μE-m-2 . s-1
- Feeding during test
- Food type/Amount: Pseudokirchneriella subcapitata (0.162 - 0.294 ml) and Desmodesmus subspicatus (0.290 - 0.319 ml) suspension was provided as food corresponding to 0.2 mg C per Daphnia and day.
- Frequency: daily

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Hardness:

160 -208 mg/L as CaCO3

Test temperature:

20.6 - 22 °C

pH:

7.09 - 7.93

Dissolved oxygen:

4.82 - 9.06 mg/L

Nominal and measured concentrations:

Nominal: 1, 3.16, 10, 31.6 and 100 mg/L as loading rate WSF (water soluble fraction)

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass beakers (5 (ID) x 8 (H) cm), 100 ml capacity with 50 mL test media
- Renewal rate of test solution: daily
- No. of organisms per vessel: 1
- No. of vessels per concentration (replicates): 10
- No. of vessels per control (replicates): 10

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Elendt M4
- Intervals of water quality measurement: The water quality parameters (i.e. pH-values, dissolved oxygen concentration, total hardness and water temperature) were measured once within 7 days, at the start (0 h) and at the end (24 h) of an exposure interval, in one replicate of the highest loading evel and the control. The water quality parameters at the start of the exposure interval were measured in an additional replicate without daphnids of the highest loading level and the control. At the end of the exposure interval, the water quality parameters were measured in a test vessel of the highest loading level and the control, which contained daphnids and food algae. The temperature in the incubator was recorded throughout the exposure period with a thermo hygrograph.

OTHER TEST CONDITIONS
- Photoperiod: 16/8h light/dark cycle
- Light intensity: max. 20 µE/m2/s

EFFECT PARAMETERS MEASURED: Mortality of adult daphnids was recorded after 7 days exposure time

TEST CONCENTRATIONS
- Range finding study
- Test concentrations: 1, 10, 100 mg/L as loading rate WAF
- Results used to determine the conditions for the definitive study: The preliminary testing (acute immobilisation test) has shown toxic (mortality) and physical effects (daphnids being trapped at the water surface) on Daphnia magna, when tested with Water Accommodated Fractions of the test item Fatty acids, C12-14 (even numbered), methyl ester. Therefore, it was considered to perform a full dose-response tes~ with Water Soluble Fractions of the test item.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Key result

Duration:

7 d

Dose descriptor:

EL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

No mortality was observed in the control and any treatment after 7 days exposure time.

Results with reference substance (positive control):

- Results with reference substance valid: yes
- EC50: 1.65 mg/L
- Other: The ECso-value of the reference item potassium dichromate after 24 h is within the prescribed concentration range of 0.6 - 2.4 mg/L of quality criteria according to AQS P 9/2 (02/2000) for daphnids clone 5 cultured in Elendt M4 medium. The ECso-value of the reference item is also within the recommended range of 0.6 - 2.1 mg/L according to OECD-Guideline 202.

Table 1: Results of preliminary test

Nominal loading of the WAF [mg/L]	Immobilisation [%]
	24h			48h
	Replicates			Replicates
	1	2	3	1	2	3
100	100*	100*	100	100	100	100
10	70*	70*	70	100*	100*	100
1	0	0	0	0	0	0
control	0	0	0	0	0	0

 

* = most of the daphnids were trapped on the surface of the test loading. Immobile and dead daphnids were observed. A layer of undissolved test item was observed at the WAFs with nominal loadings of 10 and 100 mg/L.

Validity criteria fulfilled:

yes

Conclusions:

The short-term toxicity of the substance to aquatic invertebrates is assessed using results obtained in a long-term study performed according to OECD guideline 211 and GLP. Based on the 7d-EC50 value of > 100 mg/L (loading rate WSF) the substance is very likely not acute harmful to aquatic invertebrates.

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because a long-term aquatic toxicity study on invertebrates is available

Description of key information

In accordance with Regulation (EC) No. 1907/2006, Annex VII, Column 2, 9.1.1, short-term toxicity testing on aquatic invertebrates is not required since a long-term aquatic toxicity study on invertebrates is available. Supporting information: EC50 (7d) > 100 mg/L (loading rate WSF, mortality) for Daphnia magna (OECD 211)

Additional information

No study investigating the short-term toxicity of Fatty acids, C12 -14 (even numbered), methyl ester according to a standard acute toxicty test is available. In accordance with Regulation (EC) No. 1907/2006, Annex VII, Column 2, 9.1.1, short-term toxicity testing on aquatic invertebrates is not required since a long-term aquatic toxicity study on invertebrates is available for Fatty acids, C12-14 (even numbered), methyl ester.

However, adult mortality after 7 days chronic exposure as recorded in the long-term toxicity test can be used to assess the acute chronic toxicity of the substance to aquatic invertebrates (Scheerbaum 2014). The long-term toxicity of Fatty acids, C12-14 (even numbered), methyl ester (CAS 308065-15-8) to aquatic invertebrates was investigated according to OECD guideline 211 and GLP using Daphnia magna as test organism. A full dose-response test with Water Soluble Fractions of the test item was performed since preliminary testing (acute immobilisation test) has shown toxic (mortality) and physical effects (daphnids being trapped at the water surface) on Daphnia magna, when tested with Water Accommodated Fractions of the test item. Nominal loading rate WSFs between 1 and 100 mg/L were tested over an exposure time of 21 days. No mortality was observed in the control and any treatment after 7 days. Thus, a 7d-EC50 value is determined to be > 100 mg/L.