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

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2014

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

Deviations:

no

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: Effects on the reproduction capacity and other test item-related effects on parameters such as intrinsic rate of natural increase, occurrence of aborted eggs and stillborn juveniles, time of release of the first brood and adult mortality recorded daily throughout an exposure time of 21 days.

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:

21 d

Dose descriptor:

NOELR

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

(WSF)

Basis for effect:

reproduction

Details on results:

No significant effects on the reproductive output or any other measured endpoint were observed in the control and any treatment after 21 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 long-term toxicity of the substance to aquatic invertebrates is investigated according to OECD guideline 211 and GLP. Based on the 21d-NOELR value of > 100 mg/L (loading rate WSF) the substance is very likely not harmful to aquatic invertebrates at chronic exposure.

Executive summary:

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 significant effects on the reproductive output or any other measured endpoint were observed in the control and any treatment after 21 days exposure time. Thus, the 21d-NOELR value is determined to be >= 100 mg/L.

Description of key information

NOEC (21 d) >= 100 mg/L (loading rate WSF) for reproduction of Daphnia magna (OECD 211)