L-Glutamic acid, N-coco acyl derivs., disodium salts

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

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

The temperature for the main test was slightly out of the demanded range (17.8 to 21.6 °C instead of 18 to 22 °C). Taking a mean of 19.7 °C the values are not varying more than ± 2 °C. Since no significant effects on reproductive output occurred during the test, this deviation is considered to be uncritical and not invalidating the test. The deviation was signed and assessed by the study director on March 03, 2016.

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Concentrations: all treatments
- Sampling method: Samples for analytical determinations were taken from the new and the old solutions at each medium renewal.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: A stock solution containing nominal 100 mg/L in dilution water was prepared. The solutions of the amount needed were prepared by dilution of this stock solution with dilution water.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
-Strain: Berlin
- Source: in-house culture originally obtained from Umweltbundesamt , Berlin
- Age at study initiation (mean and range, SD): < 24h
- Feeding during test: Yes
- Food type: green algae (Desmodesmus subspicatus), 0.15 - 0.2 mg OC/animal/day (amount of carbon was based on photometric measurement)

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Hardness:

267 - 445 mg/L as CaC03

Test temperature:

17.8 - 21.6 °C; Taking a mean of 19.7 °C the values were not varying more than ± 2 °C.

pH:

7.7 - 8.5

Dissolved oxygen:

8.4 - 9.6 mg/L

Nominal and measured concentrations:

Nominal: 1.1, 2.2., 4.6, 10 and 22 mg product/L
Nominal: 0.275, 0.55, 1.15, 2,5 and 5.5 mg AS/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 mg glass beakers with 80 mL test solution
- Aeration: none
- Renewal rate of test solution (frequency/flow rate): three times a week
- 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: A synthetic fresh water (Elendt M4) is used as media for culture and test purposes
- TOC content: < 2 mg/L
- Culture medium different from test medium: no
- Intervals of water quality measurement: pH and oxygen content and hardness were measured in the new and the old test solutions (control and highest test concentration) once a week.

OTHER TEST CONDITIONS
- Photoperiod: 16:8 light/dark
- Light intensity: 1000 lux

EFFECT PARAMETERS MEASURED: Mortality, reproduction and other sublethal effects were measured daily.

Reference substance (positive control):

no

Key result

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

>= 5.5 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

reproduction

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

>= 22 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Details on results:

- Mortality of parent animals: 20%

The content of the test item in the test solutions was estimated by DOC measurement. Only in the highest concentrated treatment 22 mg/L, the measured DOC concentrations in the fresh prepared solutions showed the presence of dissolved test item. The measured DOC concentration in the fresh prepared solution of this treatment ranged from 3.6 – 4.0 mg/L. These concentrations lay in the range of the theoretical value of 3.1 mg/L, based on a carbon content of the test item of 14.43 %. The DOC concentration in the other treatments and the blank control were in the same range. Therefore, the determination of the results was based on the nominal concentrations.

Fecundity

Treatment [mg/L]	Total offspring	Surviving parental animals	Mean offspring/surviving parental animal	Inhibition of reproduction [%]
control	550	8	69	0
1.1	792	10	79	-15
2.2	684	10	68	1
4.6	652	10	65	5
10	720	9	80	-16
22	909	10	91	-32

Validity criteria fulfilled:

yes

Conclusions:

The test substance is not harmful to aquatic invertebrates at chronic exposure.

Description of key information

NOEC (21d) >= 5.5 mg/L (AS, nominal) for Daphnia magna (OECD 211)

Additional information

One study investigating the long-term toxicity of l-Glutamic acid, N-coco acyl derivs., disodium salts (CAS No. 68187-30-4) to aquatic invertebrates is available. The study was performed according to GLP and OECD guideline 211 using Daphnia magna as test organism (Muckle 2016). Nominal concentrations between 1.1 and 22 mg/L were tested, which correspond to test concentrations of 0.275 to 5.5 mg/L based on active matter. Nominal concentrations were confirmed using TOC analysis. No inhibition of reproduction was observed in any treatment. Thus, a 21d-NOEC is determined to be > 5.5 mg AS/L based on nominal concentrations.