N,N-bis(carboxymethyl)glycine, compound with 2-aminoethanol (1:3)

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

22/02/2005 - 04/05/2005

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

other: ISO 14669 (1999) Water Quality - Determination of acute lethal toxicity to marine cope

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: ISO 5667-16 (1998) Water Quality Sampling - Guidance on biotesting of samples

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Solubility and stability of the test substance in the solvent/vehicle: Dissolved at 10 000 mg/L


TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: Dissolved in seawater
- Final preparation of a solid: Dissolved in seawater

FORM AS APPLIED IN THE TEST (if different from that of starting material) Aqueous, in solution

Analytical monitoring:

no

Details on sampling:

- Concentrations: 1000, 1800, 3200, 5600, 10 009 mg/L (nominal concentrations)
- Sampling method: Mortality within a control

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Test material dissolved in seawater
- Controls: 4 mortality controls (1 replicate each). 5 positive controls of 0.1, 0.32, 0.56, 1.0 and 1.8 mg/L (2 replicates per concentration).

Test organisms (species):

other aquatic crustacea: Acartia tonsa

Details on test organisms:

TEST ORGANISM
- Common name: Acartia tonsa

ACCLIMATION
- Acclimation period:
- Acclimation conditions (same as test or not): No
- Type and amount of food: Mixed algal diet (2-4 species)

Test type:

static

Water media type:

saltwater

Limit test:

no

Total exposure duration:

48 h

Remarks on exposure duration:

Measurements taken at 24 and 48 hours.

Test temperature:

17.9 - 21.3 °C

pH:

At 0 hours, pH 8.09-8.13
At 48 hours, pH 7.99-8.13

Dissolved oxygen:

94-97%

Conductivity:

48.5-49.7 mS/cm.

Nominal and measured concentrations:

Nominal concentrations for test substance were 1000, 1800, 3200, 5600, 10 009 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: crystallising dishes
- Type (delete if not applicable) closed, soda glass watch cover
- Material, size, headspace, fill volume: borosilicate glass, 50 ml
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Natural seawater from Scapa Flow, Orkney.
- Particulate matter: Filtered seawater
- Conductivity: 48.0 - 49.9 mS/cm
- Culture medium different from test medium: Yes
- Intervals of water quality measurement: Daily


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Mortality of population over time.

RANGE-FINDING STUDY
- Test concentrations: Nominal concentrations 1, 10, 100, 1000 mg/ L
- Results used to determine the conditions for the definitive study: Yes

Reference substance (positive control):

yes

Remarks:

3,5 Dichlorophenol

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

2 675 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Key result

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

1 553.85 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

48 h

Dose descriptor:

other: LC90

Effect conc.:

2 733.33 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

- Mortality of control: 0%
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: No
- Effect concentrations exceeding solubility of substance in test medium: No

Results with reference substance (positive control):

- Results with reference substance valid? Yes
- Limit test: No
- Dose-response test: Yes, 1.8, 1.0, 0.56, 0.32 and 0.1 mg/L
- ECx: LC50

Validity criteria fulfilled:

yes

Conclusions:

The test substance has a LC50 of 2675.00 mg/L for 24 hours and 1553.85 mg/L for 48 hours, an LC90 value of 2733.33 mg/L for 48 hours and a NOEC value of 1000.00 mg/L for 48 hours.

Executive summary:

The study assessed the short-term toxicity of monoethanolamine salt of nitrilotriacetic acid to aquatic invertebrates. This study was performed in compliance with GLP and follows the guidelines of ISO 14669 (1999) Water Quality - Determination of acute lethal toxicity to marine copepods (Copepoda; Crustacea) and ISO 5667 - 16 (1998) Water Quality Sampling - Guidance on biotesting of samples.

All validity criteria were met and the test organisms used was Acartia tonsa. The rangefinding test exhibited no effect at the maximum concentration (0% proportional mortality response at 48 hours). Therefore, in the definitive test nominal concentrations of 1000, 1800, 3200, 5600, 10 000 mg/L were used with 2 replicates per concentration per time point measured (10 organisms per replicate). Four mortality controls were present (0 mg/L test material) which showed a proportional mortality response of 0% over 48 hours for 1 replicate per concentration, each with 10 -11 organisms. Five positive controls were present (0.1, 0.32, 0.56, 1.0 and 1.8 mg L-1 3,5 Dichlorophenol) with 2 replicates per concentration each with 9 - 11 organisms per replicate giving a 48 hour LC50 value of 0.51 mg/L. Monoethanolamine Salt of Nitrilotriacetic Acid exhibited a 48h LC50 value of 1553.85 mg/L (dilution series) to the marine copepod Acartia tonsa in the aqueous phase.

Description of key information

The study assessed the short-term toxicity of monoethanolamine salt of nitrilotriacetic acid to aquatic invertebrates. This study was performed in compliance with GLP and follows the guidelines of ISO 14669 (1999) Water Quality - Determination of acute lethal toxicity to marine copepods (Copepoda; Crustacea) and ISO 5667 - 16 (1998) Water Quality Sampling - Guidance on biotesting of samples.

All validity criteria were met and the test organisms used was Acartia tonsa. The rangefinding test exhibited no effect at the maximum concentration (0% proportional mortality response at 48 hours). Therefore, in the definitive test nominal concentrations of 1000, 1800, 3200, 5600, 10 000 mg/L were used with 2 replicates per concentration per time point measured (10 organisms per replicate). Four mortality controls were present (0 mg/L test material) which showed a proportional mortality response of 0% over 48 hours for 1 replicate per concentration, each with 10 -11 organisms. Five positive controls were present (0.1, 0.32, 0.56, 1.0 and 1.8 mg/L 3,5 Dichlorophenol) with 2 replicates per concentration each with 9 - 11 organisms per replicate giving a 48 hour LC50 value of 0.51 mg/L. Monoethanolamine Salt of Nitrilotriacetic Acid exhibited a 48h LC50 value of 1553.85 mg/L (dilution series) to the marine copepod Acartia tonsa in the aqueous phase.

Key value for chemical safety assessment

Marine water invertebrates

Marine water invertebrates

Effect concentration:

1 553.85 mg/L