Ammonium benzoate

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

09 April 2018 - 05 July 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Ammonium benzoate

EC Number:

217-468-9

EC Name:

Ammonium benzoate

Cas Number:

1863-63-4

Molecular formula:

C7H6O2.H3N

IUPAC Name:

ammonium benzoate

Test material form:

solid: crystalline

Details on test material:

- State of aggregation: solid
- Particle size distribution: median particle size D50 = 98 µm
- Mass median aerodynamic diameter (MMAD): not determined
- Geometric standard deviation (GSD): not determined
- Shape of particles: not determined
- Surface area of particles: not determined
- Crystal structure: not determined
- Coating: none
- Surface properties: none known
- Density: 1.26
- Moisture content: ca. 1.5 %
- Residual solvent: none known
- Activation: none
- Stabilisation: none
- Other: none

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: 608031
- Expiration date of the lot/batch: 25. Oct. 2018
- Purity test date: 25. Oct. 2016 (CoA)

RADIOLABELLING INFORMATION (if applicable)

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: closed vessel dark and dry at room temperature 20 ± 5°C
- Stability under test conditions: assumed stable
- Solubility and stability of the test substance in the solvent/vehicle: assumed soluble and stable
- Reactivity of the test substance with the solvent/vehicle of the cell culture medium: assumed non-reactiv

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
no specific treatment

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

No sample preparation was performed.

Test solutions

Vehicle:

no

Details on test solutions:

A solution containing 100.2 mg/L in dilution water was prepared and used for the test.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

6.3.1 Specification
Species Daphnia magna
Authority STRAUS
Strain Berlin
Sex female
Age between 0 and 24 hours
Origin Umweltbundesamt Berlin
In-house breeding since 27. September 2007
Selection of the test system was made following the proposal of the guidelines.
6.3.2 Animal Husbandry
Daphnia magna is bred in the LAUS GmbH throughout the year. The animals are kept for the use in toxicity tests. They multiply by parthenogenesis, thus being genetically identical. The husbandry is performed similar to the method described in the OECD guideline, following SOP 115 002 01 („Zucht und Hälterung von Daphnia magna STRAUS“), Version 12 from 02. Feb. 2015.
Vessels preserving glasses, nominal volume 2 L
Medium M4-Medium (recipe of ELENDT)
Food green algae (Desmodesmus subspicatus)
Medium renewal twice a week
Photo period 16/8 hours, using neon tubes
Temperature 20  2 °C

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Post exposure observation period:

none

Test conditions

Hardness:

250 mg CaCO3 /L

Test temperature:

19.7 - 21.2°C

pH:

7.8

Dissolved oxygen:

between 8.4 and 9.3 mg/L

Salinity:

not stated

Conductivity:

not stated

Nominal and measured concentrations:

nominal: 100 mg/L
measured (beginning): 100.67 mg/L
measured (end): 109.23 mg/L

Details on test conditions:

7.1 Selection of Daphnia
20 hours before the start of the test, the adult animals were separated from the young. 1.5 hours before test start, the adults were caught with the help of a glass tube, and the new-born Daphnia, aged between 0 and 18.5 hours, were sieved from the medium and imme-diately placed into a beaker containing dilution water. After the settling-in period, animals which showed no apparent damage were used for the test.
Switching from M4-medium (husbandry) to Dilution water (test) has been shown not to cause any detrimental effects for test Daphnia.
7.2 Study Performance
Using a glass tube, the Daphnia were caught and lifted from the beaker. They were put on a small sieve, and the medium surrounding the animals was sucked off using absorbent paper. Immediately after that, the animals were put into the respective test solution.
The test vessels were left to stand for 48 hours. After 24 and 48 hours, the immobilised Daphnia were counted. Daphnia are considered immobilised when they do not perform any movements or are only able to move their antennae when the beaker is gently agi-tated. Daphnia which are trapped at the surface of the test solution are also considered immobilised.
The pH, the concentration of dissolved oxygen and the content of the test item in the test vessels were measured at the beginning and at the end of the test.
7.3 Experimental Conditions
Date of performance 24. Apr. - 26. Apr. 2018
Treatments 100 mg/L (nominal) limit test
The concentration to be tested is based on the result of a non-GLP pre-test.
Temperature 19.7 - 21.2°C
Duration 48 hours
Observation times 24 and 48 hours
Medium renewal none
Test vessels glass beakers, nominal volume 50 mL, tall shape
Replicates (Treatments) 4 vessels, each containing 20 ± 5 mL test solution and 5 Daphnia
Replicates (Blank control) 4 vessels, each containing 20 ± 5 mL dilution water and 5 Daphnia

Reference substance (positive control):

yes

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 2

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 3

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 4

Key result

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

VALIDITY
• Immobilisation in the controls may not exceed 10 %.
Immobilisation in the controls was 0 %.
• The concentration of dissolved oxygen at the end of the test must be at least 3 mg/L. The lowest concentration of dissolved oxygen at the end of the test was 8.4 mg/L.

Results with reference substance (positive control):

Potassium dichromate K2Cr2O7 (CAS No. 7778-50-9) was used as positive control in a current reference study (201714R201). The 24h-EC50 value was determined as 1.9 mg/L. The value was within the requested range for the 24h-EC50 between 0.6 - 2.1 mg/L of po-tassium dichromate K2Cr2O7 as specified in the OECD guideline. Since the fits showed sufficient statistical correspondence of the data with the dose-response-equation, this reference study can be considered valid.

Reported statistics and error estimates:

none

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Ammonium Benzoate had no effect on Daphnia Magna at a concentration of 100 mg/L under the test conditions.

Executive summary:

One valid experiment was performed.

The study was performed as a limit test using a concentration at 100 mg/L. For the test concentration and the blank control, 20 Daphnia were exposed to the test item for 48 hours in a static test system. After 24 and 48 hours, the immobilised Daphnia were counted.

The treatment showed no toxicity and none of the animals was immobilised in the blank control.

Potassium dichromate K₂Cr₂O₇(CAS No. 7778-50-9) was used as positive controlin a current reference study to assure that the test conditions are reliable.

 

At the beginning and at the end of the test, the content of the test item in the test solutions was determined usingHPLC-UVdetermination. The concentration determined at the start of the test was 100.67% of the nominal concentration. At the end of the test the determined concentration was 109.23% of the nominal concentration. Therefore, the determination of the biological results was based on the nominal concentration.

The following results were determined for the test itemAmmonium Benzoate(species:Daphnia magna).

 

48h-NOEC≥100 mg/L
48h-LOEC > 100 mg/L
24h-EC₅₀> 100 mg/L
48h-EC₅₀> 100 mg/L