N-(4-(methoxybenzyl))-N,N-dimethylanilinium hexafluoroantimonate

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

effects on growth of green algae

Remarks:

Pseudokirchneriella subcapitata

Type of information:

experimental study

Adequacy of study:

key study

Study period:

22 Sept - 21 Nov 2022

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Freshwater Alga and Cyanobacteria, Growth Inhibition Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: “Act on Specified Standards and Management Standards for Chemical Testing Laboratory” Notification No. 2022-9, Ministry of Environment, Republic of Korea (Jan. 11, 2022)

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source (i.e. manufacturer or supplier): : King Industries, Inc. 1 Science Road, Norwalk, CT 06852, USA
- Purity, 99.8%

RADIOLABELLING INFORMATION (if applicable)
- Radiochemical purity:
- Specific activity:
- Locations of the label:
- Expiration date of radiochemical substance:

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material:
- Stability and homogeneity of the test material in the vehicle/solvent under test conditions (e.g. in the exposure medium) and during storage:
- Stability in the medium, i.e. sensitivity of the test material to hydrolysis and/or photolysis:
- Solubility and stability of the test material in the solvent/vehicle and the exposure medium:
- Reactivity of the test material with the incubation material used (e.g. plastic ware):

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing (e.g. warming, grinding): Inoculum culture was conducted for 72 hours prior to the test. Exponential growth phase was used to test the freshwater alga. There was no observed abnormal shape. Growth rate was 197.75 times during inoculum.
- Preliminary purification step (if any):
- Final concentration of a dissolved solid, stock liquid or gel:
- Final preparation of a solid (e.g. stock crystals ground to fine powder using a mortar and pestle):

FORM AS APPLIED IN THE TEST (if different from that of starting material)
- Specify the relevant form characteristics if different from those in the starting material, such as state of aggregation, shape of particles or particle size distribution:

INFORMATION ON NANOMATERIALS
- Chemical Composition:
- Density:
- Particle size & distribution:
- Specific surface area:
- Isoelectric point:
- Dissolution (rate):

TYPE OF BIOCIDE/PESTICIDE FORMULATION (if applicable)
- Description of the formulation, e.g. formulated product for foliar application; formulated product soil application; solution in organic solvent for soil application; formulated product seed treatment; solution in organic solvent seed treatment:

OTHER SPECIFICS
- Other relevant information needed for characterising the tested material, e.g. if radiolabelled, adjustment of pH, osmolality and precipitate in the culture medium to which the test chemical is added:

Analytical monitoring:

yes

Details on sampling:

Analysis of the test substance was performed in each replicate at the beginning (0 h)
and 72 h after exposure

Vehicle:

no

Test organisms (species):

Raphidocelis subcapitata (previous names: Pseudokirchneriella subcapitata, Selenastrum capricornutum)

Test type:

static

Water media type:

freshwater

Remarks:

OECD medium

Limit test:

no

Total exposure duration:

72 h

Test temperature:

22.5 - 23.0° C

pH:

6.24 - 7.9

Dissolved oxygen:

No data

Salinity:

No data

Conductivity:

No data

Nominal and measured concentrations:

Nominal concentration: 10, 20, 40, 80, 160 mg/L
Geometric mean measured: 9.243, 18.918, 37.980, 74.007, 145.815

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 mL flask
- Type (delete if not applicable): open or closed? (not stated)
- Material, size, headspace, fill volume: 100 mL
- Aeration: none

- Initial cells density: 10000 cells/mL
- Control end cells density: 1894167 cells/mL
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 3

GROWTH MEDIUM
- Standard medium used: yes


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: [counting chamber; electronic particle counter; fluorimeter; spectrophotometer; colorimeter]
- Chlorophyll measurement:
- Other: Cells throughout the study including in the cont5rol were considered normal.

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 24 h
- Justification for using less concentrations than requested by guideline:

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

73.604 mg/L

95% CI:

61.348 - < 90.453

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Key result

Duration:

72 h

Dose descriptor:

LOEC

Effect conc.:

20 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Key result

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

10 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

10 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

yield

Duration:

72 h

Dose descriptor:

LOEC

Effect conc.:

20 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

yield

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

32.847 mg/L

95% CI:

28.852 - < 37.271

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

yield

Details on results:

The biomass in the control group was increased by 189 times or more during the exposure period, and each coefficient of variation was confirmed to be acceptable in this test.
As a result of the definitive test, the mean measured concentration measured at time point 0 h and 72 h at 10.00, 20.00, 40.00, 80.00 and 160.00 mg/L were 9.243, 18.918, 37.980, 74.007 and 145.815 mg/L. These results were 92.4, 94.6, 95.0, 92.5 and 91.1 % of the nominal concentration.
Therefore, all results were determined on the basis of the nominal concentration.The 72 h ErC50 value of the test substance to Pseudokirchneriella subcapitata was determined to be 73.604 mg/L(95 % confidence limits: 61.348~90.453 mg/L), NOEC was 10.00 mg/L and LOEC was 20.00 mg/L. The 72h EyC50 value was determined to be 32.847 mg/L(95 % confidence limits: 28.852~37.271 mg/L), NOEC was 10.00 mg/L and LOEC was 20.00 mg/L. The EC50, NOEC and LOEC were based on the geometric nominal concentration.

Results with reference substance (positive control):

- Results with reference substance valid; Yes, potassium dichromate
- EC50: 0.665 mg/L (growth)
- Other:

Validity criteria fulfilled:

yes

Conclusions:

The results under the conditions of this study show that the test substance should be classified as Aquatic Chronic 3; H412.

Description of key information

The result of this study indicates that the test substance will be classified as Aquatic chronic 3; H412.

Key value for chemical safety assessment

EC50 for freshwater algae:

73.604 mg/L

EC10 or NOEC for freshwater algae:

10 mg/L