Hydrogen [4-[4-(dimethylamino)-α-(2-hydroxy-3,6-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium, monosodium salt

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

02.05.2017 - 05.05.2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Experimental test result performed using standard test guideline

Justification for type of information:

Data is from ABITEC lab report.

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Principles of method if other than guideline:

Short term toxicity of Hydrogen [4-[4-(dimethylamino)-α-(2-hydroxy-3,6-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium, monosodium salt to aquatic algae was performed according to the 201 OECD guideline in a static system.

GLP compliance:

not specified

Specific details on test material used for the study:

- Name of test material (as cited in study report): Hydrogen [4-[4-(dimethylamino)-α-(2-hydroxy-3,6-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium, monosodium salt
- Molecular formula :C27H26N2O7S2.Na
- Molecular weight: 576.623 g/mol
- Substance type:Organic
- Physical state: Deep red powder

Analytical monitoring:

not specified

Vehicle:

yes

Details on test solutions:

The stock solution 160 mg/l was prepared by dissolving deep red powder in OECD growth medium. Test solutions of required concentration were prepared by mixing the stock solution of the test sample with OECD growth medium and inoculum culture.

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Common name:
- Strain: 86.81 SAG
- Source (laboratory, culture collection): Institute of botany of the ASCR
- Initial biomass concentration: 5x10(3) cells /ml
- Method of cultivation: No data available

ACCLIMATION - No data available
- Acclimation period:
- Culturing media and conditions (same as test or not):
- Any deformed or abnormal cells observed:

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Remarks on exposure duration:

±1 hour

Test temperature:

23±2°C

pH:

Test at highest concentration: 7.5 (Change to 7.6 during tests)
Control: 8.0 (changed to 7.3 during test)

Nominal and measured concentrations:

0, 10, 20, 40, 80 and 160 mg/l nominal concentrations

Details on test conditions:

TEST SYSTEM
- Test vessel: 50 ml Glass vessel
- Type (delete if not applicable): closed (with air permeable stopper)
- Sample volume: 7.5 ml
- Initial cells density: 5x10(3) cells/ml
- No. of vessels per concentration (replicates): 3 for sample, 6 for control

GROWTH MEDIUM
- Standard medium used: yes

OTHER TEST CONDITIONS
- Adjustment of pH: No
- Photoperiod: Continuous
- Light intensity and quality: 6000-8000 lx

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: microscope with counting chamber Cyrus I or electronic particle counter.
- Other: ErC50 was calculated using non-linear regression by the software Prism 4.0

Reference substance (positive control):

yes

Key result

Duration:

72 h

Dose descriptor:

other: ErC50

Effect conc.:

58.6 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95 % CI was 46.7-73.6 mg/l

Results with reference substance (positive control):

Results with reference substance valid
- EC50: 0.75 mg/L

Reported statistics and error estimates:

ErC50 is calculated from the inhibition of growth rate by non-linear regression using software Prism 4.0, GraphPad.

Validity criteria fulfilled:

yes

Conclusions:

The median effective concentration (EC50) for the test substance Hydrogen [4-[4-(dimethylamino)-α-(2-hydroxy-3,6-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium, monosodium salt, in Desmodesmus subspicatus was determined to be 58.6 mg/L on the basis of effects on growth rate in a 72 hour study. Based on the ErC50 value, indicates that the substance is likely to be hazardous to aquatic invertebrates and can be classified as aquatic chronic 3 as per the CLP classification criteria.

Executive summary:

Short term toxicity of  Hydrogen [4-[4-(dimethylamino)-α-(2-hydroxy-3,6-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium, monosodium salt to aquatic algae Desmodesmus subspicatus (previous name: Scenedesmus subspicatus) was performed according to the 201 OECD guideline in a static system.

Test conducted at 0, 10, 20, 40, 80 and 160 mg/l nominal concentrations. The stock solution 160 mg/l was prepared by dissolving deep red powder in OECD growth medium. Test solutions of required concentration were prepared by mixing the stock solution of the test sample with OECD growth medium and inoculum culture. Chemical exposed to Desmodesmus subspicatus strain 86.81 SAG were 5x10(3) cells /ml Initial biomass concentration were used. 3 replicates for sample and 6 replicates for control was used.

Effects on growth rate were observed for 72 hours. With the test substance one positive control Potassium dichromate (K2Cr2O7) was also run simultaneously. After the exposure of chemical, effect concentration ErC50 was calculated using nonlinear regression by the software Prism 4.0.

The median effective concentration (EC50) for the test substance Hydrogen [4-[4-(dimethylamino)-α-(2-hydroxy-3,6-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium, monosodium salt, in Desmodesmus subspicatus was determined to be 58.6 mg/L on the basis of effects on growth rate in a 72 hour study. Based on the ErC50 value, indicates that the substance is likely to be hazardous to aquatic invertebrates and can be classified as aquatic chronic 3 as per the CLP classification criteria.

Description of key information

The median effective concentration (EC50) for the test substance Hydrogen [4-[4-(dimethylamino)-α-(2-hydroxy-3,6-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium, monosodium salt, in Desmodesmus subspicatus was determined to be 58.6 mg/L on the basis of effects on growth rate in a 72 hour study. Based on the ErC50 value, indicates that the substance is likely to be hazardous to aquatic invertebrates and can be classified as aquatic chronic 3 as per the CLP classification criteria.

Key value for chemical safety assessment

EC50 for freshwater algae:

58.6 mg/L

Additional information

Short term toxicity of  Hydrogen [4-[4-(dimethylamino)-α-(2-hydroxy-3,6-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium, monosodium salt to aquatic algae Desmodesmus subspicatus (previous name: Scenedesmus subspicatus) was performed according to the 201 OECD guideline in a static system.

Test conducted at 0, 10, 20, 40, 80 and 160 mg/l nominal concentrations. The stock solution 160 mg/l was prepared by dissolving deep red powder in OECD growth medium. Test solutions of required concentration were prepared by mixing the stock solution of the test sample with OECD growth medium and inoculum culture. Chemical exposed to Desmodesmus subspicatus strain 86.81 SAG were 5x10(3) cells /ml Initial biomass concentration were used. 3 replicates for sample and 6 replicates for control was used.

Effects on growth rate were observed for 72 hours. With the test substance one positive control Potassium dichromate (K2Cr2O7) was also run simultaneously. After the exposure of chemical, effect concentration ErC50 was calculated using nonlinear regression by the software Prism 4.0.

The median effective concentration (EC50) for the test substance Hydrogen [4-[4-(dimethylamino)-α-(2-hydroxy-3,6-disulphonato-1-naphthyl)benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium, monosodium salt, in Desmodesmus subspicatus was determined to be 58.6 mg/L on the basis of effects on growth rate in a 72 hour study. Based on the ErC50 value, indicates that the substance is likely to be hazardous to aquatic invertebrates and can be classified as aquatic chronic 3 as per the CLP classification criteria.