Sodium 3-nitrobenzenesulphonate

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Experimental test result performed using standard test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Principles of method if other than guideline:

Short term toxicity of test chemical to aquatic algae was performed according to the OECD Guideline 201 (Alga, Growth Inhibition Test) in a static system.

GLP compliance:

not specified

Analytical monitoring:

not specified

Vehicle:

not specified

Details on test solutions:

The solution of white pearl 100 mg/l was prepared by dissolving the substance in OECD growth medium.

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:

yes

Total exposure duration:

72 h

Remarks on exposure duration:

±1 hour

Test temperature:

23±2°C

pH:

Sample: 8.1 (changed to 7.8 during test)
Control: 8.3 (changed to 9.1 during test)

Nominal and measured concentrations:

Test conducted at 100 mg/l nominal concentration

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 ml Glass vessel
- Type (delete if not applicable): closed (with air permeable stopper)
- Sample volume: 30 ml
- Initial cells density: 5x10(3) cells/ml
- No. of vessels per concentration (replicates): 6

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

Remarks:

Potassium dichromate (K2Cr2O7)

Key result

Duration:

72 h

Dose descriptor:

other: IC0

Remarks:

%

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: No inhibition were observed at 100 mg/l.

Results with reference substance (positive control):

Results with reference substance valid
- EC50: 0.65 mg/L

Reported statistics and error estimates:

The differences in means of control and sample were estimated by the t-test for independent groups at a 95 % confidence level, all individual replicates were used (STATISTICA CZ – data analysis software system, version 9.0, StatSoft, Inc.). Statistically significant differences are for p < 0.05.

Validity criteria fulfilled:

yes

Conclusions:

After the exposure of chemical with algae Desmodesmus subspicatus, no inhibition were observed after the 72 hrs. And the IC0% was determine at 100 mg/l.

Executive summary:

Aim of this study was to assess the short term toxicity of test chemical to aquatic algae and cyanobacteria. Study was performed according to the OECD Guideline 201 (Alga, Growth Inhibition Test) in a static system for the total exposure period of 72 hrs. The solution of white pearl 100 mg/l was prepared by dissolving the substance in OECD growth medium. Test conducted at limit concentration of 100 mg/l. Strain 86.81 SAG were used in the study. 5x10(3) cells/ml were added in 100 ml test vessel. 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, inhibitory concentration IC was calculated. The differences in means of control and sample were estimated by the t-test for independent groups at a 95 % confidence level, all individual replicates were used (STATISTICA CZ – data analysis software system, version 9.0, StatSoft, Inc.). Statistically significant differences are for p < 0.05. After the exposure of chemical with algae Desmodesmus subspicatus, no inhibition were observed. And the IC0% was determine at 100 mg/l. As no effect were observed at limit dose 100 mg/l thus it was concluded that the EC50 was > 100 mg/. Based on the no effect on the growth of algae, it was concluded that the chemical was nontoxic and not classified as per the CLP classification criteria.

 

Description of key information

Aim of this study was to assess the short term toxicity of test chemical to aquatic algae and cyanobacteria. Study was performed according to the OECD Guideline 201 (Alga, Growth Inhibition Test) in a static system for the total exposure period of 72 hrs. The solution of white pearl 100 mg/l was prepared by dissolving the substance in OECD growth medium. Test conducted at limit concentration of 100 mg/l. Strain 86.81 SAG were used in the study. 5x10(3) cells/ml were added in 100 ml test vessel. 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, inhibitory concentration IC was calculated. The differences in means of control and sample were estimated by the t-test for independent groups at a 95 % confidence level, all individual replicates were used (STATISTICA CZ – data analysis software system, version 9.0, StatSoft, Inc.). Statistically significant differences are for p < 0.05. After the exposure of chemical with algae Desmodesmus subspicatus, no inhibition were observed. And the IC0% was determine at 100 mg/l. As no effect were observed at limit dose 100 mg/l thus it was concluded that the EC50 was > 100 mg/. Based on the no effect on the growth of algae, it was concluded that the chemical was nontoxic and not classified as per the CLP classification criteria.

Key value for chemical safety assessment

EC10 or NOEC for freshwater algae:

100 mg/L

Additional information

Aim of this study was to assess the short term toxicity of test chemical to aquatic algae and cyanobacteria. Study was performed according to the OECD Guideline 201 (Alga, Growth Inhibition Test) in a static system for the total exposure period of 72 hrs. The solution of white pearl 100 mg/l was prepared by dissolving the substance in OECD growth medium. Test conducted at limit concentration of 100 mg/l. Strain 86.81 SAG were used in the study. 5x10(3) cells/ml were added in 100 ml test vessel. 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, inhibitory concentration IC was calculated. The differences in means of control and sample were estimated by the t-test for independent groups at a 95 % confidence level, all individual replicates were used (STATISTICA CZ – data analysis software system, version 9.0, StatSoft, Inc.). Statistically significant differences are for p < 0.05. After the exposure of chemical with algae Desmodesmus subspicatus, no inhibition were observed. And the IC0% was determine at 100 mg/l. As no effect were observed at limit dose 100 mg/l thus it was concluded that the EC50 was > 100 mg/. Based on the no effect on the growth of algae, it was concluded that the chemical was nontoxic and not classified as per the CLP classification criteria.