2-{(E)-[6-({4-chloro-6-[(4-{[2-(sulfooxy)ethyl]sulfonyl}phenyl)amino]-1,3,5-triazin-2-yl}amino)-1-hydroxy-3-sulfonaphthalen-2-yl]diazenyl}naphthalene-1,5-disulfonic acid

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Remarks:

Experimental data of test chemical

Justification for type of information:

Data for the target chemical is summarized based on the structurally similar read across chemicals

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

other: as mentioned below

Principles of method if other than guideline:

WoE report is based on two study for aquatic algae and cyanobacteria the test chemical :
1.Short term toxicity to algae was performed according to the OECD guideline 201 in a static system.
2.Short term toxicity of test chemical on the growth of algae was studied by following guideline.

GLP compliance:

not specified

Details on test solutions:

1) The stock solution (200 mg/L) was prepared by dissolving brown 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.

2)The stock solution 130 mg/L was prepared by dissolving dark red powder in OECD growth medium. Test solutions of required concentrations were prepared by mixing the stock solution of the test sample with OECD growth medium and inoculum culture.
- Controls: OECD medium as specified in OECD 201, used as a control and for dilution of the stock solution.

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

1 and 2) 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

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test temperature:

1) and 2) 23±2°C

pH:

1) Test at highest concentration: 8 changed to 7.9 during tests
Control: 8.0 (changed to 8.1 during test)

2)The sample at concentration 130 mg/L : pH = 7.8 changed to pH = 7.6 during the test,
Control : pH = 8.0 changed to pH = 7.6 during the test

Nominal and measured concentrations:

1) 0,12.5, 25, 50, 100, 200 mg/l
2)0, 2.6, 5.6, 12.0, 27.0, 59.0 and 130 mg/L

Details on test conditions:

1 and 2) TEST SYSTEM
- Test vessel: 50ml glass vessel
- Type : closed (with air-permeable stopper)
- Material, size, headspace, fill volume: 7.5 ml
- Aeration: No data
- Type of flow-through (e.g. peristaltic or proportional diluter): No data
- Renewal rate of test solution (frequency/flow rate): No data
- Initial cells density: 5x103 cells/mL
- Control end cells density: No data
- No. of organisms per vessel: No data
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): No data
- No. of vessels per vehicle control (replicates): No data

GROWTH MEDIUM
- Standard medium used: Yes

OTHER TEST CONDITIONS
- Adjustment of pH: Without adjustment
- Photoperiod: Continuous
- Light intensity and quality: 6000 lx - 8000 lx

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell counting: Electronic particle counter.
- Chlorophyll measurement: No
- Other: ErC50 was calculated using non-linear regression by the software Prism 4.0

Reference substance (positive control):

yes

Remarks:

Potassium dichromate (K2Cr2O7)

Duration:

72 h

Dose descriptor:

other: ErC50

Effect conc.:

356.2 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95% CL: 266.8 - 475.7

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

265.1 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95% CL: 207.2 – 339.1 mg/L

Results with reference substance (positive control):

Results with reference substance valid
- ErC50: 0.69 mg/L

Reported statistics and error estimates:

ErC50 was calculated using non-linear regression by the software Prism 4.0

Validity criteria fulfilled:

not specified

Conclusions:

The test chemical is not likely to be toxic to aquatic algae and cyanobacteria atleast in the concentration range of 256- 365 mg/l

Executive summary:

Data available for test chemicals has been reviewed to determine the toxicity to aquatic algae and cyanobacteria of the test chemical .The studies are as mentioned below:

1)Freshwater algal growth inhibition test was carried out on Desmodesmus subspicatus with the substance according to OECD Guideline 201. The stock solution (200 mg/L) was prepared by dissolving brown 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. and tested at the concentrations 0, 12.5, 25, 50, 100, 200 mg/L. Effects on the growth rate of the organism were studied.

The median effective concentration (ErC50) for the test substance, in Desmodesmus subspicatus was determined to be 356.2 mg/L. This value indicates that the substance is likely to be non-hazardous to aquatic algae and can not be classified as toxic as per the CLP criteria.

2) Freshwater algal growth inhibition test was carried out on Desmodesmus subspicatus with the substance according to OECD Guideline 201. The test substance was dissolved in OECD growth medium and tested at the concentrations 0, 2.6, 5.6, 12.0, 27.0, 59.0 and 130 mg/L. Effects on the growth rate of the organism were studied. The median effective concentration (ErC50) for the test substance, Disodium 4-hydroxy-3-[(4-sulphonatonaphthyl)azo] naphthalene - sulphonate, in Desmodesmus subspicatus was determined to be 265.1 mg/L. Based on this E_rC50 value and after comparing with CLP criteria for aquatic classification of the substance it is concluded that the test substance does not exhibit toxicity to aquatic algae (Desmodesmus subspicatus).

Thus, based on the above summarised studies, test substance and it’s structurally and functionally similar read across substance, it can be concluded that effect concetration value is greater than 365 mg/L. Thus, comparing this value with the criteria of CLP regulation,test material cannot be classified for toxicity of aquatic aquatic algae and cyanobacteria .Hence,based on the data available for the structurally and functionally similar read across, test chemical is not likely to be toxic atleast in the concentration range of 256 -365 mg/L .

Description of key information

Toxicity to aquatic algae and cyanobacteria:

Data available for test chemicals has been reviewed to determine the toxicity to aquatic algae and cyanobacteria of the test chemical .The studies are as mentioned below:

1)Freshwater algal growth inhibition test was carried out on Desmodesmus subspicatus with the substance according to OECD Guideline 201. The stock solution (200 mg/L) was prepared by dissolving brown 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. and tested at the concentrations 0, 12.5, 25, 50, 100, 200 mg/L. Effects on the growth rate of the organism were studied.

The median effective concentration (ErC50) for the test substance, in Desmodesmus subspicatus was determined to be 356.2 mg/L. This value indicates that the substance is likely to be non-hazardous to aquatic algae and can not be classified as toxic as per the CLP criteria.

2) Freshwater algal growth inhibition test was carried out on Desmodesmus subspicatus with the substance according to OECD Guideline 201. The test substance was dissolved in OECD growth medium and tested at the concentrations 0, 2.6, 5.6, 12.0, 27.0, 59.0 and 130 mg/L. Effects on the growth rate of the organism were studied. The median effective concentration (ErC50) for the test substance, Disodium 4-hydroxy-3-[(4-sulphonatonaphthyl)azo] naphthalene - sulphonate, in Desmodesmus subspicatus was determined to be 265.1 mg/L. Based on this E_rC50 value and after comparing with CLP criteria for aquatic classification of the substance it is concluded that the test substance does not exhibit toxicity to aquatic algae (Desmodesmus subspicatus).

Thus, based on the above summarised studies, test substance and it’s structurally and functionally similar read across substance, it can be concluded that effect concetration value is greater than 365 mg/L. Thus, comparing this value with the criteria of CLP regulation,test material cannot be classified for toxicity of aquatic aquatic algae and cyanobacteria .Hence,based on the data available for the structurally and functionally similar read across, test chemical is not likely to be toxic atleast in the concentration range of 256 -365 mg/L .

Additional information

Toxicity to aquatic algae and cyanobacteria:

Data available for test chemicals has been reviewed to determine the toxicity to aquatic algae and cyanobacteria of the test chemical .The studies are as mentioned below:

1)Freshwater algal growth inhibition test was carried out on Desmodesmus subspicatus with the substance according to OECD Guideline 201. The stock solution (200 mg/L) was prepared by dissolving brown 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. and tested at the concentrations 0, 12.5, 25, 50, 100, 200 mg/L. Effects on the growth rate of the organism were studied.

The median effective concentration (ErC50) for the test substance, in Desmodesmus subspicatus was determined to be 356.2 mg/L. This value indicates that the substance is likely to be non-hazardous to aquatic algae and can not be classified as toxic as per the CLP criteria.

2) Freshwater algal growth inhibition test was carried out on Desmodesmus subspicatus with the substance according to OECD Guideline 201. The test substance was dissolved in OECD growth medium and tested at the concentrations 0, 2.6, 5.6, 12.0, 27.0, 59.0 and 130 mg/L. Effects on the growth rate of the organism were studied. The median effective concentration (ErC50) for the test substance, Disodium 4-hydroxy-3-[(4-sulphonatonaphthyl)azo] naphthalene - sulphonate, in Desmodesmus subspicatus was determined to be 265.1 mg/L. Based on this E_rC50 value and after comparing with CLP criteria for aquatic classification of the substance it is concluded that the test substance does not exhibit toxicity to aquatic algae (Desmodesmus subspicatus).

Thus, based on the above summarised studies, test substance and it’s structurally and functionally similar read across substance, it can be concluded that effect concetration value is greater than 365 mg/L. Thus, comparing this value with the criteria of CLP regulation,test material cannot be classified for toxicity of aquatic aquatic algae and cyanobacteria .Hence,based on the data available for the structurally and functionally similar read across, test chemical is not likely to be toxic atleast in the concentration range of 256 -365 mg/L .