Benzenesulfonic acid, 2-[2-[5-(aminocarbonyl)-1-ethyl-1,6-dihydro-2-hydroxy-4-methyl-6-oxo-3-pyridinyl]diazenyl]-4-[[4-chloro-6-[[4-[[2-(sulfooxy)ethyl]sulfonyl]phenyl]amino]-1,3,5-triazin-2-yl]amino]-, sodium salt (1:2)

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

other company data

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

Test guideline 3

Qualifier:

according to guideline

Guideline:

ISO 8692 (Water Quality - Fresh Water Algal Growth Inhibition Test with Scenedesmus subspicatus and Selenastrum capricornutum)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

412-720-6

EC Name:

-

Cas Number:

156653-67-7

Molecular formula:

C26H26ClN9O12S3.2 Na

IUPAC Name:

disodium 2-[2-(5-carbamoyl-1-ethyl-2-hydroxy-4-methyl-6-oxo-1,6-dihydropyridin-3-yl)diazen-1-yl]-4-{[4-chloro-6-({4-[2-(sulfonatooxy)ethanesulfonyl]phenyl}amino)-1,3,5-triazin-2-yl]amino}benzene-1-sulfonate

Test solutions

Vehicle:

yes

Details on test solutions:

Preparation of test solutions started with a loading rate of 100 mg/l applying a short period of vigorous shaking to accelerate the dissolving of the test substance in the test medium. The lower test concentrations were prepared by subsequent dilutions of the 100 mg/l concentration in test medium. The final test solutions were clear and increasingly yellow.
After prepareation, volumes of 50 ml were added to each replicate of the respective test concentration. Subsequently, 1 ml of an algal suspension was added to each replicate providing a cell density of 1.0x 10E4 cells/ml.

Test organisms

Test organisms (species):

other: Pseudokirchneriella subcapitata, strain: NIVA CHL1

Details on test organisms:

TEST ORGANISM
- Common name: Pseudokirchneriella subcapitata
- Strain: NIVA CHL1
- Method of cultivation:Algae stock cultures were started by inoculating growth medium with algal cells from a pure culture on agar. The suspensions were continuously aerated and exposed to light in a climate room at a temperature of 21-24℃.
ACCLIMATION
- Acclimation period: 3 days before the start of the test, cells from the algal stock culture were inoculated in culture medium at a cell density of 1.0 x 10E4 cells/ml. The pre-culture was maintained under the same conditions as used in the test. The cell density was measured immediately before use.

- Source (laboratory, culture collection):In-house laboratory culture

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Post exposure observation period:

at t=0 h, t=24 h and t=72 h

Test conditions

Hardness:

24 mg CaCO3/l

Test temperature:

21-24℃

pH:

8.1 ± 0.2

Nominal and measured concentrations:

1.0, 3.2, 10, 32 and 100 mg/l

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 81 mg/L

Nominal / measured:

nominal

Basis for effect:

growth rate

Effect concentrations 2

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

22 mg/L

Nominal / measured:

nominal

Basis for effect:

other: yield inhibition

Remarks on result:

other: 9.6 to 49 mg/l

Results with reference substance (positive control):

Potassium dichromate reduced growth rate of this fresh water algae species at nominal concentrations of 0.56 mg/l and higher.

The EC50 for growth rate reduction (ErC50: 0-72h) was 1.1 mg/l with a 95% confidence interval ranging from 1.0 to 1.3 mg/l. The historical ranges for growth rate reduction lie between 0.82 and 2.3 mg/l. Hence, the ErC50: 0-72h for the persent batch corresponds with this range.

The EC50 for yield inhibition (EyC50: 0-72h) was 0.59 mg/l with a 95% confidence interval ranging from 0.51 to 0.68 mg/l. The historical ranges of the 72h EC50 for yield inhibition lie between 0.43 and 1.1 mg/l. Hence, the EyC50: 0-72h for the present batch corresponds with this range.

Any other information on results incl. tables

Table Effect parameters

Parameter	Concentration Everzol SR37 (mg/l)
NOERC	2.3
72h-ERC50	>81
NOEYC	2.3
72h-EYC50	22