Benzenesulfonic acid, 2,2'-(1,2-ethenediyl)bis[5-nitro-, reaction products with 4-[(4-aminophenyl)azo]benzenesulfonic acid, reduced, oxidized, potassium sodium salts

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

Study period:

1991

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1991

Report date:

1991

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Benzenesulfonic acid, 2,2'-(1,2-ethenediyl)bis[5-nitro-, disodium salt, reaction products with 4-[(4-aminophenyl)azo]benzenesulfonic acid, sodium salts

EC Number:

215-397-8

EC Name:

Benzenesulfonic acid, 2,2'-(1,2-ethenediyl)bis[5-nitro-, disodium salt, reaction products with 4-[(4-aminophenyl)azo]benzenesulfonic acid, sodium salts

Cas Number:

1325-54-8

Molecular formula:

Molecular formula of the main constituents: (1) C38H24N8Na4O12S4 (2) C52H32N10Na6O18S6

IUPAC Name:

Reaction mass of Tetrasodium 5-[[4-[(4-sulfonatophenyl)diazenyl]phenyl]diazenyl]-2-[2-[2-sulfonato-4-[[4-[(4-sulfonatophenyl)diazenyl]phenyl]diazenyl]phenyl]ethenyl]benzenesulfonate and Hexasodium 2-((E)-2-sulfonato-4-((E)-(3-sulfonato-4-((E)-2-sulfonato-4-((E)-(4-((E)-(4-sulfonatophenyl)diazenyl)phenyl)diazenyl)styryl)phenyl)diazenyl)styryl)-5-((E)-(4-((E)-(4- sulfona-tophenyl)diazenyl)phenyl)diazenyl)benzenesulfonate.

Test material form:

solid: particulate/powder

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: all

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- test solutions prepared according to the OECD GUideline No. 201 with the following final concentrations: 62.3, 250 and 1000 mg/L and the control sample.

Test organisms

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Scenedesmus subspicatus CHODAT
- Common name: unicellular green algal species.
- Strain: No. 8681 SAG
- Source (laboratory, culture collection):Sammlung von Algenkulturen, Pflanzenphysiologisches Institut der Universität, D-3400 Göttingen, F.R:G.
- Age of inoculum (at test initiation): The algae were grown in the laboratories of RCC
- Method of cultivation: Under standardized conditions according to the OECD Guideline No 201.

ACCLIMATION
- Acclimation period: 72h
- Culturing media and conditions (same as test or not):10000 cells per ml test solution were taken from a sterile pre-culture, at the same conditions as in the test.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Test conditions

Test temperature:

21.0 - 23.4°C

pH:

7.8 - 10.3

Nominal and measured concentrations:

The nominal concentrations tested were 62.3, 125, 250, 500 and 1000 mg test substance/L and a control without any additions.

Details on test conditions:

TEST SYSTEM
- Test vessel: 250 ml Erlenmeyer flasks stopped with permaeble plugs.
- Test solutions were incubated on a laboratory shaker in an air-conditioned room
- Initial cells density: 10.000 cells/mL
- No. of vessels per concentration (replicates): 2



GROWTH MEDIUM
- Standard medium used: yes


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: According to OECD guideline 201


OTHER TEST CONDITIONS
- Adjustment of pH: 7.8 at the begining of the test
- Photoperiod: continuous illumination
- Light intensity and quality: 8000 lux (±20%)


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: measured according to guidelin


TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

72 h

Dose descriptor:

EC0

Effect conc.:

ca. 62.3 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 2

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 3

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

27.4 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Effect concentrations 4

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

344.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Any other information on results incl. tables

Influence of the test substance on algae growth (cells x 103/ml) during the test duration of 96 hours.

Concentration	24h rep./mean	48h /mean	72h /mean	96h/mean
Control	42.6	260.8	1178.7	3013.0
62.3 mg/l	36.0	198.9	1032.6	2322.4
125.0 mg/l	33.3	155.6	778.1	1598.0
250.0 mg/l	28.7	145.3	660.3	1501.3
500.0 mg/l	26.6	120.1	552.6	1564.7
1000 mg/l	23.7	91.4	322.6	1041.3

Influence of the test substance on algae growth (Growth Rate μ and Percentage Inhibition of μ)

Nominal test subst. concentration	μ (0 -72h)	Iμ (0 -72h)	μ (0 -96h)	Iμ (0 -96h)
Control	1.590	--	1.428	--
62.3 mg/l	1.547	2.7	1.363	4.6
125.0 mg/l	1.453	8.6	1.270	11.0
250.0 mg/l	1.397	12.2	1.253	12.3
500.0 mg/l	1.337	15.9	1.265	11.4
1000.0 mg/l	1.160	27.0	1.163	18.6

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The 72-h ErC0 was determined at ca. 62 mg/L. The ErC50 is >1000 mg/L. The substance is not acutely or chronically harmful to freshwater green algae.

Executive summary:

The purpose of this test was to determine the effects of the test substance on the growth of a unicellular green algal species (Scenedesmus subspicatus) over several generations. The influence of test sample on the growth of the green alga Scenedesmus subspicatus Chodat was investigated in a 96-hour static test according to the OECD Guideline No. 201, adopted June 7, 1984 and the Draft ISO/TC 147, submitted June 25, 1987. The test was performed in compliance with the Good Laboratory Practice Regulations. The nominal concentrations tested were 62.3, 125, 250, 500 and 1000 mg test substance/1 and a control without any additions. The test substance has obviously a low inhibition effect on the growth of Scenedesmus subspicatus. At the highest concentration tested the algae biomass was inhibited by about 70 %, the growth rate only by about 19 % at the end of the test. In conclusion the EC50 (72h) > 1000 mg/l.