2-Naphthalenesulfonic acid, 7-amino-4-hydroxy-8-[2-[2-sulfo-4-[[2-(sulfooxy)ethyl]sulfonyl]phenyl]diazenyl]-, potassium sodium salt (1:?:?), coupled with diazotized 2-[(4-amino-5-methoxy-2-methylphenyl)sulfonyl]ethyl hydrogen sulfate

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Study initiation date - 12 May 2003; Experiment start date - 13 May 2003; Experiment end date - 21 June 2003; Study completion date - 16 July 2003.

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Identity: FAT 40812/A
Batch: WP 8/03
Purity: approx. 75 %
Appearance: Solid, dark red-brownish powder
Expiration date: 23 April 2010
Storage: At room temperature at about 20 °C

Analytical monitoring:

yes

Details on sampling:

Samples of aqueous solutions of the blank and the highest test concentration were taken from the test solutions at the start and at the end of the exposure period. All test medium samples for the analytical determinations were taken from the approximate center of the test vessels and kept at -18 °C to -25 °C until analysis.

Vehicle:

no

Details on test solutions:

Stock solution:
100.0 mg test item were mixed with test medium and then made up to 1000 mL with test medium in a volumetric flask. The appearance of the solution was red.

Test concentrations:
A range finding test was performed with concentrations of 0.01, 0.1, 1.0, 10 and 100mg/L. based on the pre-test, the main test was performed with nominal test item concentrations of 4.3, 9.4, 21, 45, and 100 mg/L and a blank control without test item. Calculated amounts of the stock solution to produce the desired test concentrations were given into the test vessels and then made up to 200 mL with test medium. The 200 mL of test solutions were divided up into portions of 100 mL for each replicate test vessel.

Test organisms (species):

Daphnia magna

Details on test organisms:

- Test species: Daphnia magna Straus, clone 5
- Breeding: Cultures of Daphnia magna were bred in the laboratories of the test facility in glass vessels containing approximately 3 litre of reconstituted water (M4 medium, Elendt 1990). The water was renewed partially twice a week. The Daphnia were fed daily with the exception of the weekend with a suspension of green algae (Scenedesmus obliquus) in such quantities that the food was consumed within 24 hours. Culturing was performed at 18 to 22 °C and a photoperiod of 16 hours light and 8 hours dark. Twice a week the young Daphnia were separated from the parent animals to maintain a stock of reproducing Daphnia within the same age.
- Quality control: The quality of the Daphnia is checked at least every 3 months by determining the EC50 value (24 h) for the reference item potassium dichromate. Reference control on April 02, 2003: EC50 =1.1 mg/L. The EC50 for potassium dichromate after 24 hours of exposure was determined among 46 laboratories in an international ring-test with Daphnia magna and found to be at 1.5 mg/L (0.9 to 1.9 mg/L). Therefore, the cultures of Daphnia magna used by the test facility were demonstrated to be adequately sensitive.
- Pre-treatment: About 24 hours before the start of exposure reproductive Daphnia were separated from the young Daphnia by sieving all individuals through a 1000 µm sieve. This procedure was repeated before the start of the exposure, to receive young Daphnia with an age of less than 24 hours.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

214 mg/L CaC03

Test temperature:

19.9 - 20.4 °C

pH:

7.6 to 8.0

Dissolved oxygen:

The oxygen content was in the range of 96 - 98 %.

Nominal and measured concentrations:

- Nominal concentrations: 4.3, 9.4, 21, 45, and 100 mg/L.
- Measured concentrations: 105 % and 107 % of nominal at the start and end of exposure, respectively.

Details on test conditions:

- Light: 16 hours light daily, 8 hours dark
- Test vessels: 250 mL beakers containing 100 mL test medium
- Daphnia per concentration: 20, two beakers per test concentration with 10 animals each.
- Stock solution: 100.0 mg test item were mixed with test medium and then made up to 1000 mL with test medium in a volumetric flask. The appearance of the solution was red.
- Test concentrations: Calculated amounts of the stock solution to produce the desired test concentrations were given into the test vessels and then made up to 200 mL with test medium. The 200 mL of test solutions were divided up into portions of 100 mL for each replicate test vessel.

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

No immobilisation of Daphnia was observed in the control and at any of the test item concentrations after 24 hours. After 48 hours of exposure, no immobilisation was observed at any of the treatments.

Results with reference substance (positive control):

EC50 = 1.5 mg/L

Reported statistics and error estimates:

No statistical analysis of the data was performed.

Validity criteria fulfilled:

yes

Conclusions:

The 48-h EC50 value is >100 mg/L in Daphnia magna.

Executive summary:

In a GLP compliant study, performed according to OECD Guideline 202, the acute toxicity of the test substance to 20 Daphnia magna was determined in a 48-hours static test. The nominal concentration were 4.3, 9.4, 21, 45, and 100 mg/L. The measured test concentrations in the analysed samples of 100 mg/L were 105% of the nominal values at the start and 107 % at the end of exposure. Therefore, under test conditions the test article was sufficiently stable. No immobilisation of Daphnia was observed in the control and at any of the test item concentrations after 24 hours. After 48 hours of exposure, no immobilisation was observed at any of the treatments. Therefore, the EC50 was determined to be >100mg/L.

Description of key information

In a GLP-compliant study, performed according to OECD Guideline 202, the acute toxicity of the test substance to 20 Daphnia magna was determined in a 48-hours static test. The nominal concentration were 4.3, 9.4, 21, 45, and 100 mg/L. The measured test concentrations in the analysed samples of 100 mg/L were 105 % of the nominal values at the start and 107 % at the end of exposure. Therefore, under test conditions the test article was sufficiently stable. No immobilisation of Daphnia was observed in the control and at any of the test item concentrations after 24 hours. After 48 hours of exposure, no immobilisation was observed at any of the treatments. Therefore, the EC50 was determined to be >100 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L