1-Naphthalenesulfonic acid, 3-diazo-3,4-dihydro-4-oxo-, ester with phenyl(2,3,4-trihydroxyphenyl)methanone 6-diazo-5,6-dihydro-5-oxo-1-naphthalenesulfonate

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:

April 19, 2020 to May 04, 2020

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

2004

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 0 and 100 mg/L
- Sampling method: samples were taken directly after preparation of the test solutions and after 24 h
- Sample storage conditions before analysis: one replicate was directly anaylsed, the other replicate was deep-frozen as backup

Vehicle:

no

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Age at study initiation: less than 24 h
- Source: Merck KGaA
- Feeding during test: no

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Test temperature:

20.8-21.6 °C

pH:

the pH was not adjusted and ranged from 7.8 to 8.0 (measurements of freshly prepared test solutions and after 24 h)

Dissolved oxygen:

8.29-8.66 mg/L

Nominal and measured concentrations:

nominal: 0 and 100 mg/L
measured:

Details on test conditions:

TEST SYSTEM
- Test vessel: 20mL glass tubes
- Type: open
- Volume of solution: 20 mL
- Aeration: no
- Renewal rate of test solution: after 24 h
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 h light, 8 h dark
- Light intensity: 653.5 -663.5 Lux

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 0.05 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mobility

Details on results:

- Behavioural abnormalities: no abnormalities observed

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of the present study, an aqueous solution of nominal 100 mg/L of the test item revealed no aquatic toxicity in the test item. The 48-h EC50 was > LOQ (LOQ > 0.05 mg/L) and, thus, could not be determined in this study.

Executive summary:

The objective of this study was to evaluate the influence of the test item on the mobility of Daphnia magna according to OECD Guideline 202. Juvenile daphnids were exposed to a nominal test item concentration of 100 mg/L (limit test) over 48 hours, in an open static system. The daphnids were observed for immobilization 24 and 48 hours after placing in the aqueous test item solution. The study comprised of one test item group with four test vessels containing five daphnids each, i.e. 20 daphnids in total. Additionally, one control group (20 daphnids) was used. The test item concentration was analysed using HPLC directly after preparing of the test solution and after 24 h. However, the test substance concentration in the test solution could not be detected as it was below the limit of quantification of the chosen method (LOG<0.05 mg/L). As a conclusion, daphnids exposed to an aqueous preparation of a nominal concentration of 100 mg/L of the test item were not affected, EC50(48 h) >0.05 mg/L (measured) and >100 mg/L(nominal). 

Description of key information

Under the conditions of the present study, an aqueous solution of nominal 100 mg/L of the test item revealed no aquatic toxicity in the test item. The concentration of the 100 mg/L preparation could not be analytically determined as it was <LOQ. Thus, a precise LC50 value was not determined.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

> 100 mg/L