Custom Yellow #2

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

10-mar-2009 to 19-mar-2009

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study has been performed according to OECD and/or EC guidelines and according to GLP principles.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2009

Report date:

2010

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

ISO 6341 (Water quality - Determination of the Inhibition of the Mobility of Daphnia magna Straus (Cladocera, Crustacea))

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

Test guideline 4

Qualifier:

according to guideline

Guideline:

other: Guidance document on aquatic toxicity testing of difficult substances and mixtures, OECD series on testing and assessment number 23, December 14, 2000

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Reference

Name:

Unnamed

Type:

Constituent

Details on test material:

- Substance type: Bright yellow powder
- Physical state: Solid
- Stability under test conditions: Unknown
- Storage condition of test material: At room temperature in the dark

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: all test concentrations and the control
- Sampling method:
Frequency at t=0 h and t=48 h
Volume 1 ml from the approximate centre of the test vessels
- Sample storage conditions before analysis: Samples were stored in a freezer until analysis

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Preparation of test solutions started with a loading rate of 100 mg/l applying 1 day of magnetic stirring to reach maximum solubility of the test substance in the test medium. The resulting aqueous mixture was filtered through a membrane filter (Whatman, 0.45 µm) where after the filtrate was used as the highest test concentration. Lower test concentrations were prepared by subsequent dilutions of the filtrate in test medium. The final test solutions were all clear and colourless.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Source: In-house laboratory culture
- Age at study initiation (mean and range, SD): < 24 hours
- Method of breeding: With newborn daphnids, i.e. less than 3 days old, by placing about 250 of them into 5 litres of medium in an all-glass culture vessel
- Feeding during test: No

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

None.

Test conditions

Hardness:

180 mg/l expressed as CaCO3

Test temperature:

20.0 - 20.9 °C

pH:

At t=0 h: 7.9
At t=48 h: 8.0 - 8.1

Dissolved oxygen:

At t=0 h: 8.8 - 9.2
At t=48 h: 9.0

Salinity:

Not applicable.

Nominal and measured concentrations:

Nominal concentrations; 0.10, 1.0, 10 and 100% of a filtered solution prepared at a loading rate of 100 mg/l
Measured concentrations:
Analytical results showed that the actual test concentrations were below the limit of quantification, i.e. below 0.05 mg/l, from the start of the test. Therefore, these results indicated that medium solubility was below 0.05 mg/l. Analysis of the filter residue showed that Custom Yellow #2 was used for the preparation of test concentrations.

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 ml, all glass
- Type (delete if not applicable): open - ~80 ml, normal headspace
- Aeration: no
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4 for the highest concentration, 2 in the lower test concentrations
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Adjusted ISO medium
- Culture medium different from test medium: yes, for culturing M7 medium is used


OTHER TEST CONDITIONS
- Photoperiod: 16 hours photoperiod daily


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : EC50 daily

Reference substance (positive control):

yes

Remarks:

potassium dichromate (K2Cr2O7)

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 0.05 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: EC50 > water solubility

Effect concentrations 2

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

0.05 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: NOEC = water solubility

Details on results:

- Behavioural abnormalities: no
- Mortality of control: no
- Other adverse effects control: not observed

Results with reference substance (positive control):

- Results with reference substance valid? yes
- EC50/LC50:
The 24h-EC50 was 0.55 mg/l with a 95% confidence interval between 0.50 and 0.63 mg/l.

The 48h-EC50 was 0.30 mg/l with a 95% confidence interval between 0.25 and 0.35 mg/l.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Due to the very low solubility of Custom Yellow #2 in test medium, concentration levels that might be toxic for daphnids could not be reached.

The 48h-EC50 was above 0.05 mg/l, which was the limit of quantification. The NOEC was 0.05 mg/l.

In conclusion: Custom Yellow #2 is not considered to be ecotoxic based on the maximum soluble concentration and the absence of effects at this concentration.