1-Propanone, 2-hydroxy-2-methyl-, 1-(4-C10-13-alkylphenyl) derivs.

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:

24 June - 15 August, 2008

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:

2008

Report date:

2008

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:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

Test guideline 3

Qualifier:

equivalent or similar to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

1-Propanone, 2-hydroxy-2-methyl-, 1-(4-C10-13-alkylphenyl) derivs.

Cas Number:

1001416-18-7

Molecular formula:

Not applicable - UVCB

IUPAC Name:

1-Propanone, 2-hydroxy-2-methyl-, 1-(4-C10-13-alkylphenyl) derivs.

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 0, 10, 18, 32, 56 and 100 % of a filtered solution prepared at a loading rate of 100 mg/l.
- Sampling method: 2 ml from the approximate centre of the test vessels
- Sample storage conditions before analysis: freezer

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
Preparation of test solutions for the combined limit/range-finding test (0.1, 1.0 and 10 % of the filtrate) started with a loading rate of 100 mg/l. A 15-minute period with ultrasonic waves was followed by 16 minutes of magnetic stirring before a stabilisation period of 1 hour. A clear and colourless solution with a floating layer was obtained. The apparent water soluble fraction of the solution was then siphoned off over glass wool before use as highest test concentration.
For the two main studies a highest test concentration was prepared at a loading rate of 100 mg/l, magnetically stirred for 1 hour and subsequently stabilised for 1 hour. The resulting solution was clear and colourless (1st test) or slightly hazy (2nd test) with a floating layer. The water soluble fraction was collected and filtered through a glass filter (Schleicher and Schuell; GF92) in the 1st test or through glass wool in the 2nd test. The lower test concentrations for both tests (10, 18, 32, 56 and 100 % of a filtered solution) were prepared by subsequent dilution of the filtrate in test medium. All final test solutions were clear and colourless. Note that formulation of the test solutions was performed under dimmed light conditions and that the test vessels were pre-incubated with the respective solutions one day prior to the start of the experiments.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Source: In-house laboratory culture with a known history.
- 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 feeding

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

No post exposure observations.

Test conditions

Hardness:

180 mg/l expressed as CaCO3

Test temperature:

19.4 - 20.0 °C

pH:

7.8 - 7.9

Dissolved oxygen:

8.9 - 9.1 mg/l

Nominal and measured concentrations:

First main test (filtration through glass filter):
100 % filtrate (100 mg/l): 0.15 mg/l (t=0) - 0.10 mg/l (t=48h) -> Mean 0.12 mg/l
56 % filtrate: 0.11 mg/l (t=0) - 0.09 mg/l (t=48h)
32 % filtrate: 0.05 mg/l (t=0) - 0.07 mg/l (t=48h)
18 % filtrate: 0.01 mg/l (t=0) - 0.05 mg/l (t=48h)
10 % filtrate: 0.01 mg/l (t=0) - 0.02 mg/l (t=48h)
Measured concentrations for the 10, 18 and 32% filtrates are indicative as they were obtained by extrapolation of the calibration curve.

Second main test (filtration through glass wool):
100% filtrate (100 mg/l): 0.12 mg/l (t=0) - 0.08 mg/l (t=48h) -> Mean 0.10 mg/l
56 % filtrate: 0.07 mg/l (t=0) - 0.03 mg/l (t=48h)
32 % filtrate: not measured
18 % filtrate: not measured
10 % filtrate: not measured

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 ml, all-glass. Pre-incubated for one day with test solutions.
- Aeration: No aeration of the test solutions
- No. of organisms per vessel: 5 per vessel containing 80 ml of test solution
- No. of vessels per concentration (replicates): 4
- 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
- Adjustment of pH: 7.7
- Photoperiod: 16 hours daily

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

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 10 in combined limit/range-finding study and 1.75 in full tests.
- Range finding study: study was a combined limit/range finding test
- Test concentrations: 0, 0.1, 1.0, 10 and 100 % of a filtered solution at 100 mg/l in the combined limit/range-finding test and 0, 10, 18, 32, 56 and 100 % of a filtered solution at 100 mg/l in two full tests.

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

loading rate

Basis for effect:

mobility

Effect concentrations 2

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 0.1 - 0.12 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

No significant immobility was observed in any of the test groups.

Results with reference substance (positive control):

- Results with reference substance valid: Yes
- Immobility after 48h: 0 % at 0.10 mg/l; 0 % at 0.18 mg/l; 5 % at 0.32 mg/l; 15 % at 0.56 mg/l; 100 % at 1.0 and 1.8 mg/l
- EC50/LC50: 48h-EC50 was 0.62 mg/l with a 95 % confidence interval between 0.53 and 0.77 mg/l.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of the present study with Daphnia magna exposed to the substance no significant acute immobilisation of Daphnia magna was observed up to the limit of solubility in test medium. The 48h-EC50 exceeded the water soluble fraction of the substance obtained after glass or glass-wool filtration of a loading rate prepared at 100 mg/l, with an average measured concentration of 0.1 mg/l.

Executive summary:

The toxicity of the substance to daphnia magna was determined according to OECD Guideline 202. A static test design was used. The daphnids were exposed to a water accomodated fractions of the test substance for 48 hours. Under the conditions of the study with Daphnia magna exposed to the substance no significant acute immobilisation of Daphnia magna was observed up to the limit of solubility in test medium. The 48h-EC50 exceeded the water soluble fraction of the substance obtained after glass or glass-wool filtration of a loading rate prepared at 100 mg/l, with an average measured concentration of 0.1 mg/l.