2-(3,7-dimethylocta-2,6-dienyl)cyclopentan-1-one

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:

April 12-17 2019

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

2-(3,7-dimethylocta-2,6-dienyl)cyclopentan-1-one

EC Number:

268-706-3

EC Name:

2-(3,7-dimethylocta-2,6-dienyl)cyclopentan-1-one

Cas Number:

68133-79-9

Molecular formula:

C15H24O

IUPAC Name:

2-(3,7-dimethylocta-2,6-dienyl)cyclopentan-1-one

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: all
- Sampling method: Samples were taken at test start, 24 hrs, and 48 hrs. 500 uL samples were taken and stabilized with 500 uL acetonitrile.
- Sample storage conditions before analysis: Deep frozen.

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Test substance was added to water to create a stock solution. The stock solution was then diluted to create the appropriate concentration. The solution was ultrasonicated for 5 minutes.
- Eluate:
- Differential loading:
- Controls:
- Chemical name of vehicle (organic solvent, emulsifier or dispersant):
- Concentration of vehicle in test medium (stock solution and final test solution(s) or suspension(s) including control(s)):
- Evidence of undissolved material (e.g. precipitate, surface film, etc.): The stock solution had an oily layer on the surface.
- Other relevant information:

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name:
- Strain/clone: Daphnia magna Straus, Clone V
- Justification for species other than prescribed by test guideline:
- Age at study initiation (mean and range, SD): less than 24 hrs old
- Weight at study initiation (mean and range, SD):
- Length at study initiation (length definition, mean, range and SD):
- Stage and instar at study initiation:
- Valve height at study initiation, for shell deposition study (mean and range, SD):
- Peripheral shell growth removed prior to test initiation:
- Method of breeding:
- Source:
- Age of parental stock (mean and range, SD):
- Feeding during test: No
- Food type:
- Amount:
- Frequency:

ACCLIMATION
- Acclimation period:
- Acclimation conditions (same as test or not):
- Type and amount of food:
- Feeding frequency:
- Health during acclimation (any mortality observed):

QUARANTINE (wild caught)
- Duration:
- Health/mortality:

METHOD FOR PREPARATION AND COLLECTION OF EARLY INSTARS OR OTHER LIFE STAGES, INCLUDING CULTURING CONDITIONS:

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Hardness:

13 degrees dH

Test temperature:

19.4-20.8 degrees C

pH:

7.69-7.98

Dissolved oxygen:

>= 8.4 mg/L

Nominal and measured concentrations:

Nominal: 0. 0.640, 0.160, 0.400, 1.00, 2.50 mg/L
Measured: 0, 0.0272, 0.806, 0.155, 0.449, 1.26 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 mL glass beakers
- Type (delete if not applicable): covered with glass plates
- Material, size, headspace, fill volume: glass, 100 mL
- Volume of solution: 50 mL
- Aeration: No
- Type of flow-through (e.g. peristaltic or proportional diluter):
- Renewal rate of test solution (frequency/flow rate):
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- No. of vessels per vehicle control (replicates):
- Biomass loading rate:

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Elendt M4 test medium
- Total organic carbon:
- Particulate matter:
- Metals:
- Pesticides:
- Chlorine:
- Alkalinity:
- Ca/mg ratio:
- Conductivity:
- Salinity:
- Culture medium different from test medium:
- Intervals of water quality measurement:

OTHER TEST CONDITIONS
- Adjustment of pH:
- Photoperiod: 16 hrs light/ 8 hrs dark
- Light intensity:

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): immobilisation at 24 and 48 hrs

VEHICLE CONTROL PERFORMED: yes/no

RANGE-FINDING STUDY
- Test concentrations:
- Results used to determine the conditions for the definitive study:

Reference substance (positive control):

yes

Remarks:

Potassium dichromate at concentrations of 0.60 and 2.10 mg/L

Results and discussion

Effect concentrations

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

0.677 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Behavioural abnormalities: At the 24 hr observation, the mobile daphnids appeared sluggish. At the 48 hr observation, half of the daphnids were swimming on the surface at the 1.00 mg/L concentration.
- Observations on body length and weight:
- Other biological observations:
- Mortality of control: None
- Other adverse effects control:
- Immobilisation of control: None
- Abnormal responses:
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values:
- Effect concentrations exceeding solubility of substance in test medium:

Results with reference substance (positive control):

- Results with reference substance valid? Yes
- Relevant effect levels: 100% of the daphnids were immobilised at 2.10 mg/L by the 24 hr observations. No animals were immobilised at the 0.60 mg/L concentration. The EC50 is therefore between 0.60 and 2.10 mg/L.
- Limit test: No
- Dose-response test: Yes
- ECx: EC50 0.60-2.10 mg/L
- Other:

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The 48-hr EC50 in daphnids is 0.677 mg/L (measured).

Executive summary:

The toxicity of Apritone to aquatic invertebrates was tested in an OECD guideline 202 study. 20 daphnids were exposed to concentrations of 0, 0.0272, 0.806, 0.155, 0.449, and 1.26 mg/L (measured) for 48 hrs. The reference substance potassium dichromate was also tested. Results with negative and positive controls were valid. The 48 -hr EC50 based on immobilisation was 0.677 mg/L (measured).