Methyl 3-oxo-2-pentylcyclopentaneacetate

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:

From 04 August to 23 October 1998

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: OECD Guideline study performed according to GLP but without the analysis of the test solution.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1998

Report date:

1998

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Methyl 3-oxo-2-pentylcyclopentaneacetate

EC Number:

246-495-9

EC Name:

Methyl 3-oxo-2-pentylcyclopentaneacetate

Cas Number:

24851-98-7

Molecular formula:

C13H22O3

IUPAC Name:

methyl 3-oxo-2-pentylcyclopentaneacetate

Details on test material:

- Name of test material (as cited in study report): Methyl dihydrojasmonate
- Substance type: pure active substance
- Physical state: clear colorless liquid
- Analytical purity: >99.98 % (sum of 2 isomers and of few position isomers)
- Stability under test conditions: stable
- Storage condition of test material: room temperature in the dark
- Other: test material is moderately soluble (water solubility > 500 mg/l @ 20°C), has a low Vapour pressure (< 0.0001 Pa) and a logPow < 3

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
Not applicable

Sampling and analysis

Analytical monitoring:

no

Details on sampling:

Not applicable

Test solutions

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
Correctly weighed 200 mg of the test substance and 200 mg of the carrier solvent (HCO-40) were mixed. The mixture was dissolved into and filled up to 200 ml with the test medium in order to prepare a stock solution containing the test substance at the concentration of 1000 mg/l. At the same time, another stock solution containing only the solvent (HCO-40, 1000 mg/L) was prepared in the same manner.
100 ml of fresh test medium was poured into each test flask, and from which estimated adding volume of the stock solution containing the test substance and the stock solutions containing only the solvent was removed. Then the specific volumes of stock solution containing the test substance were added into each test flask geometrically in order to prepare test solutions at the respective concentrations (0 to 30 mg/l). At the same time, the amount of solvent was adjusted such that equal concentrations of solvent where present in each test solution (60 mg/l). For preparing the Control, a fresh test medium was used. And, for preparing the Solvent control (concentration of the solvent: 60 mg/L), the test medium containing only the solvent was used.
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): HCO-40
- Concentration of vehicle in test medium (stock solution and final test solution(s) including control(s)): Stock solution: 1000 mg/l, final test solutions: 60 mg/l
- Evidence of undissolved material (e.g. precipitate, surface film, etc): none

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia
- Strain: Magna
- Source: National Environment Lab - Japan
- Age at study initiation (mean and range, SD): less than 24 hours old
- Method of breeding: 100 ml glassbeakers, no aeration
- 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:

Not Applicable

Test conditions

Hardness:

96 mg/l (CaCO3)

Test temperature:

20.4 - 20.8 °C (within appropriate range)

pH:

7.6 - 8.0 (within appropriate range)

Dissolved oxygen:

7.9 - 8.5 mg/l (within appropriate range)

Salinity:

Not relevant/Not applicable

Nominal and measured concentrations:

0, solvent control, 0.5, 1.0, 2.0, 3.8, 7.6, 15.0 and 30.0 mg/l

Details on test conditions:

TEST SYSTEM
- Test vessel: glass beakers
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: 100 ml test volume
- Aeration: none
- 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): 4
- Biomass loading rate:

TEST MEDIUM / WATER PARAMETERS: prepared/carried out according to OECD TG 202 recommendations

OTHER TEST CONDITIONS
- Adjustment of pH: none
- Photoperiod: 16h light / 8h dark

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : immobilization

TEST CONCENTRATIONS
- Spacing factor for test concentrations: ca. 2
- Justification for using less concentrations than requested by guideline: Not Applicable
- Range finding study: yes (on 10 daphnia for each condition tested):
Pre-test 1: tested concentration and % immobilization after 48h: 1.0 mg/l (0%), 10.0 mg/l (100%), 100 (100%)
Pre-test 2: tested concentration and % immobilization after 24h & 48h: 3.0 mg/l (30% and 40%), 10.0 mg/l (60% and 90%), 30.0 mg/l (70% and 100%), 50.0 mg/l (100% and 100%)
- Test concentrations: 0, solvent control, 0.5, 1.0, 2.0, 3.8, 7.6, 15.0 and 30.0 mg/l (chosen according to range finding tests)

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

13.1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% CL: 10.6 - 16.3 mg/l

Effect concentrations 2

Duration:

24 h

Dose descriptor:

NOEC

Effect conc.:

> 3.8 - < 7.6 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 3

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

8.25 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% CL: 6.53-10.5 mg/l

Effect concentrations 4

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

> 1 - < 2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Behavioural abnormalities: none
- Observations on body length and weight: none
- Other biological observations: none
- Mortality of control: no
- Other adverse effects control: none
- Abnormal responses: none
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: none
- Effect concentrations exceeding solubility of substance in test medium: Not applicable

Results with reference substance (positive control):

Not Applicable

Reported statistics and error estimates:

Probit method was used to establish the dose responses (immobilization in function of concentration) and the EC50 values

Any other information on results incl. tables

Table1 :Mobility inhibition*

Test substance concentration (mg/l)	Number of daphnia immobilized (% immobilized)
	24 hours	48 hours
0 Solvent control 0.50 1.0 2.0 3.8 7.6 15.0 30.0	0 (0) 0 (0) 0 (0) 0 (0) 0 (0) 0 (0) 4 (20) 11 (55) 19 (95)	1 (5) 0 (0) 0 (0) 0 (0) 1 (5) 3 (15) 7 (35) 16 (80) 20 (100)
* Inhibition correspond to “no swimming” during≥15 sec after shaking gently the daphniaglassbeaker

 

Table2: Water temperature, pH and Dissolved oxygen concentration

Test substance concentration (mg/l)	Temperature (°C)		pH		Dissolved oxygen (mg O2/l)
	0 hours	48 hours	0 hours	48 hours	0 hours	48 hours
0 Solvent control 0.50 1.0 2.0 3.8 7.6 15.0 30.0	20.6 20.6 20.7 20.7 20.7 20.7 20.7 20.7 20.8	20.5 20.5 20.5 20.5 20.5 20.4 20.5 20.5 20.4	7.9 7.9 7.9 7.9 7.9 7.9 8.0 8.0 8.0	7.9 7.7 7.7 7.7 7.7 7.7 7.7 7.7 7.6	8.0 8.3 8.2 8.3 8.2 8.1 8.2 8.1 8.2	8.5 8.2 8.1 8.1 8.2 8.2 8.1 8.0 7.9

 

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

1. No immobilization was observed in the control 2. Dissolved oxygen concentration greater or equal than 3mg/l in both control and test vessels

Executive summary:

Introduction. A study was performed to assess the acute toxicity of the test material to Daphnia Magna according to the OECD Guidelines for Testing of Chemicals N° 202 of April 1984.

Results & Discussions.Two preliminary range-finding studies performed within a concentration range of 1.00 to 100 mg/l indicated that immobilization started with a test concentration of 3.0 mg /l to be maximal with a test concentration of 50 mg/l.

In the final immobilization test, twenty daphnids (4 replicates of 5 animals) were exposed to aqueous solution containing 60 mg/l of the solvent HCO-40 and the following concentrations of the test material: 0, 0.50, 1.00, 2.00, 3.80, 7.60, 15.0 and 30.0 mg/l, for 48 hours at a temperature of 20 °C to 21°C under static test conditions. The number of immobilized Daphnia and any adverse reaction to exposure was recorded after 24 and 48 hours.

Analysis of the solution of the test material is not a requirement of the OECD TG 202 of April 1984 and was not performed in that study. Furthermore, the test material is expected to be stable in the test solution as shown in the study hydrolysis as a function of pH performed on the same test material (OECD TG 111, half life pH 7 > 1 year). The substance has been shown to be moderately soluble (>500 mg/l), and not volatile in the physico-chemical endpoints/studies. Therefore nominal concentrations were used to determine NOEC and EC50 values.

The 48-Hour EC50 for the test material to Daphnia magna was 8.25 mg/l with 95% confidence limits of 10.6 – 16.3 mg/l. The No Observed Effect Concentration (NOEC) was greater than 1.0 mg/l.