Cyclopentane, methoxy-

Toxicity to soil macroorganisms except arthropods

Link to relevant study record(s)

Reference

Endpoint:

toxicity to soil macroorganisms except arthropods: short-term

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 2013-03-12 to 2013-05-17

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 207 (Earthworm, Acute Toxicity Tests)

Version / remarks:

1984

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

Batch No.: 2820246
Purity: ≥99.9%

Analytical monitoring:

no

Vehicle:

yes

Remarks:

water

Details on preparation and application of test substrate:

Since the test substance was soluble in water. An amount of test substance was dissolved in water to prepare 1000 mg/L stock solution, then incorporated into formulated artificial soil with deionised reverse osmosis water. The treatment groups were prepared by test matrix component of test substance stock solution, Silica sand, Deionized water and Basic test substrate. These were mixed by hand to give control, 29, 53, 95, 171, 309, 556 and 1000 mg/kg respectively with a nominal moisture content of approximately 35% of dry weight.

Test organisms (species):

Eisenia fetida

Animal group:

annelids

Details on test organisms:

TEST ORGANISM
- Common name: Eisenia fetida
- Source: Shanghai Yinquan Agriculture Development Co., Ltd.
- Weight at test initiation (mean and range, SD): wet weight: 300 to 600 mg

ACCLIMATION
- Acclimation period: 24 hours
- Acclimation conditions: same as test

Study type:

laboratory study

Substrate type:

artificial soil

Limit test:

no

Total exposure duration:

14 d

Test temperature:

20.0-21.0 °C

pH:

ranged from 6.05 at initiation and 6.11 at termination

Moisture:

37.51% at initiation and 29.66% at termination.

Details on test conditions:

TEST SYSTEM
- Test container (material, size):1 litre closed glass vessel
- Amount of soil or substrate: 750 wet weight of substrate
- No. of organisms per container (treatment): 10
- No. of replicates per treatment group: 4
- No. of replicates per control: 4

SOURCE AND PROPERTIES OF SUBSTRATE (if soil)
- Composition (if artificial substrate): Sphagnum peat: 10% w/w; Kaolinite clay: 20% w/w; Silica sand (screened with 0.2 mm sieve): 70% w/w
- Pretreatment of soil: The pH of the artificial soil was adjusted to 6.0±0.5 by the addition of calcium carbonate.

OTHER TEST CONDITIONS
- Photoperiod: continous
- Light intensity: 620 lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
The gross weight of each beaker of the controls and 1000 mg/kg was recorded on Day 0 before addition to the test or control vessels. The surviving earthworms of each beaker were weighed on Day 14.
Any mortalities were recorded 7 and 14 days after the start of treatment.
The temperature of climate chamber and light intensity were recorded daily hroughout the test.
Soil moisture content and pH were recorded at the start and termination of the test.

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 1.8
- Range finding study
- Test concentrations: 10, 100, 1000 mg/kg
- Results used to determine the conditions for the definitive study: The results showed no mortalities at 10mg/kg and 100mg/kg on the 7th and 14th day and all died at 1000 mg/kg on the 7th day.

Nominal and measured concentrations:

Nominal: 29, 53, 95, 171, 309, 556 and 1000 mg/kg

Reference substance (positive control):

yes

Key result

Duration:

14 d

Dose descriptor:

LC50

Effect conc.:

> 676 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

7 d

Dose descriptor:

LC50

Effect conc.:

> 756 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

Mortalities in control group on 7th and 14th day both were 0%. Mortalities in the treatment groups which were 29 mg/kg and 95 mg/kg of on the 7th and 14th day were 0%; 53 mg/kg group was 2.5% on the 7th day and 12.5% on the 14th day; 171 mg/kg group were 2.5% on the 7th day and 5% on the 14th day; 309 mg/kg group was 0% on the 7th day and 2.5% on the 14th day; 556 mg/kg group was 5% on the 7th day and 17.5% on the 14th day; 1000 mg/kg group was 92.5% on the 7th day and 100% on the 14th day.
There was no statistically significant change in the average body weight of the surviving earthworms in the control group at the beginning and at the end (According to the result of t test, p=0.6333, p>0.05).

Results with reference substance (positive control):

- Results with reference substance valid? yes
- Relevant effect levels: 14d-LC50: 11 mg/kg dry soil weight (95% confidence limits: 10 -12 mg/kg dry soil weight)

Reported statistics and error estimates:

Data were analyzed by appropriate statistical methods to calculate the LC50with 95% confidence limits using software Toxcalc v5.0.26.
The differences of the average body weight of the surviving earthworms between the control group and the treatment groups were determined oy using the t-Test at the end of the study. The data treatment were carried out with software Toxcalc v5.0.26.

Validity criteria fulfilled:

yes

Conclusions:

Expressed as nominal test substance concentration, the median lethal concentrations of test item on Eisenia fetida are as following:
The 7 days LC50 value was higher than 756 mg/kg dry soil weight.
The 14 days LC50 value was higher than 676 mg/kg dry soil weight.

Executive summary:

The acute toxicity of the test substance to Eisenia fetida was determined in a 14 days artificial soil test according to OECD 207.

Based on the results of range-finding test, 7 treatment groups and one control group which had four replicates of 10 worms per concentration were included in definitive test. The nominal concentrations of the treatment groups were 29, 53, 95, 171, 309, 556 and 1000 mg/kg dry artificial soil weight. The number of mortalities were determined after 7 and 14 days exposure.

Mortality of the earthworms in control group was 0, which was not more than 10 percent. So the test was valid.

Under present condition, the 7-Day LC50 for the test substance to earthworms (Eisenia fetida) based on nominal test concentrations was higher than 756 mg/kg; the 14-Day LC50 was higher than 676 mg/kg.

Description of key information

Acute study:

The 7-Day LC50 for the test substance to earthworms (Eisenia fetida) based on nominal test concentrations was higher than 756 mg/kg; the 14-Day LC50 was higher than 676 mg/kg.

Key value for chemical safety assessment

Short-term EC50 or LC50 for soil macroorganisms:

676 mg/kg soil dw

Additional information

The acute toxicity of the test substance to Eisenia fetida was determined in a 14 days artificial soil test according to OECD 207.

Based on the results of range-finding test, 7 treatment groups and one control group which had four replicates of 10 worms per concentration were included in definitive test. The nominal concentrations of the treatment groups were 29, 53, 95, 171, 309, 556 and 1000 mg/kg dry artificial soil weight. The number of mortalities were determined after 7 and 14 days exposure.

Mortality of the earthworms in control group was 0, which was not more than 10 percent. So the test was valid.

Under present condition, the 7-Day LC50 for the test substance to earthworms (Eisenia fetida) based on nominal test concentrations was higher than 756 mg/kg; the 14-Day LC50 was higher than 676 mg/kg.