3,20-bis(ethylenedioxy)pregna-5,7-diene

Toxicity to soil macroorganisms except arthropods

Administrative data

Endpoint:

toxicity to soil macroorganisms except arthropods: short-term

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2013-09-23 to 2014-03-26

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Performed in accordance with OECD method and GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2014

Report date:

2014

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 207 (Earthworm, Acute Toxicity Tests)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

3,20-bis(ethylenedioxy)pregna-5,7-diene

EC Number:

243-175-0

EC Name:

3,20-bis(ethylenedioxy)pregna-5,7-diene

Cas Number:

19592-55-3

Molecular formula:

C25H36O4

IUPAC Name:

(1S,3aR,9aR,9bS,11aS)-9a,11a-dimethyl-1-(2-methyl-1,3-dioxolan-2-yl)-1,2,3,3a,6,8,9,9a,9b,10,11,11a-dodecahydrospiro[cyclopenta[a]phenanthrene-7,2'-[1,3]dioxolane]

Test material form:

solid: crystalline

Sampling and analysis

Analytical monitoring:

no

Test substrate

Vehicle:

no

Test organisms

Test organisms (species):

Eisenia fetida

Animal group:

annelids

Details on test organisms:

The earthworms were purchased from Shanghai Yinquan Agriculture Development
Co., Ltd. (ID: EF-MKT-130603). All newly acquired earthworms were quarantined and observed for 14 days prior to use in the test. Earthworms are bred on a substrate consisting of 50% by volume peat and 50% by volume cow manure and kept under ,
20 ± 2·c for 7 days prior to testing. The test organisms were with clitellum and were
transferred into artificial soil (without test substance) approximately 24hours prior to
the start of the test. At the start of the test, the adult earthworms used originated from ..
the same population, were with clitellum and wet weight of 300 to 600 mg.

Study design

Study type:

laboratory study

Substrate type:

artificial soil

Limit test:

yes

Total exposure duration:

14 d

Remarks:

The nominal concentration is 1000 mg/kg.

Post exposure observation period:

none

Test conditions

Test temperature:

Temperature of climate chamber is measured daily.The measured temperature of climate chamber remained at 19.4 to 20.1 ·c throughout the study, which should be in the range of 18-22 °C.

pH:

The pH of the artificial soil was adjusted to 6.0 +0.5 by the addition of calcium carbonate. The measured pH values and soil moisture content in the control and test cultures were 5.79 - 5.85 at initiation and 6.13 to 6.24 at termination

Moisture:

Moisture content of the test substrate was adjusted to 40-60 % by mass of the total water-holding capacity with the deionized water. The measured value was 54% before the test initiation. In the limit / definitive test, the moisture content of the artificial soil was in the range of 22%- 32%. Soil moisture content in the control and test groups were 28.81 to 29.80 at initiation and 27.93 to 29.47 at termination.

Details on test conditions:

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

no replicates in range finding test.

4 replicates in limit test.

SOURCE AND PROPERTIES OF SUBSTRATE (if soil)

A defined artificial soil was used as a basic test substrate with the following composition ,

sphagnum peat 10% w/w;
kaolinite clay; 20% w/w and
silica sand (screened with 0.2 mm sieve); 70% w/w.

OTHER TEST CONDITIONS
- Photoperiod:The vessels were covered and maintained under continuous illumination (400-498 lux)
- Light intensity:bThe light intensity was 473-510 lux which should be in the range of 400-8001ux.

The total gross weights of the worm added to each beaker of the controls and test groups were recorded on Day O before addition to the test or control vessels. The surviving earthworms of each beaker were weighed on Day 14.

Any mortalities were recorded at 7 and 14 days after the start of treatment.

Nominal and measured concentrations:

range finding 10, 100 and 1000 mg/kg
limit test 1000 mg/kg - 4 replicates with a blank control

Reference substance (positive control):

yes

Remarks:

chloroacetamide

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

7 d

Dose descriptor:

LC50

Effect conc.:

> 1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Effect concentrations 2

Duration:

14 d

Dose descriptor:

LC50

Effect conc.:

> 1 000 mg/kg soil dw

Nominal / measured:

not specified

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

In range-finding test, cumulative mortality data from the exposure of Eisenia fetida to the test substance showed no mortalities at 1000 mg/kg on the 7th day and 14th day.

The mortality rate of the control group were 0% at 7th day and 2.5% at 14th day, the mortality rate of the 1000 mg/kg dry weight soil treatment group were both 2.5% at 7th and 14th day. Compared with 1000 mg/kg treatment group, there was no significant differences)
(According to the result of F-Test, p=0.46, p>0.05) of the variance t test at the end of the test

Results with reference substance (positive control):

The most recent test with chloroacetamide was performed from 16 Oct. 2013 to 30 Oct. 2013 (14 days test). In this study, the reference substance was tested at 5 concentrations of 3.75, 7.50, 15, 30 and 60 mg/kg dry artificial soil weight. The Mortality of chloroacetamide treatment group
were shown to be between 2.5% to 100%. The 14-days LC50 for chloroacetamide was 15.33 mg/kg dry soilweight.
Test from this reference substance conducted over 5 years in the laboratory and show that the range of LC50 is between 10 to 31 mg/kg, so the 15.33 mg/kg was an acceptable value.

Reported statistics and error estimates:

2.5% of the earthworms died in the control group. Thus, the test fullfills the validity criterion that control mortality should not exceed 10%.
The differences of the average body weight of the surviving earthworms between the control group and the treatment groups were determined by using the F-Test at the end of the study. The data analyses were carried out with Toxcalc software v5 .0.26.

Any other information on results incl. tables

Number and average body weight of the surviving earthworms atthe beginning and the end of the definitivetest

 

 

Concentration Nr of worms day 0 Mean weight day 0(mg) Nr of worms day14 Mean weight day14(mg) Weight reduction14days(%)± standard deviation.   Significance     Control A 10 332 10 298     -2.98±10.9%     - B 10 365 9 374 c 10 324 10 334 D 10 322 10 375     Treatments 1000mg/kg A 10 346 9 300     15.11±2.42%     n.s B 10 369 10 320 c 10 336 10 284 D 10 326 10 266

-:nocalculation;

n.s.not significantly different compared to the control, F-test, p>0.05;

s.significantly different compared to the control, F-test,p<0.05

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Expressed as nominal test substance concentration, the median lethal concentrations of Proketal on Eisenia fetida (earthworms) are as follows :
The 7-day LC50 value > 1000 mg/kg dry soil weight.
The 14-day LC50 value > 1000 mg/kg dry soil weight.