cis-2-(2,4-dichlorophenyl)-2-(1H-imidazol-1-ylmethyl)-1,3-dioxolane-4-ylmethyl methanesulphonate monohydrochloride

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2015-09-21 to 2015-10-21

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: I14KB4717
- Expiration date of the lot/batch: 206-11-25 (retest date)
- Purity test date: 2014-12-13 (certificate of analysis release date)

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: At room temperature
- Stability under test conditions: no data

Analytical monitoring:

yes

Details on sampling:

- Sampling method: samples for possible analysis were taken from all test concentrations and the control at t=0 and t=48h. 2.0 mL of volume was taken from the approximate centre of the test vessels. At the end of the exposure period, the replicates were pooled at each concentration before sampling
- Sample storage conditions before analysis: the samples were stored in a freezer. Additionally, reserve samples of 2.0 mL were taken for possible analysis

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method:
Combined limit/range-finding test:
Based on the data provided by the Sponsor, the solubility of the test substance in water was 39.3 g/L. Therefore, the preparation of test solutions started with a loading rate of 100 mg/L (duplicate samples)applying a short period of magnetic stirring (47-51 minutes at room temperature) where after the solutions were hazy and contained flocks. This was unexpected as in a solubility test performed for the biodegradation study the test item dissolved completely at 10 g/L. Therefore, these solutions were discarded. In order to check whether there was an issue with the solubility of the test item or whether precipitation of the salts from the medium would be causing the haziness and the formation of flocks, a new solution was prepared in Milli-RO water (100 mg/L). After a 3-minute period of magnetic stirring the solution was clear and colourless confirming sufficient solubility of the test item in water.
Subsequently salts were added to reach the concentrations described in paragraph 6.3 of the report (adjusted ISO medium). As the solution remained clear and colourless it was used as the highest concentration.
The lower test concentrations were prepared by subsequent dilutions of the highest concentration in test medium. The final test solutions were all clear and colourless at the start of the test.

Final test:
Based on the observations made in the combined limit/range-finding test and in agreement with the sponsor, the solutions for the final test were prepared differently. A Saturated Solution (SS) was prepared at a loading rate of 100 mg/L applying a one-hour period of magnetic stirring. The obtained mixture was allowed to settle for 26 minutes (at room temperature). Successively, it was filtered through a preconditioned membrane filter (RC55, Whatman) and used as the highest test concentration. The lower test concentrations were prepared by subsequent dilutions of the highest concentration

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water-flea
- Source: in-house laboratory culture with a known history
- Age at study initiation (mean and range, SD): < 24 h (from parental daphnids of more than 2 weeks old, maximum age 4 weeks)
- Method of breeding: 250 newborn daphnids (i.e. less than 3 days old) are placed into 5 liters of medium in an all-glass culture vessel. Medium is M7. After 7 days of cultivation half of the medium is renewed twice a week.
- Feeding during cultivation: fresh water algae, daily
- Feeding during test: no
ACCLIMATION
- Acclimation period: not relevant

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

180 mg/L as CaCO3

Test temperature:

19-20°C

pH:

At t= 0h: 7.6 - 8.1
At t= 48h: 7.8 - 8.1

Dissolved oxygen:

At t= 0h: 8.4 - 9.3
At t= 48h: 9.2 - 9.4

Salinity:

not relevant

Nominal and measured concentrations:

Range-finder:
Nominal concentrations (mg/L) at t=0h: 10, 100
Nominal concentrations (mg/L) at t=48h: 1, 100
Measured concentrations (mg/L) at t=0h: 10,6, 99,7
Measured concentrations (mg/L) at t=48h: 1.06, 69.3

Final test
Nominal concentrations (mg/L): 0, 2.2, 4.6, 10, 22, 46 and 100% of a SS prepared at 100 mg/L
Measured concentrations (mg/L) at t=0h: 0.0040, 1.25, 2.53, 5.55, 12.3, 25.3, 47.8
Measured concentrations (mg/L) at t=48h: 0.0036, 1.27, 2.57, 5.60, 5,71, 10.3, 23.8, 55.5

Details on test conditions:

TEST SYSTEM
- Test vessel: beaker
- Material, size, headspace, fill volume: 100 mL, glass beaker filled with 80mL
- Aeration: not during the test
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- Test medium: adjusted ISO medium

OTHER TEST CONDITIONS
- Photoperiod: 16h light daily

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Immobility was defined as those organisms which are not able to swim within 15 seconds after gentle agitation of the test container and was monitored after 24 and 48 hours of continuous treatment with the test substance.

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2.1
- Range finding study
- Test concentrations: 0,10, 1.0, 10 and 100% mg/L
- Results used to determine the conditions for the definitive study: yes

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

14 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% C.L.: 10-18 mg/L

Details on results:

- Mortality of control: none
- Other adverse effects control: no
- Abnormal responses: none

Results with reference substance (positive control):

- Results with reference substance valid?
- Mortality: no
- EC50/LC50: 48h-EC50 = 0.39 mg/L. the sensitivity of the daphnia was within the range determined with the historical data collected at WIL Research Europe.

Reported statistics and error estimates:

The EC50 values were calculated from the Weibull analysis of the percentage of affected daphnids and the logarithms of the corresponding test item concentrations using the maximum likelihood estimation method.

Validity criteria fulfilled:

yes

Conclusions:

The acute toxicity of T001202 to Daphnia magna was determined in a 48-hour static test according to the OECD guideline 202.
Based on measured test concentrations, the 48-h EC50 was determined to be 14 mg T001202/L (95% C.L. 10-18 mg/L). The results of the test can be considered reliable without restriction.

Description of key information

The study of Tobor-Kaplon (2016), investigating the acute toxicity of T001202 in Daphnia magna according to OECD guideline 202, was considered as the key study for endpoint coverage. An EC50 of 14 mg/L (based on measured test concentrations) was found after an exposure of 48 hours in a static test in freshwater. Based on the results it can be concluded that T001202 is harmful to aquatic invertebrates.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

14 mg/L