Reaction mass of potassium trifluoroacetate and potassium trifluoromethanesulphinate

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 2017-03-27 to 2018-12-28

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 207 (Earthworm, Acute Toxicity Tests)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: Ministry of environmental protection of the people's Republic of China, The Guidelines for the Testing of Chemicals - Effects on Biotic Systems, 2013, 207 Earthworm, Acute Toxicity Test

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Certificate from 25 September 2017

Analytical monitoring:

no

Vehicle:

yes

Remarks:

water

Details on preparation and application of test substrate:

Since the test substance was soluble in water, 5.0002 g of the test substance was dissolved in 500 mL water to prepare a 10 g/L stock solution, and then incorporated into formulated aritificial soil with deionised reverse osmosis water (see Table 1). The test solutions were mixed by a mixer to give the blank control and the test concentration of 1000 mg/kg with a nominal moisture content of 40-60% of the total water-holding capacity with the deionized water. The test matrix components were mixed evenly and distributed into 4 containers. Each container was loaded with approximately 750 g wet weight of the substrate.

Test organisms (species):

Eisenia fetida

Animal group:

annelids

Details on test organisms:

TEST ORGANISM
- Common name: Earthworm
- Source: Jiang Su province Jurong Stock Farm (ID: EF-MKT-170306).
- Age at test initiation (mean and range, SD): adult earthworms, no further information
- Weight at test initiation (mean and range, SD): 300 - 600 mg

ACCLIMATION
- Acclimation period: 14 days prior to use in the test
- Acclimation conditions (same as test or not): Earthworms were bred on a substrate consisting of 50% by volume peat and 50% by volume cow manure and kept under 20±2℃ for 7 days prior to testing. The test organisms were with clitellum and were transferred into artificial soil (without test substance) approximately 24 hours prior to the start of the test.

Study type:

laboratory study

Substrate type:

artificial soil

Limit test:

yes

Total exposure duration:

14 d

Test temperature:

20.0 - 20.2°C

pH:

Test initiation: 6.23 - 6.29
Test termination: 6.24 - 6.30

Moisture:

Test initiation: 25.24 - 25.55% (water/dry soil, w/w)
Test termination: 26.30 - 26.07% (water/dry soil, w/w)

Details on test conditions:

TEST SYSTEM
- Test container (material, size): 1L glass vessels with a plastic cover with small ventilation holes
- Amount of substrate: 750 g wet weight
- No. of replicates per treatment group: 4 (10 earthworms per replicate)
- No. of replicates per control: 4 (10 earthworms per replicate)
- No. of replicates per vehicle control: not applicable

OTHER TEST CONDITIONS
- Photoperiod: continuous illumination
- Light intensity: 641 - 678 lux

EFFECT PARAMETERS MEASURED
- Survival: for the controls and the test concentration, the number of dead earthworms was assessed on day 7 and 14 of exposure by emptying the soil medium onto a plate, sorting worms from the medium, testing their reaction to a mechanical stimulus at the front end, and recording the symptoms and deaths. Worms were considered as dead when they did not respond to a gentle mechanical stimulus to the front end. Due to rapid decomposition under test conditions, missing earthworms were also considered dead. At the completion of this assessment on day 7 of exposure, the soil medium and worms were replaced in the corresponding test container for the next 7 days of exposure.
- Weight: the total gross weights of the earthworms added to each vessel in the controls and the treatment groups were recorded on Day 0 before addition. The surviving earthworms in each vessel were weighed on Day 14.

OTHER PARAMETERS
At the beginning and the end of the test, soil moisture content and pH value of one test container were recorded in the blank control group and treatment group randomly. The temperature and light intensity in the climate chamber were recorded daily throughout the test.

VEHICLE CONTROL PERFORMED: no

RANGE FINDING TEST CONCENTRATIONS
- Range finding study: yes
- Test concentrations: 0 (blank control), 10, 100 and 1000 mg/kg dry soil weight (no replicates)
- Results used to determine the conditions for the definitive study: yes

Nominal and measured concentrations:

Nominal concentrations (definitive test): 0 (blank control) and 1000 mg/kg dry soil weight

Reference substance (positive control):

yes

Remarks:

chloroacetamide

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

Key result

Duration:

14 d

Dose descriptor:

LC50

Effect conc.:

> 1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

- Mortality at end of exposure period: No mortality occurred in the blank control group and in the 1000 mg/kg treatment group at the 7th day after application. The mortalities was 2.5% in the blank control group and 5% in the 1000mg/kg treatment group at the 14th day. The test fullfills the validity criterion since control mortality did not exceed 10%.
- Changes in body weight of live adults (% of initial weight) at end of exposure period: the weight reduction after 14 days in control and exposed groups was 18.3 and 14.7%, respectively.
- Morphological abnormalities: The results showed no abnormal morphology in the blank control group and treatment groups on Day 7 and 14.
- Behavioural abnormalities: The results showed no abnormal behavior in the blank control group and treatment groups on Day 7 and 14.
Results are provided in Table 2 and 3.

Results with reference substance (positive control):

The 14-days LC50 for chloroacetamide was 20.9 mg/kg dry soil weight. Tests from this reference substance conducted in the laboratory showed that the range of LC50 was between 4.57 to 31.6 mg/kg, so the 20.9 mg/kg is an acceptable value.

Reported statistics and error estimates:

Not applicable since the study was conducted as limit test.

Table 2. Mortality of Eisenia fetida exposed to the test substance and controls after 7 and 14 days of exposure

Parameter	Blank control		Treatment (1000mg/kg dry soil weight)
Duration (d)	7	14	7	14
Number of earthworm	40	40	40	40
Number of dead eartworms (A replicate)	0	1	0	1
Number of dead eartworms (B replicate)	0	0	0	0
Number of dead eartworms (C replicate)	0	0	0	1
Number of dead eartworms (D replicate)	0	0	0	0
Total	0	1	0	2
Mortality (%)	0	2.5	0	5

 

Table 3. Number and average body weight of the surviving earthworms at the beginning and the end of the test

Groups		No. of worms Day 0	Mean weight Day 0 (mg)	No. of worms Day 14	Mean weight Day 14 (mg)	Weight reduction 14 days±SD (%)
Blank control	A	10	512	9	424	18.27±4.76
	B	10	511	10	425
	C	10	554	10	415
	D	10	513	10	441
Treatment (1000 mg/kg dry soil weight)	A	10	580	9	502	14.69±4.71
	B	10	561	10	463
	C	10	557	9	509
	D	10	562	10	454

 

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of the test, the 7-day and 14-day LC50 were greater than 1000 mg/kg dry soil weight.

Executive summary:

The acute toxicity of the test item Reaction mass of potassium trifluoroacetate and potassium trifluoromethanesulphinate to Eisenia fetida was investigated in a GLP-compliant study performed in a 14 day artificial soil test according to OECD Guideline No. 207. Based on the results of range-finding test,one treatment group and one blank control group which had four replicates of 10 worms perreplicatewere included inthe limittest. The nominal concentration of the treatment group was1000 mg/kg dry artificial soil weight. The number of mortalities were determined after 7 and 14 days exposure.

The mortality of the earthworm in the blank control group was 2.5%,which was not more than 10 per cent, so the test was valid. Under the tested conditions, the 7-Day LC50 and the 14-Day LC50 for the test substance to earthworms (Eisenia fetida) based on the nominal test concentrations were both higher than 1000mg/kg dry soil weight.

Description of key information

The acute toxicity of the test item to Eisenia fetida was investigated in a GLP-compliant study performed in accordance with OECD Guideline No. 207. Under the conditions of the test, the 7-Day LC50 and the 14 -Day LC50 were greater than 1000 mg/kg dry soil weight.

Additional information

The acute toxicity of the test item to Eisenia fetida was investigated in a GLP-compliant study performed in accordance with standard methods, without deviations. The study is considered as reliable (Klimisch 1) and is selected as a key study for the endpoint.