Ruthenium, dichloro[1,3-dihydro-4,5-dimethyl-1,3-bis(2,4,6-trimethylphenyl)-2H-imidazol-2-ylidene](2-thienylmethylene)(tricyclohexylphosphine)-, (SP-5-41)-

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:

2016-06-14 to 2016-10-20

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

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

slowly decomposition in water

Analytical monitoring:

yes

Details on sampling:

At the start of the test (0h), the control, and following test solutions: 6.25; 25, and 100 mg/l were analyzed before division to the test vessels, each group: 4 samples of 10 ml
After 24 h exposure, all replicates of control and of all five test concentrations were analyzed, each group: 4 samples of 10 ml
At the end of the test (48h), all replicates of of the control, and following test solutions 6.25; 25, and 100 mg/l were analyzed before division to the test vessels, each group: 4 samples of 10 ml
The samples were filtered (0.45µm syring filter), filled in plastic centrifuge tubes and stored (<8weeks) in the fridge (5°C +-3°C). Of each treatement, one of the samples from 0h; 24 h; and 48 h was sent to the analytical laboratory and analyzed. The remaining samples were stored as retain samples in the fridge until finalization of the study

Vehicle:

no

Details on test solutions:

The stock solution was prepared by adding 99.9 mg test item to 1000 ml ISO medium and shaking for 24 h using overhead shaker at 24.2-25.1 °C in the dark. As the test substance is a very poorly soluble solid, the stock solution was filtered through a fibre glass filter with retaining range till 0.6 µm. The filter was prepared by rinsing with purified water and preconditioning with ca 250 ml stock solution (which was discarded), to reduce adsorption of the test item. The negative control (ISO-medium) was treated in the same way as the test substance solution. Into each test vessel, 40ml test substance solution and ISO medium was transferred,

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Strain/clone: Daphnia magna Straus
- Source: Federal Environment Agency Berlin
- Feeding during test: no
- Food type: Desmodesmus subspicatus
- Amount: 0.1 mg C/daphnid/day

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

ISO 6341 medium were used

Test temperature:

19.8-21.4 °C

pH:

control: 7.0-7.8
test solution: 7.5-7.9

Dissolved oxygen:

control: 7.3-7.9 mg/l
test solution: 7.3-7.7 mg/l

Salinity:

not applicable

Nominal and measured concentrations:

nomial loading rates: o; 6.25; 12.5; 25; 50, and 100 mg/l

Details on test conditions:

TEST SYSTEM
- Test vessel: glass beakers 50 ml
- Type (delete if not applicable): open
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: ISO 6341 medium without EDTA
OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16h light; 8 h dark
EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : swimming capability was determined after 24 h and 48 h exposure, The pH as well as O2 concentrations were measured at the start (ßh) and at the end of the test (48h), temperature was measuered continuously
RANGE-FINDING STUDY
- Test concentrations: preliminary test without GLP, nominal loading rates of 10, 40, 160 mg/l of not filtered test material
- 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:

EL50

Effect conc.:

19.2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

LOELR

Effect conc.:

12.5 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

NOELR

Effect conc.:

6.25 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Other biological observations: no
- Mortality of control: no
- Other adverse effects control: no
- The measured Ru-concentrations in the test substance treatments were below the limit of quantification (< 1µg/l) up to 1.6 µg/l. The Ru-concentrations in the control were below the limit of quantification

Results with reference substance (positive control):

- Results with reference substance valid? yes
- Relevant effect levels: EC50(24h) = 1.30 mg/l ; EC50(48h) = 0.82 mg/l

Reported statistics and error estimates:

statistical evaluation with ToxRat Professional 3.2.1

Table 1: Immobility after 24 h and 48 h exposure

Nominal test item Loading rate [mg/l]	Mobile Daphnia (replicates 1-4)												Immobility [%]
	0 h				24 h				48 h				24 h	48 h
	1	2	3	4	1	2	3	4	1	2	3	4
Control	5	5	5	5	5	5	5	5	5	5	5	5	0	0
6.25	5	5	5	5	5	5	5	5	5	5	4	5	0	5
12.5	5	5	5	5	5	4	5	4	3	5	4	3	10	25
25	5	5	5	5	2	3	4	1	2	3	3	1	50	55
50	5	5	5	5	0	1	0	1	0	0	0	0	90	100
100	5	5	5	5		0	0	0	0	0	0	0	100	100

Validity criteria fulfilled:

yes

Conclusions:

The test substance is classified as harmful to aquatic life with long lasting effects.

Executive summary:

A valid static Daphnia magna acute immobilisation test with the test substance according to OECD Guideline under GLP was performed. The EL50 loading rate of 19.2 mg/l after 48 hours was determined

Description of key information

The test substance is classified as harmful to aquatic life with long lasting effects.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

19.2 mg/L