Lithium amide

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:

2017-01-17 to 2017-01-19

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)

Version / remarks:

adopted 13th April 2004

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

adopted 30th May 2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Expiration date of the batch: 2017-03-11

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Room Temperature (20 ± 5 °C); Keep under inert gas

OTHER SPECIFICS: fine powder, white to grey

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 4.6, 10, 22, 46, 100 mg/L

Vehicle:

no

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Strain/clone: Berlin
- Source: Umweltbundesamt Berlin
- Age of parental stock: between 0 and 24 hours
- Feeding during test: No

ACCLIMATION
- Acclimation conditions (same as test or not): same as test conditions
- Type of food: unicellular green algae (Desmodesmus subspicatus)
- Health during acclimation (any mortality observed): No.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

250 mg CaCO3/L

Test temperature:

19.2 - 20.9 °C

pH:

7.6 - 7.8

Dissolved oxygen:

8.5 - 9.5

Salinity:

Not applicable

Nominal and measured concentrations:

nominal concentration:
4.6, 10, 22, 46, 100 mg/L
calculated concentration (based on measured nitrogen and ammonia concentration):
4.5, 9.7, 21.7, 46, 98.2 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: flasks
- Type: closed
- Material, fill volume: glass, 65 mL
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- No. of vessels per vehicle control (replicates): 4


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: dilution water as demanded in the guidelines
- Culture medium different from test medium: no

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16/8 hours, using neon tubes

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): Immobilisation every 24 hours

VEHICLE CONTROL PERFORMED: yes

Reference substance (positive control):

yes

Remarks:

Potassium dichromate K2Cr2O7 (CAS No. 7778-50-9)

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

22 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

10 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

25 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

22 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Mortality of control: No
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: No

Results with reference substance (positive control):

- Results with reference substance valid? Yes. The 24h-EC50 value was determined as 1.8 mg/L, lying within the range of 0.6 - 2.1 mg/L which is mentioned in the OECD guideline.

Reported statistics and error estimates:

The estimation of the biological results was accomplished using the software ToxRat® Professional, version 3.2.1.

The three highest concentrations showed toxicity between 55 and 100% immobilisation. None of the animals were immobilised in the blank control.

Nominal Concentration in mg/L	Immobility 24 hours					Immobility 48 hours
	absolute				in %	absolute				in %
Blank control	0	0	0	0	0	0	0	0	0	0
4.6	0	0	0	0	0	0	0	0	0	0
10	0	0	0	0	0	0	0	0	0	0
22	0	1	2	1	20	3	3	3	2	55
46	5	5	5	5	100	5	5	5	5	100
100	5	5	5	5	100	5	5	5	5	100

Validity criteria fulfilled:

yes

Conclusions:

In a 48 h immobilisation study with Daphnia magna, an EC50 of 22 mg/L and a NOEC value of 10 mg/L was determined.

Executive summary:

Short term toxicity of the test substance was determined according to OECD guideline 202. One valid experiment was performed. The study was performed using 5 concentrations ranging from 4.6 to 100 mg/L. For each test concentration, 20 daphnia were exposed (4 replicates á 5 animals) to the test item for 48 hours in a static test system. After 24 and 48 hours, the immobilised Daphnia were counted.

The three highest concentrations showed toxicity between 55 and 100 % immobilisation. None of the animals were immobilised in the blank control.

Potassium dichromate K2Cr2O7 (CAS No. 7778-50-9) was used as positive control in a current reference study to assure that the test conditions are reliable. At the start and at the end of the test, the content of the test item in the test solutions was determined by NH4+-determination using a photometric method. The measured concentrations laid between 97 % and 100 % of the nominal concentrations at the beginning of the test and between 96 % and 100 % of the nominal concentrations at the end of the test. Therefore, the determination of the results was based on the nominal concentrations.

The following results were determined for the test item lithium amide (species: Daphnia magna).

48h-NOEC = 10 mg/L

48h-LOEC = 22 mg/L

48h-EC50 = 22 mg/L

Description of key information

In a 48 h immobilisation study with Daphnia magna, an EC50 of 22 mg/L and a NOEC value of 10 mg/L was determined.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

22 mg/L

Additional information

Short term toxicity of the test substance was determined according to OECD guideline 202. One valid experiment was performed. The study was performed using 5 concentrations ranging from 4.6 to 100 mg/L. For each test concentration, 20 daphnia were exposed (4 replicates á 5 animals) to the test item for 48 hours in a static test system. After 24 and 48 hours, the immobilised Daphnia were counted.

The three highest concentrations showed toxicity between 55 and 100 % immobilisation. None of the animals were immobilised in the blank control.

Potassium dichromate K2Cr2O7 (CAS No. 7778-50-9) was used as positive control in a current reference study to assure that the test conditions are reliable. At the start and at the end of the test, the content of the test item in the test solutions was determined by NH4+-determination using a photometric method. The measured concentrations laid between 97 % and 100 % of the nominal concentrations at the beginning of the test and between 96 % and 100 % of the nominal concentrations at the end of the test. Therefore, the determination of the results was based on the nominal concentrations.

The following results were determined for the test item lithium amide (species: Daphnia magna).

48h-NOEC = 10 mg/L

48h-LOEC = 22 mg/L

48h-EC50 = 22 mg/L