Dipraseodymium trioxide

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

6 November 2000 to 10 November 2000

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Justification for type of information:

Read-across performed with structurally similar substance.

Reason / purpose for cross-reference:

other: read-across target

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: The test material, practically insoluble in water, was introduced in the test medium by weighed adequate quantity and was dispersed by stirring. The dissolution was continued during a period of 168 hours to be sure that the equilibrium was reached and "soluble fraction" stable during the test. After correction of evaporation by addition of deionised water, stirring was stopped and the different suspensions were decanted for a resting period of 4 hours.
- Controls: yes, test water without test material
- Evidence of undissolved material (e.g. precipitate, surface film, etc): no

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: Zebrafish
- size/weight: 30.4 mm (mean); 0.3 g (mean)
- Food: no feeding during the test
- Source: Pisciculture Exotique, Dourdan (91), France
- Food: TetraMin Tetra

ACCLIMATION
- Acclimation period: 2 weeks
- Acclimation conditions: same as test; reconstituted water (ISO 7346) with continual aeration and filtering device
- Health during acclimatation: mortality less than 1 % within the adaptation period.

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Post exposure observation period:

none

Hardness:

250 ± 25 mg/L as CaCO3

Test temperature:

24 ± 1 °C

pH:

7.17 - 7.91

Dissolved oxygen:

4.5 - 8.2 mg O2/L

Salinity:

not applicable

Nominal and measured concentrations:

100 mg/L (nominal)

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type : 5 litre glass beakers
- Fill volume: 4 L of reconstituted water
- Aeration: none during the test, but dilution water was previously saturated with oxygen before the start of the test
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: 0.76 g/L

WATER PARAMETERS
- Source: reconstituted water-ISO 7346
- Conductivity: < 5 µs/cm
- Intervals of water quality measurement : pH and dissolved oxygen were measured after 0, 24, 48, 72 and 96 h of exposure

OTHER TEST CONDITIONS
- Photoperiod: about 12 h light daily
- Light intensity: natural diffused lighting

EFFECT PARAMETERS MEASURED : Immobility and absence of respiration motion observed after 3, 24, 48, 72 and 96 h of exposure

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Key result

Duration:

96 h

Dose descriptor:

LL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

NOELR

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

No mortality was observed during the test, either in control or test groups.
No abnormal response of the fish was observed during the test period.

Results with reference substance (positive control):

- Results with reference substance valid? yes
- Mortality: no data
- 24h LC50: 226 mg/L (K2Cr2O7). This calculated value was between the interval (200 - 400 mg/L) formerly defined by the method, and was used to validate the selected fish batch.

Validity criteria fulfilled:

yes

Conclusions:

Using a limit test with a saturated solution at 100 mg/L, the test material had no acute toxic effect on the fish Danio rerio.

Executive summary:

The 96 h acute toxicity of the test material to Danio rerio was studied under static conditions, according to the standardised guideline OECD 203.

Fish were exposed to the test material in a saturated solution at a nominal loading rate of 100 mg /L. No mortality was observed during the test, neither in the control nor in the group exposed to the test material.

Under the conditions of this study the 96 hour LL50 and NOELR were thus >100 mg/L and ≥100 mg/L, respectively.

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study conducted on read-across material

Justification for type of information:

Read-across performed with structurally similar substance.

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

96 h

Dose descriptor:

LL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

NOELR

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Description of key information

Read-across performed with structurally similar substance.

Under the conditions of the study, the 96 hour LL50 and NOELR were >100 mg/L and ≥100 mg/L, respectively.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

100 mg/L

Additional information

Read-across performed with structurally similar substance.

The 96 h acute toxicity of the test material to Danio rerio was studied under static conditions, according to the standardised guideline OECD 203. The study was awarded a reliability score of 2 in accordance with the criteria set forth by Klimisch et al. (1997).

Fish were exposed to the test material in a saturated solution at a nominal loading rate of 100 mg /L. No mortality was observed during the test, neither in the control nor in the group exposed to the test material.

Under the conditions of the study the 96 hour LL50 and NOELR were thus >100 mg/L and ≥100 mg/L, respectively.