Praseodymium(III,IV) oxide

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

6 November 2000 - 10 November 2000

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Non GLP compliant study conducted in accordance with generally accepted scientific principles, possibly with incomplete reporting or methodological deficiencies, which do not affect the quality of the relevant results.

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 mgO2/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
- No further data

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

Duration:

96 h

Dose descriptor:

LL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

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. The 96 hour LL50 and NOELR were thus >100 mg/L and≥100 mg/L, respectively.

Description of key information

The 96 hour LL50 and NOELR were >100 mg/L and ≥100 mg/L, respectively.

Additional information

The key study was conducted in accordance with the standardised guideline OECD 203. It was assigned a reliability score of 2 in accordance with the criteria detailed by Klimisch (1997).

The 96 h acute toxicity of the test material to Danio rerio was studied under static conditions. Fish were exposed to the test material 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. The 96 hour LL50 and NOELR were thus >100 mg/L and ≥100 mg/L, respectively.