Lanthanum trihydroxide

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:

from 30 oct 2000 to 29 nov 2000

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods with acceptable restrictions

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 substance 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 item
- 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
- Source: Pisciculture Exotique - Dourdan, 91, France
- size/weight: 30.4 mm, 0.3 g;
- Method of breeding: The fish were bred in reconstituted water (ISO 7346) with continual aeration and filtering device
- Food: TetraMin Tetra during breeding (no feeding during the test);

ACCLIMATION
- Acclimation period: 2 weeks
- Acclimation conditions: same as test
- 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

Hardness:

250 mg/L ± 25 mg/L as CaCO3.

Test temperature:

24°C ± 1°C

pH:

7.17-7.84

Dissolved oxygen:

4.5-8.3 mg/L

Salinity:

not applicable

Nominal and measured concentrations:

100 mg/l

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type : 5 litres 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

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

NOELR

Effect conc.:

>= 100 mg/L

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) formely defined by the method, and was used to validate the selected fish batch.

Validity criteria fulfilled:

yes

Conclusions:

Using a limit test at 100 mg/L, lanthanum oxide had no acute toxic effect on the fish Danio rerio.

Executive summary:

The 96hr-acute toxicity of lanthanum oxide to Brachydanio rerio was studied under static conditions according to OECD Guideline 203. Brachydanio rerio were exposed to control and test chemical at nominal concentration of 100 mg /L. Mortality/immobilization were observed daily. No mortality was observed during the test, neither in the control nor in the group exposed to the test item. The 96 hour LL50 and NOELR were thus > 100 mg/L.

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 to structurally similar substance, lanthanum oxide, is justified on the basis that ecotoxicological effects will be driven by the metal cation species (La3+) which is analogous to the registered substance and the read-across substance.

Reason / purpose for cross-reference:

read-across source

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)

Description of key information

96 h LL50 > 100 mg/L, 96 h NOELR >=100 mg/L, Brachydanio rerio, OECD 203, EU Method C.1, INERIS 2000 (read across from lanthanum oxide).

Additional information

The 96hr-acute toxicity of lanthanum oxide to Brachydanio rerio was studied under static conditions according to OECD Guideline 203. Brachydanio rerio were exposed to control and test chemical at nominal concentrations of 100 mg /L. Mortality/immobilization were observed daily. No mortality was observed during the test, neither in the control nor in the group exposed to the test item. The 96 hour LL50 and NOELR were thus > 100 mg/L.

This is the only reliable short-term toxicity study on fish that is available for the substance. It has been performed on a structural analogue, lanthanum oxide. Read-across to this structurally similar substance, lanthanum oxide, is justified on the basis that ecotoxicological effects will be driven by the metal cation species (La3+) which is analogous to the registered substance and the read-across substance. The similar toxicological profiles of lanthanum oxide and lanthanum trihydroxide further substantiates this to be an acceptable read-across approach. The study was performed in line with a recognised OECD guideline and has been assigned a score of 2 in line with the reliability scoring system of Klimisch et al (1997). Although the study was not conducted to GLP, the data are available and, since the study was well reported and performed to a standardised guideline, it was not deemed necesarry to repeat this vertebrate animal study.