Praseodymium trinitrate

Short-term toxicity to fish

Administrative data

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1997-03-24 - 1997-03-28

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

significant methodological deficiencies

Remarks:

No analytical monitoring was performed to investigate the stability of the test item in the test media. Precipitation of Pr may have occurred; which could have led to an underestimation of the ecotoxicity. Therefore, the results should not be considered entirely reliable. However, as relatively important adverse effects were observed in this study underestimating toxicity, it may be used as supporting study.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1997

Report date:

1997

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Praseodymium trinitrate

EC Number:

233-796-5

EC Name:

Praseodymium trinitrate

Cas Number:

10361-80-5

Molecular formula:

HNO3.1/3Pr

IUPAC Name:

praseodymium trinitrate

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Details on test solutions:

- stock solutions of approximately 0.01, 0.1, and 1 % were prepared each day by dissolving the test substance directly into distilled water
- test solutions were prepared by adding proper amounts of a stock solution and dilute further with dilution water to obtain the test concentrations
- for the preparation it was taken into account that the substance is an aqueous solution with approximately 55 % of praseodymium nitrate

Test organisms

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

- Common name: rainbow trout
- Strain: Walbaum
- Source: fish culture of Roger TEPPE, 01310 Polliat
- Age at study initiation (mean and range, SD): not reported
- Length at study initiation (length definition, mean, range and SD): 4.5 ± 0.6 cm
- Weight at study initiation (mean and range, SD): 0.91 ± 0.40 g
- Method of breeding: not reported
- Feeding during test: no

ACCLIMATION
- Acclimation period: 24 hours prior to start of test, selected fish were kept starved and placed in new aquaria
- Acclimation conditions (same as test or not): yes, same as test

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Test conditions

Hardness:

110-140 ppm as CaCO3

Test temperature:

15.3 ± 1°C

pH:

6.9-8.2

Dissolved oxygen:

65-90%

Salinity:

Not applicable.

Nominal and measured concentrations:

Nominal concentrations range-finding test 1: 1.0, 10 and 100 mg/L
Nominal concentrations definitive test 2: 0.10, 0.32, 1.0, 3.2, 10, 32 and 100 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: aquarium
- Material, size, headspace, fill volume: glass, 28 cm x 28 cm x 28 cm, headspace not reported, fill volume 15 L
- Aeration: not reported
- Renewal rate of test solution (frequency/flow rate): after 24h, 48h and 72h living fish were transferred to fresh aquaria (with test solution or dilution water for the treatment and blanc fish respectively), while dead fish were removed
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: potable water, stabilised, dechlorinated by aeration

OTHER TEST CONDITIONS
- Adjustment of pH: not reported
- Photoperiod: 12:12 hours dark:light
- Light intensity: 1000 - 2000 lux at water surface

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): mortality, after 3 hours and then daily

TEST CONCENTRATIONS
- Range finding study
* Test concentrations: 1, 10, and 100 mg/L.
- Results used to determine the conditions for the definitive study: Mortality was observed at the three concentrations tested during the range finder (1 mg/L; 40% mortality, 10 mg/L: 60%, 100 mg/L: 100%)

Reference substance (positive control):

yes

Remarks:

lindane

Results and discussion

Effect concentrations

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

0.71 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: CI. 0.22-1.7 mg/L

Details on results:

- LC50(24h) = 31 mg/L, 95 % C.I. 18 - 51 mg/L
- LC50(48h) = 16 mg/L, 95 % C.I. 1.0 - 32 mg/L
- LC50(72h) = 2.3 mg/L, 95 % C.I. 1.0 - 4.6 mg/L

Results with reference substance (positive control):

- LC50(24h) = 0.048 mg/L, 95 % C.I. 0.041 - 0.056 mg/L

Reported statistics and error estimates:

Probit analysis.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

This study reported an LC50 of 0.71 mg/L for Onchorhynchus mykiss after a 96-h exposure to praseodymium nitrate. The results cannot be considered entirely reliable as the test concentrations were not analytically verified and as precipitation may have occurred; which could have led to an underestimation of toxicity.