Rhodium acetate

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference

Reference Type:

publication

Title:

Acute toxicity of 50 metals to Daphnia magna

Author:

Okamoto A, Yamamuro M, Tatarazako N

Year:

2014

Bibliographic source:

J. Appl. Toxicol. 35:824-830

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Rhodium chloride (RhCl3), hydrate

EC Number:

606-630-8

Cas Number:

20765-98-4

Molecular formula:

RhCl3.3(H2O)

IUPAC Name:

Rhodium chloride (RhCl3), hydrate

Details on test material:

95% pure

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Samples taken at the start and end of the test

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Stock solution made up in distilled water then added to breeding water for the experiments
- Differential loading: Five test concentrations, dilution factor of 2
- Controls: Control consisted of breeding water only

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Source: National Institute for Environmental Studies, Tsukubi, Japan


CULTURE CONDITIONS
- Water temperature for breeding 21 +- 1°C, light: dark cycle 16:8h. Breeding conducted in glass flasks, 35 adults per litre. Female neonates <24h were subcultured every week. Breeding water was tap water filtered with activated charcoal. Chlorella vulgaris used as food source during culturing.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Test temperature:

21 +- 1°C

pH:

6.5 - 8.5

Salinity:

Not applicable

Nominal and measured concentrations:

Five test concentrations with a dilution factor of 2. Measured concentrations used for reporting of results.

Details on test conditions:

Photoperiod: 16:8 light:dark cycle
pH was adjusted using 1 N sodium hydroxide

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

290 µg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

element

Basis for effect:

mobility

Applicant's summary and conclusion

Conclusions:

The 48-hour EC50 for Daphnia magna was 290 µg Rh L-1.

Executive summary:

Okamoto et al. (2014) assessed the toxicity of 50 metals, including rhodium (as rhodium trichloride hydrate) to Daphnia magna. The study followed OECD guideline 202, with 5 test concentrations included and a spacing factor of 2. pH of the test solutions was adjusted using sodium hydroxide. Test concentrations were analysed using ICP-MS and results reported based on measured values. The study is assigned a Klimisch score of 2 (reliable with restrictions) as it followed a standard test guideline, but is not GLP compliant and as a number of metals were tested in the same study some of the method details and the individual data for each metal are not reported. The 48-hour EC50 for Daphnia magna was 290 µg Rh L-1.