Dirhodium trioxide

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to aquatic invertebrates

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because the substance is highly insoluble in water, hence indicating that aquatic toxicity is unlikely to occur

Justification for type of information:

no experimental study is required for dirhodium trioxide based on the outcome of a full TDp assay (cfr. IUCLID Section 4 'Water solubility') and the identified acute and chronic threshold values with water soluble rhodium(III) substances.

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

no

Analytical monitoring:

yes

Details on sampling:

Samples taken at the start and end of the test

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 (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.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

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

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

290 µg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

element

Basis for effect:

mobility

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.

Description of key information

no experimental study is required for dirhodium trioxide based on the outcome of a full TDp assay (cfr. IUCLID Section 4 'Water solubility') and the identified acute and chronic threshold values with water soluble rhodium(III) substances.

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

This is the lowest acute threshold identified with Rhodium(III) substances, and this value serves as basis for acute ERV derivation.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

290 µg/L

Additional information

no experimental study is required for dirhodium trioxide based on the outcome of a full TDp assay (cfr. IUCLID Section 4 'Water solubility') and the identified acute and chronic threshold values with water soluble rhodium(III) substances.

Okamoto et al. (2014) assessed the toxicity of 50 metals, including rhodium (as rhodium trichloride hydrate) toDaphnia 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.