Rhodium chloride (RhCl3), hydrate

Endpoint summary

Description of key information

In a guideline acute oral toxicity study, conducted to GLP, respective LD50 values of 753 and 1257 mg/kg bw were reported in female and male rats following gavage administration of rhodium trichloride (hydrate) (Mayr, 1986a).
The acute dermal LD50 of rhodium (III) chloride hydrate was found to exceed 2000 mg/kg bw following a 24-hour occlusive application in rabbits (Mayr, 1986b).
No relevant acute inhalation toxicity data were identified, or are required at this tonnage.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

8-24 April 1986

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study, to GLP. It should be noted that this record was produced using an English translation of the study report that was originally written in German.

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.1 (Acute Toxicity (Oral))

Deviations:

no

GLP compliance:

yes

Test type:

standard acute method

Limit test:

no

Species:

rat

Strain:

other: Wistar Bor: WISW

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Winkelmann Versuchstierzucht GmbH & Co. KG., D-4799 Borchen
- Age at study initiation: Males, 49-52 days; females, 63-65 days
- Weight at study initiation: Males, 128-154 g; females, 129-149 g
- Fasting period before study: 16 hr
- Housing: Individually housed in Macrolon cages, type II
- Diet (e.g. ad libitum): Standard diet ad libitum (ssniff (R), "Special diet for rats"; Fa. Ssniff Spezialfutter GmbH, D-4770 Soest)
- Water (e.g. ad libitum): Water was provided ad libitum in drinking water quality of the Stadtwerke Bielefeld (Municipal Works)
- Acclimation period: At least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 1
- Humidity (%): 50 ± 10
- Air changes (per hr): No data
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: No data

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 215 mg/mL
- Amount of vehicle (if gavage): 2.15, 3.16, 4.64 and 10.0 mL/kg bw
- Justification for choice of vehicle: Not applicable
- Lot/batch no. (if required): Not applicable
- Purity: Aqueous solution

MAXIMUM DOSE VOLUME APPLIED: 2150 mg/kg bw

DOSAGE PREPARATION (if unusual): Not applicable

Doses:

464, 681, 1000, or 2150 mg/kg bw

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: The animals were observed for the first 6-8 hrs after dosing and were then checked once-twice daily. Animals were weighed weekly on days 0, 7 and 14 of the study
- Necropsy of survivors performed: yes (Gross necropsy was performed on all animals that died during the course of the study and on surviving animals that were killed at the end of the 14-day observation period. External appearance, body orifices, body cavities (thoracic and abdominal) and their contents were examined macroscopically)
- Other examinations performed: clinical signs, body weight

Statistics:

Data was evaluated by probit analysis with a confidence limit of 95%

Sex:

female

Dose descriptor:

LD50

Effect level:

753 mg/kg bw

Based on:

test mat.

95% CL:

>= 536 - <= 3 984

Sex:

male

Dose descriptor:

LD50

Effect level:

1 257 mg/kg bw

Based on:

test mat.

95% CL:

>= 798 - <= 1 981

Mortality:

No deaths were seen in either male or female rats treated at the 464 mg/kg bw dose level. At the 681 mg/kg bw dose level, one female and one male died one and five days after administration respectively. Two males treated at 1000 mg/kg bw died 2 days after treatment, while all five females died between one and three days after treatment at this dose. At the highest tested dose level of 2150 mg/kg bw, all animals died three to six hours after treatment. The remaining animals survived the 14-day observation period.

Clinical signs:

other: No signs of toxicity were observed in any animals treated at the lowest dose level. The clinical signs observed at dose levels of 681 mg/kg bw and above included ataxia, piloerection and decreased muscle tone as well as a general loss of reflexes. Tremo

Gross pathology:

Necropsy of the dead animals revealed reddened mucous membrane of the stomach and intestine and yellow coloured mucous membrane of the intestine resp.. [the gross necropsy is not well reported – possibly due to a poor translation] {no further details discernible from the translated report}

Other findings:

No data

The study authors note “a stronger sensitivity of the females could be derived numerically, no sex specific reaction is presumed under consideration of the mortality data and the confidence limits".

Interpretation of results:

Toxicity Category IV

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

In a guideline acute oral toxicity study, conducted to GLP, respective LD50 values of 753 mg/kg bw (536-3984 mg/kg bw, 95% confidence limit) and 1257 mg/kg bw (798-1981 mg/kg bw, 95% confidence limit) were reported in female and male rats following gavage administration of rhodium (III) chloride (hydrate), and observation for up to 14 days.

Executive summary:

In a standard acute oral toxicity study (conducted to OECD guideline 401 and to GLP), groups of five male and five female rats were administered 464, 681, 1000 on 2150 mg/kg bw of rhodium (III) chloride (hydrate) by stomach tube and observed for 14 days.

All animals in the top dose level as well as 2 males and 5 females given 1000 mg/kg bw died. No mortality was observed at the lowest dose and only a single male and female given 681 mg/kg bw died. Clinical signs of toxicity appeared one hour following administration. The surviving animals did not show any signs of toxicity. Reduced body weight was observed in one female treated at the 681 mg/kg bw dose level. A number of clinical signs were apparent at this dose level and above. Using the prescribed statistical method, the acute oral median lethal dose (LD50) and 95% confidence limits were found to be 1257 (798-1981) mg/kg bw for males and 753 (536-3984) mg/kg bw for females.

Based on the results of this study, rhodium trichloride (hydrate) should be classified for acute oral toxicity (category 4) according to EU CLP criteria (EC 1272/2008).

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

753 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

11 March - 30 April 1986

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study, to GLP. It should be noted that this record was produced using an English translation of the study report that was written in German.

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.3 (Acute Toxicity (Dermal))

Deviations:

no

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Species:

rabbit

Strain:

New Zealand White

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Savo Ivanovas med. , Versuchstierzuchten GmbH, D-7940 Kisslegg im Allgäu
- Age at study initiation: Males, 3-4 months; females, 2-4 months
- Weight at study initiation: Males, 2.75-3.00 kg; females, 2.15-2.75 kg
- Fasting period before study: On the day of treatment
- Housing: Individually housed in high-grade steel cages
- Diet (e.g. ad libitum): Ad libitum standard diet, ssniff K “special diet for rabbits” supplied by ssniff Spezialfutter GmbH, D-4770 Soest
- Water (e.g. ad libitum): Ad libitum
- Acclimation period: Animals kept for 5 days under test conditions before application of the test material

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22.5-23.5
- Humidity (%): 45-60
- Air changes (per hr): No data
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: No data

Type of coverage:

occlusive

Vehicle:

water

Remarks:

moistened with water

Details on dermal exposure:

TEST SITE
- Area of exposure: No data
- % coverage: No data
- Type of wrap if used: No data

REMOVAL OF TEST SUBSTANCE
- Washing (if done): yes, washed off with water
- Time after start of exposure: 24 hrs

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): No data
- Concentration (if solution): Not applicable
- Constant volume or concentration used: Not applicable

VEHICLE
- Amount(s) applied (volume or weight with unit): Not applicable
- Concentration (if solution): Not applicable
- Purity: Not applicable

Duration of exposure:

24 hours

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

5 male and 3 female

Control animals:

no

Details on study design:

- Duration of observation period following administration: 21-27 days
- Frequency of observations and weighing: Observations 6-8 hours after application, then twice daily (once daily at weekends), body weights measured directly before, and 7 and 14 days after, application.
- Necropsy of survivors performed: Yes (Gross necropsy was performed on all animals that died during the course of the study and on surviving animals that were killed at the end of the observation period. External appearance, body orifices, body cavities (thoracic and abdominal) and their contents were examined macroscopically)
- Other examinations performed: Clinical signs, body weight

Statistics:

Not applicable (Limit test acute dermal LD50)

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

One of the male rabbits died 3 days after application of the test material. No deaths were noted amongst the females.

Clinical signs:

other: One male was in poor general health (prior to death). No symptoms in the remaining animals.

Gross pathology:

In the male that died, observations included bleeding in the pelvic area and brittle bones as well as liver and kidney damage. Two hours after death, the blood still showed no tendency to coagulate.

Other findings:

No data

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

In a guideline acute dermal toxicity study, conducted to GLP, the median lethal dose (LD50) of rhodium (III) chloride hydrate was found to exceed 2000 mg/kg bw following a 24-hour occlusive application in rabbits.

Executive summary:

In an acute dermal limit test, conducted according to OECD Test guideline 402 and to GLP, 5 male and 3 female New Zealand White rabbits received a single dermal application of rhodium (III) chloride hydrate (moistened with water) at 2000 mg/kg bw for 24 hours (under occlusion).

 

A single male died at this dose 3 days after application, exhibiting reduced body weight as well as effects on the liver, kidney and blood. No toxicity was apparent in the remaining animals. The acute dermal median lethal dose (LD50) of rhodium (III) chloride hydrate is greater than 2000 mg/kg bw in rabbits.

 

Based on the results of this study, rhodium (III) chloride hydrate does not need classification for acute dermal toxicity according to EU CLP criteria (EC 1272/2008).

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Additional information

No relevant acute toxicity human data were identified.

In a standard acute oral toxicity study (conducted to OECD guideline 401 and to GLP), groups of five male and five female rats were administered 464, 681, 1000 on 2150 mg/kg bw of rhodium trichloride (hydrate) by stomach tube and observed for 14 days. All animals in the top dose level as well as 2 males and 5 females given 1000 mg/kg bw died. No mortality was observed at the lowest dose and only a single male and female given 681 mg/kg bw died. Clinical signs of toxicity appeared one hour following administration. The surviving animals did not show any signs of toxicity. Reduced body weight was observed in one female treated at the 681 mg/kg bw dose level. A number of clinical signs were apparent at this dose level and above. Using the prescribed statistical method, the acute oral median lethal dose (LD50) and 95% confidence limits were found to be 1257 (798-1981) mg/kg bw for males and 753 (536-3984) mg/kg bw for females (Mayr, 1986a).

 

In an acute dermal limit test, conducted according to OECD Test guideline 402 and to GLP, 5 male and 3 female New Zealand White rabbits received a single dermal application of rhodium (III) chloride hydrate (moistened with water) at 2000 mg/kg bw for 24 hours (under occlusion). A single male died at this dose 3 days after application, exhibiting reduced body weight as well as effects on the liver, kidney and blood. No toxicity was apparent in the remaining animals. The acute dermal LD50 was determined to exceed 2000 mg/kg bw (Mayr, 1986b).

 

No acute inhalation toxicity data were identified, or are required at this tonnage (1-10 tpa).

Justification for selection of acute toxicity – oral endpoint
OECD guideline study, and the only acute oral toxicity study available.

Justification for selection of acute toxicity – dermal endpoint
OECD guideline study, and the only acute oral toxicity study available.

Justification for classification or non-classification

Based on the results of the available and reliable acute oral study in rats, rhodium trichloride (hydrate) should be classified for acute oral toxicity (category 4) according to EU CLP criteria (EC 1272/2008).

 

Based on the results of the available and reliable acute dermal study in rats, rhodium trichloride (hydrate) does not require classification for acute dermal toxicity according to EU CLP criteria (EC 1272/2008).

 

No clear evidence of specific target organ toxicity was noted. As such, classification for STOT-SE is not considered appropriate.