Rubidium nitrate

Endpoint summary

Description of key information

For oral acute toxicity endpoint, studies coming from the public domain have been used to fulfil the requirement.

- Khamidulina (1987 - Russian paper) is reporting a LD50 for rubidium nitrate of 4625 mg/kg bw. Khamidulina (1987) is also reporting the following values for other rubidium salts, these values are:

- Rubidium carbonate (CAS 584 -09 -8) - LD50 (oral, rat) 2625 mg/kg

- Rubidium chloride (CAS 7791 -11 -9) - LD50 (oral, rat) 5000 mg/kg

- Rubidium hydroxide (CAS 1310 -82 -3) - LD50 (oral, rat) 1650 mg/kg* !! alkaline effect!!

- Rubidium sulfate (CAS 7488 -54 -2) - LD50 (oral, rat) 4594 mg/kg

As weight of evidence with Rubidium salts, other values have been reported.

- Johnson et al. (1975) has reported an acute oral LD50 for Rubidium iodide in albino rats of 4708 mg/kg bw.

another publication prepared by FS Wagner 2011 (Encyclopedia) has also reported values for different rubidium salts:

- Rubidium carbonate (CAS 584 -09 -8) - LD50 (oral, rat) 2625 mg/kg

- Rubidium chloride (CAS 7791 -11 -9) - LD50 (oral, rat) 4040 mg/kg

- Rubidium hydroxide (CAS 1310 -82 -3) - LD50 (oral, rat) 586 mg/kg* !! alkaline effect!!

- Rubidium iodide (CAS 7790 -29 -6) - LD50 (oral, rat) 4708 mg/kg

- Rubidium sulfate (CAS 7488 -54 -2) - LD50 (oral, rat) 4594 mg/kg

According the data found in the literature, we can conclude that rubidium salts including rubidium nitrate is considered as NOT toxic regarding acute oral toxicity. It has to be noted that the LD50 oral acute on rats made with rubidium hydroxide has been disregarded as the adverse effects is induced by the hydroxide.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Reference 1

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

Not applicable - Publication 1987

Reliability:

other: Paper written in Russian

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Version / remarks:

Paper published and written in russian

Principles of method if other than guideline:

Paper written in Russian

GLP compliance:

not specified

Remarks:

Paper written in Russian

Test type:

acute toxic class method

Specific details on test material used for the study:

Paper written in Russian

Species:

rat

Details on test animals or test system and environmental conditions:

Paper written in Russian

Route of administration:

oral: gavage

Key result

Effect level:

ca. 4 625 mg/kg bw

Based on:

test mat.

Remarks:

Rubidium nitrate

Remarks on result:

other: Paper written in Russian

Effect level:

ca. 1 650 mg/kg bw

Based on:

test mat.

Remarks:

Rubidium hydroxide

Remarks on result:

other: Paper written in Russian

Effect level:

ca. 4 594 mg/kg bw

Based on:

test mat.

Remarks:

Rubidium sulfate

Remarks on result:

other: Paper written in Russian

Effect level:

ca. 5 000 mg/kg bw

Based on:

test mat.

Remarks:

Rubidium chloride

Remarks on result:

other: Paper written in Russian

Interpretation of results:

GHS criteria not met

Conclusions:

A russian study has reported acute oral toxicity on rat. The LD50 of rubidium nitrate was 4625 mg/kg bw. (Paper available in Russian, only)

Reference 2

Endpoint:

acute toxicity: oral

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Study period:

no data

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: No GLP, equivalent or similar to OECD and EU guideline.

Justification for type of information:

Rubidium nitrate (CAS no. 13126-12-0, EC no. 236-060-1)

Rubidium (Rb+) is an alkali metal which belongs to Group 1 of the periodic table sharing comparable physical and chemical properties with other Group 1 elements, including lithium, sodium, potassium, cesium and francium.
Therefore, accumulation and excretion of rubidium is similar to potassium, such that body K+ appears to be a reliable index to estimate retention of Rb+. Physiological similarity of rubidium and potassium was reported by the team of Relman AS in the sixties. In fact, Rb+ follows the movement of K+ in the body and competes with K+ for transport across cell membranes. Physiological experiments indicate exchangeability of rubidium for potassium in blood, plasma, and tissue (Relman AS, 1956).
Medical and toxicological literatures generally indicate a very low degree of toxicity (Johnson et al., 1975; Khamidulina, 1987; Wagner, 2011). In many cases, the health risks of rubidium compounds are associated with the anion, e.g., hydroxide, or fluoride, rather than the rubidium cation.

Literature
Hall PWH and Relman AS. 1960. Acid excretion in rubidium- and cesium-substituted rats. J Clin Invest. 39:171–177.
Johnson GT, Lewis RT, Wagner WD. 1975. Acute toxicity of cesium and rubidium compounds. Toxicol App Pharmacol. 32:239-245.
Khamidulina Kh. Kh. 1987. Gig. Tr. Prof. Zabol. (9), 55 (Russian paper)
Relman AS, Roy AM, Schwartz. 1955. The acidifying effect of Rubidium in normal and potassium-deficient alkalotic rats. J Clin Invest. 34: 538–544.
Relman AS. 1956. The physiological behaviour of Rubidium and Cesium in relation to that of potassium. Yale J Biol Med. 29:248-62.
Wagner FS. 2011. Rubidium and Rubidium Compounds. Kirk-Othmer Encyclopedia of Chemical Technology. John Wiley & Sons, Inc.

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Deviations:

not specified

Remarks:

, e.g. 9 instead of 10 animals

Qualifier:

equivalent or similar to guideline

Guideline:

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

Deviations:

not specified

Remarks:

, e.g. 9 instead of 10 animals

GLP compliance:

no

Test type:

standard acute method

Limit test:

no

Specific details on test material used for the study:

High purity material in excess of 99%

Species:

rat

Strain:

other: Charles River albino rats

Sex:

male

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River, cesarian-derived albino rats
- Weight at study initiation: 175 -250 g
- Fasting period before study: yes (overnight, 16 h)

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

VEHICLE
- Justification for choice of vehicle: good solubility in water

Doses:

First main test: 820, 1170, 1660, 2350, 3340, 4750 mg/kg
Second main test: 1890, 2120, 2515, 2680, 3010 mg/kg

No. of animals per sex per dose:

9 male rats

Control animals:

not specified

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: 1 and 4 h following administration and dayly thereafter for the 14-day period
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, histopathology, behavioral observations

Statistics:

The LD50 values and their 95% confidence limits were calculated by probit analysis of Finney (1971).

Preliminary study:

not applicable; however, range finding study was performed:
The test material was administered as a single dose, orally by stomach tube, to caesarean-derived rats weighing between 175 and 250 grams. Eight test groups of three animals per group (24 total) were used. The animals were fasted from food for approximately 16 hours prior to dosing. The test material was dissolved in deionized and distilled water. Observations for morbidity and mortality were recorded at 1 and 4 hours following administration and daily thereafter for the 7-day period. Gross necropsy observations were made on all animals which died or were sacrificed at the end of the 7-day observation period.

Key result

Sex:

male

Dose descriptor:

LD50

Effect level:

4 708 mg/kg bw

Based on:

test mat.

Remarks:

RbI

95% CL:

ca. 4 413 - ca. 5 026

Mortality:

yes. All deaths occured within the first 72 hr after dosing.

Body weight:

No data on body weight.

Other findings:

The most notable necropsy findings in rats that died following the administration of RbI were congested, cyanotic lungs with petechial hemorrhages and fluid-distended stomach which appeared to result from spasm of the pyloric sphincter following the dosing. All deaths occured within the first 72 hr after dosing.

Interpretation of results:

not classified

Conclusions:

The acute oral LD50 of Rubidium iodide in albino rats was determined to be 4708 mg/kg bw.

Executive summary:

In an acute oral toxicity study, groups of 9 fasted male albino rats were given a single oral dose of Rubidium iodide (> 99 %) in water at 11 different doses and observed for 14 days.

Oral LD50 Males = 4708 mg/kg bw (95% C.L: 4413 - 5026 mg/kg)

Rubidium iodide is not classified after oral administration based on the LD50 obtained in male rats.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

4 625 mg/kg bw

Quality of whole database:

Data coming from the public domain.