Barium oxide, obtained by calcining witherite

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

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

Adequacy of study:

weight of evidence

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: Read-across from barium chloride for barium toxicity. Study does not give information on the dose levels tested and the mortality rates at different dosages.

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

publication

Title:

Subchronic Oral Toxicity of BaCl2 in Rats

Author:

Tardiff et al

Year:

1980

Bibliographic source:

Journal of Environmental Pathology and Toxicology, 4:267-275

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Principles of method if other than guideline:

no specification of dose levels, no data on fasting of animals prior to compound administration, no data on clinical examinations or necropsy results, no specification of mortality at different dose levels

GLP compliance:

not specified

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Barium chloride

EC Number:

233-788-1

EC Name:

Barium chloride

Cas Number:

10361-37-2

IUPAC Name:

barium dichloride

Details on test material:

- Name of test material (as cited in study report): Barium Chloride
- Molecular formula (if other than submission substance): BaCl2
- Physical state: solid
- Analytical purity: at least 98%
- Impurities (identity and concentrations): no data

Test animals

Species:

rat

Strain:

not specified

Sex:

male/female

Details on test animals or test system and environmental conditions:

rats were used both as weanlings (21-25 days of age) and as adults (60-70 days)

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Doses:

8 doses (concentrations of compound were not specified) were administered as single doses by gavage

No. of animals per sex per dose:

10 animals per dose level

Control animals:

not specified

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: no data
- Necropsy of survivors performed: no data

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

132 mg/kg bw

Based on:

test mat.

95% CL:

112.2 - 162.36

Remarks on result:

other: LD50 and 95% CL were calculated for Barium

Any other information on results incl. tables

LD50 for weanling rats was higher than for adults (220 mg Barium/kg, 95% CL 186,6 -264 and 132 mg Barium/kg, 95% CL 112.2 -162.4, respectively). No explanation for this finding was provided.

A dose-mortality curve was provided and showed a slope of 7.2 for adult animals and 6.2 for weanlings.

Applicant's summary and conclusion

Executive summary:

Although the study does not provide information on the dose levels tested and the mortalities at different dose levels, it can provide LD50 values with 95% confidence intervals and the slope of a dose-mortality curve. The data are in accordance with the literature (ref. Borzelleca et al., 1988), therefore the data provided is considered sufficient for proposal of classification.