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Toxicological information

Acute Toxicity: oral

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Administrative data

Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
Well documented, scientifically sound study with methods similar to OECD 401 with the following deviations: The number of deaths at each dose were not reported; the specific doses (mg/kg) were not provided; individual clinical observations, body weights, pathology were not reported; sex of the animals was not provided

Data source

Reference
Reference Type:
publication
Title:
Acute Toxicity of Zirconium, Columbium, Strontium, Lanthanum, Cesium, Tantalum, and Yttrium
Author:
Cochran KW, Doull J, Mazur M, DuBois KP
Year:
1950
Bibliographic source:
Industrial Hygiene and Occupational Medicine 1: 637-650,

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 401 (Acute Oral Toxicity)
Deviations:
yes
Remarks:
The number of deaths at each dose were not reported; the specific doses (mg/kg) were not provided; individual clinical observations, body weights, pathology were not reported; sex of the animals was not provided
GLP compliance:
no
Test type:
standard acute method
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Lanthanum acetate

Test animals

Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: no data
- Age at study initiation: adult
- Weight at study initiation: between 200 and 300 g
- Fasting period before study: no data
- Housing: no data
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: no data

ENVIRONMENTAL CONDITIONS
Animals were maintained in air conditioned rooms.

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
water
Details on oral exposure:
VEHICLE
- Concentration in vehicle: 50% suspension

Doses:
The suspension was given in single doses by stomach tube. No further information on doses provided.
No. of animals per sex per dose:
32 rats in total
Control animals:
not specified
Details on study design:
- Duration of observation period following administration: All animals were observed for 10 days. An initial group of animals receiving the test substance were kept for 30 days to verify that if any significant mortality occurred after the tenth day.
- Frequency of observations and weighing: no data
- Necropsy of survivors performed: no data
Statistics:
The LD50 values were obtained from ten day mortality data by using the log-probability method.

Results and discussion

Effect levels
Sex:
male/female
Dose descriptor:
LD50
Effect level:
10 000 mg/kg bw
Based on:
test mat.
Remarks on result:
other: i.e. 4400 mg La/kg bw
Mortality:
No further details reported. No sex differences were noted.
Clinical signs:
No further details reported except that lanthanum acetate was found to be the least toxic of several lanthanum compounds tested (lanthanum chloride, lanthanum ammonium nitrate, lanthanum nitrate, lanthanum oxide and lanthanum sulfate.
Body weight:
No data
Gross pathology:
No data

Applicant's summary and conclusion

Interpretation of results:
not classified
Remarks:
Migrated information Criteria used for interpretation of results: EU
Conclusions:
The oral LD50 was calculated to be 10000 mg compound/kg bw (i.e. 4400 mg La/kg bw)