Reaction mass of cerium phosphate and lanthanum phosphate and terbium phosphate

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from 01-JUNE-2007 to 21-NOV-2007

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was performed according to EU / OECD guidelines and GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2007

Report date:

2007

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

no

Test guideline 2

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

Test material

Test material information

Constituent 1

Reference substance name:

cerium(3+) lanthanum(3+) terbium(3+) triphosphate

EC Number:

915-152-1

Molecular formula:

(La,Ce,Tb)PO4

IUPAC Name:

cerium(3+) lanthanum(3+) terbium(3+) triphosphate

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS:
- Source: Janvier, Le Genest-Saint-Isle, France.
- Age at study initiation: approximately 8 weeks old
- Weight at study initiation: 341 ± 11 g for the males and 217 ± 9 g for the females.
- Fasting period before study: data not available
- Housing: housed individually in polycarbonate cages with stainless steel lid (35.5 cm x 23.5 cm x 19.3 cm)
- Diet: free access to SsniffR/M-H pelleted diet (SSNIFF Spezialdiäten GmbH, Soest, Germany)
- Water: drinking water filtered by a FG Millipore membrane (0.22 micron) was provided ad libitum
- Acclimation period: at least 5 days before the beginning of the study

* Environmental conditions:
- Temperature: 22 ± 2°C
- Humidity: 30 to 70%
- Air changes: approximately 12 cycles/hour of filtered, non-recycled air
- Photoperiod: 12 h dark/12 h light

* In-life dates : From: 07-JUNE-2007 To: 21-JUNE-2007

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

other: none

Details on dermal exposure:

* Test site:
- Area of exposure: dorsal area, approximately 5 cm x 7 cm for males and 5 cm x 6 cm for females
- % coverage: approximately 10% of the total body surface of the animals
- Type of wrap if used: gauze pad held in contact by means of an adhesive hypoallergenic aerated semi-occlusive dressing and a restraining bandage

* Removal of test substance:
- Washing (if done): On removal of the dressing, any residual test item was removed using a moistened cotton pad.
- Time after start of exposure: 24 hours

* Test material:
- Amount(s) applied: 2000 mg/kg bw
- Concentration (if solution): not applicable
- Constant volume or concentration used: yes
- For solids, paste formed: yes (moistened with 2 ml of purified water)

* Vehicle:
- Amount(s) applied: no
- Concentration (if solution): not applicable

Duration of exposure:

24 hours

Doses:

2000 mg/lg bw

No. of animals per sex per dose:

5 males and 5 females

Control animals:

not required

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing:
> Clinical signs and mortality: frequently during the hours following administration of the test item. Thereafter, observation of the animals was made at least once a day until day 15.
> Body weight: just before administration of the test item on day 1 and then on days 8 and 15.
- Necropsy of survivors performed: yes (digestive tract, heart, kidneys, liver, lungs, pancreas, spleen and any other organs with obvious abnormalities)
- Other examinations performed: local cutaneous reactions at application site were recorded from day 2.

Statistics:

not applicable

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Mortality:

No deaths occurred during the study.

Clinical signs:

other: No clinical signs and no cutaneous reactions at the treatment site were observed during the study.

Gross pathology:

Macroscopic examination of the main organs of the animals revealed no apparent abnormalities.

Other findings:

no other information

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Under the experimental conditions of this study, the dermal LD50 of the test item Reaction mass of lanthanum phosphate and cerium phosphate and terbium phosphate was higher than 2000 mg/kg in rats.

Executive summary:

The acute dermal toxicity of the test item Reaction mass of lanthanum phosphate and cerium phosphate and terbium phosphate was evaluated in rats according to OECD (No. 402, 24th February 1987) and EC (92/69/EEC, B.3, 31st July 1992) guidelines. The study was conducted in compliance with the principles of Good Laboratory Practice Regulations.

The test item was applied to the skin of one group of ten Sprague-Dawley rats (five males and five females).

The application was performed with the test item in its original form (moistened with 2 ml of purified water) at the dose-level of 2000 mg/kg. The test site was then covered by a semi-occlusive dressing for 24 hours. Clinical signs, mortality and body weight gain were checked for a period of 14 days following the single application of the test item. All animals were subjected to necropsy.

No deaths, no clinical signs and no cutaneous reactions at the treatment site were observed during the study. When compared to CIT historical control animals, a slightly lower body weight gain was noted in 1/5 females between day 1 and day 8, without any relevant consequence at the end of the observation period. The overall body weight gain of the other animals was not affected by treatment with the test item. No apparent abnormalities were observed at necropsy in any animal.

Under the experimental conditions of this study, the dermal LD50 of the test item Reaction mass of lanthanum phosphate and cerium phosphate and terbium phosphate was higher than 2000 mg/kg in rats.

This acute dermal study is classified as acceptable. It does satisfy the guideline requirement for an acute dermal study (EU B.3) in the rats.