Reaction mass of cerium dioxide and lanthanum oxide and lanthanum fluoride

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 17-JAN-1980 to 01-FEB-1980

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study conducted according to basic scientific principles (Draize test) but none information were missing on materials and methods and test substance purity.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1980

Report date:

1980

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: Draize test

Deviations:

not specified

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Reference substance 001

EC Number:

909-701-4

Molecular formula:

(Ce (1-x)Lax)OyFz

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: no data
- Age at study initiation: no data
- Weight at study initiation: 2.5-3.5 kg
- Housing:no data
- Diet (e.g. ad libitum): no data
- Water (e.g. ad libitum): no data
- Acclimation period: no data


ENVIRONMENTAL CONDITIONS
- Temperature (°C): no data
- Humidity (%): no data
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): no data


IN-LIFE DATES: skin treatment on 24 january 1980

Test system

Type of coverage:

occlusive

Preparation of test site:

other: shaved site and abraded site

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit):0.5 g
- Concentration (if solution): not applicable


VEHICLE: not applicable (test substance powder applied as supplied)

Duration of treatment / exposure:

24-hour exposure period

Observation period:

25 hours (one hour after dressing removal) and 72 hours after application.

Number of animals:

6 rabbits

Details on study design:

TEST SITE
- Area of exposure: 3 cm diameter
- % coverage: no data
- Type of wrap if used: trunk bandage.


REMOVAL OF TEST SUBSTANCE
- Washing (if done): no
- Time after start of exposure: 24 hours


SCORING SYSTEM: Draize scale

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

primary dermal irritation index (PDII)

Remarks:

intact skin

Basis:

mean

Remarks:

25 + 72 hours (erythema + oedema)

Time point:

other: 25 + 72 hours

Score:

0

Max. score:

12

Reversibility:

other: not relevant because no effect

Results 2

Irritation parameter:

primary dermal irritation index (PDII)

Remarks:

abraded skin

Basis:

mean

Remarks:

25 + 72 hours (erythema +oedema)

Time point:

other: 25 + 72 hours

Score:

0.08

Max. score:

12

Reversibility:

fully reversible within: 72 hours

Any other information on results incl. tables

Irritant/corrosive response data for each animal at each observation time up to removal of each animal from the test for intact skin:

Score at time point / Reversibility	Erythema	Edema
	Max. score: 4	Max. score: 4
25 h	0/0/0/0/0/0	0/0/0/0/0/0
48 h	-	-
72 h	0/0/0/0/0/0	0/0/0/0/0/0
Average 25h to 72h	0.00	0.00
Reversibility*	-	-
Average time (unit) for reversion	-	-

* Reversibility: c. = completely reversible; n.c. = not completely reversible; n. = not reversible

Irritant/corrosive response data for each animal at each observation time up to removal of each animal from the test for abraded skin:

Score at time point / Reversibility	Erythema	Edema
	Max. score: 4	Max. score: 4
25 h	0/0/0/0/1/1	0/0/0/0/0/0
48 h	-	-
72 h	0/0/0/0/0/0	0/0/0/0/0/0
Average 25h to 72h	0.33	0.00
Reversibility*	c	-
Average time (unit) for reversion	-	-

*Reversibility: c. = completely reversible; n.c. = not completely reversible; n. = not reversible

For the abraded skin, erythema (grade 1) was observed in 2/6 animals at 25 hours and reversed by 72 hours; no oedema was noted at any time in any rabbit.

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The reaction mass of Cerium dioxide and Lanthanum oxide and Lanthanum fluoride is not irritant to the skin and not classified as such according to Annex VI of the Directive 67/548/CEE and according to EU Regulation 1272/2008 (CLP).

Executive summary:

The reaction mass of Cerium dioxide and Lanthanum oxide and Lanthanum fluoride has been tested for skin irritation on 6 New Zealand albino rabbits according to DRAIZE method. The rabbits received a dermal dose of 0.5 g of reaction mass of Cerium dioxide and Lanthanum oxide and Lanthanum fluoride (put on moistened gauze with 0.5 ml water) on intact and abraded skin sites under an occlusive dressing for a period of 24 hours. Scores for erythema and oedema were measured 1 and 48 hours after patch removal and primary cutaneous index was calculated (maximum possible index =12)

 

No sign of dermal irritation (score = 0 for erythema and oedema) was observed for intact skin site of the 6 rabbits at both reading times while a slight erythema (score 1) but no oedema (score 0) was observed in 2/6 animals 1 hour after patch removal for the abraded skin site. Forty eight hours after patch removal, scores for erythema and oedema both return to 0 for the abraded skin sites in all animals. Primary Irritation Index was 0.08.

 

The reaction mass of Cerium dioxide and Lanthanum oxide and Lanthanum fluoride is not classified irritating to skin according to the criteria of the Directive 67/548/CEE and according to EU Regulation 1272/2008 (CLP).