lambda4-cerium(4+) zirconium(4+) tetraoxidandiide

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

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

Adequacy of study:

supporting study

Study period:

November 1982 - February 1983

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: OECD TG 404-compliant study

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1983

Report date:

1983

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Cerium dioxide

EC Number:

215-150-4

EC Name:

Cerium dioxide

Cas Number:

1306-38-3

Molecular formula:

CeO2

IUPAC Name:

cerium dioxide

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Roucher, Couhé France - EGAV, Passais-la-Conception France - Elevage Scientifique des Dombes, Châtillon-sur-Chalaronne France - Gwen Meur, Trégonneau France
- Age at study initiation: not specified
- Weight at study initiation: 2.5 kg +/- 200 g
- Housing: individual polystyrene cages (54 x 36 x 31.5 cm)
- Diet: 150 g pelleted diet/animal/day
- Water: ad libitum
- Acclimation period: at least 8 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 +/- 3
- Humidity (%): 50 +/- 20
- Air changes (per hr): 12
- Photoperiod (hrs dark / hrs light): 12 / 12 (7.30 am - 7.30 pm)


IN-LIFE DATES: 23 November 1982 (application)

Test system

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

other: moistening with 0.1 mL water

Controls:

not required

Amount / concentration applied:

TEST MATERIAL
- Amount applied: 0.5 g

Duration of treatment / exposure:

4 hours

Observation period:

14 days

Number of animals:

3 males

Details on study design:

TEST SITE
- Area of exposure: approximately 6 cm² skin surface
- Type of wrap: semiocclusive dressing


REMOVAL OF TEST SUBSTANCE
- Washing: yes
- Time after start of exposure: 4 hours


SCORING SYSTEM:
- Erythema and Eschar Formation:
No erythema -> 0
Very slight erythema (barely perceptible) ->1
Well defined erythema -> 2
Moderate to severe erythema -> 3
Severe erythema (beef redness) to eschar formation preventing grading of erythema -> 4

- Oedema Formation:
No oedema -> 0
Very slight oedema (barely perceptible) -> 1
Slight oedema (edges of area well defined by definite raising) -> 2
Moderate oedema (raised approximately 1 mm) -> 3
Severe oedema (raised more than 1 mm and extending beyond area of exposure) -> 4

- Primary Dermal Irritation Index = (Sum of individual Erythema scores + Sum of individual Edema scores) / 12

Results and discussion

In vivo

Results

Irritation parameter:

primary dermal irritation index (PDII)

Basis:

mean

Time point:

other: 1, 24, 48, 72 hours

Score:

0

Max. score:

8

Reversibility:

other: not applicable

Any other information on results incl. tables

Summary table of individual irritation scores:

Rabbit number		445	446	447	Total	Mean
Erythema score
Timepoints (h)	1	0	0	0	0	0
	24	0	0	0	0	0
	48	0	0	0	0	0
	72	0	0	0	0	0
Edema score
Timepoints (h)	1	0	0	0	0	0
	24	0	0	0	0	0
	48	0	0	0	0	0
	72	0	0	0	0	0

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: other: Directive 67/548/EEC or UN/EU GHS

Conclusions:

Cerium dioxide is not considered to be a skin irritant.

Executive summary:

In a primary dermal irritation study (Institut Français de Toxicologie report No. 302314), 3 male New Zealand White rabbits were dermally exposed to 0.5 g of Cerium dioxide moistened with 0.1 mL water applied on a ~6 cm² skin area maintained under semi-occlusive dressing for 4 hours. Animals then were observed for up to 72 hours. Irritation was scored 1, 24, 48 and 72 h after removal of the dressing by calculating dermal irritation scores, based on the grading of cutaneous erythema and edema.

 

No signs of cutaneous erythema or edema were observed. The dermal irritation scores were equal to 0.

 

The test substance was therefore considered as non-irritant to the skin. No classification for skin irritation is warranted based on the absence of cutaneous reactions following a 4 -hour exposure, according to the criteria of Annex VI Directive 67/548/EEC or UN/EU GHS.

 

This study is classified as acceptable. It satisfies the OECD 404 guideline requirements for acute dermal irritation or corrosion.