[No public or meaningful name is available]

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from August 2001 to 12 December 2001

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2001

Report date:

2001

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

yes

Remarks:

temperature and relative humidity were sometimes out of the target, and the initial body weight of one animal was slightly lower than 2.2kg (minor deviation)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

753480-32-9

Cas Number:

753480-32-9

IUPAC Name:

753480-32-9

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: CEGAV, Saint Mars d'Egrenne, France.
- Age at study initiation: data not available.
- Weight at study initiation: 2.4 ± 0.2 kg (one animal was slightly lower: 2.194kg).
- Housing: individually in polystyrene cages (48.2 cm x 58 cm x 36.5 cm).
- Diet: 110 pellet diet (UAR, Villemoisson, Epinay-Sur-Orge, France), ad libitum.
- Water: filtered drinking water, ad libitum.
- Acclimation period: at least 5 days.

ENVIRONMENTAL CONDITIONS
- Temperature: 18 ± 3°C.
- Humidity: 30 to 70%.
- Air changes: approximately 12 cycles/hour.
- Photoperiod: 12 h light/12 h dark.

IN-LIFE DATES: from 28 August 2001 (first treatment) to 10 September 2001 (end of the observation period)

Test system

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

TEST MATERIAL
- Amount applied: 0.5 ml
- Concentration: undiluted
- Remark: the test substance was applied on a moistened gauze pad, in order to ensure a good contact with the skin.

Duration of treatment / exposure:

4 hours

Observation period:

7 days

Number of animals:

3

Details on study design:

TEST SITE
- Area of exposure: data not available
- % coverage: data not available
- Type of wrap if used: gauze pad held in contact with the skin by means of an adhesive hypoallergenic aerated semi-occlusive dressing and a restraining bandage.

REMOVAL OF TEST SUBSTANCE
- Washing: yes (wiped off by means of a moistened gauze pad).
- Time after start of exposure: 4 hours.

OBSERVATION TIME POINTS
Reading of the skin erythema and oedema scores were performed after the removal of the dressing at 1h, 24, 48 and 72h, and then days 4, 5, 6 and 7 of the study.

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 (beet redness) to slight eschar formation (injuries in depth) -> 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 millimetre) -> 3
. severe oedema (raised more than 1 millimetre and extending beyond area of exposure) -> 4

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Remarks:

3 rabbits

Time point:

24/48/72 h

Score:

1.2

Max. score:

4

Reversibility:

fully reversible within: 7 days

Remarks on result:

other: No erythema was observed at 24/48/72 hours but as a brown coloration of the skin was noted due to the test substance which could have masked a possible erythema (grade 1 or 2), a possible maximal mean score was calculated for erythema (mean of 3 rabbits).

Results 2

Irritation parameter:

edema score

Basis:

mean

Remarks:

3 rabbits

Time point:

24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

no indication of irritation

Results 3

Irritation parameter:

erythema score

Basis:

animal: 883

Time point:

24 h

Score:

2

Remarks on result:

other: brown coloration of the skin which could have masked a possible well-defined erythema

Results 4

Irritation parameter:

erythema score

Basis:

animal: 883

Time point:

48 h

Score:

2

Remarks on result:

other: brown coloration of the skin which could have masked a possible well-defined erythema

Results 5

Irritation parameter:

erythema score

Basis:

animal: 883

Time point:

72 h

Score:

1

Reversibility:

fully reversible within: 6 days

Remarks on result:

other: brown coloration of the skin which could have masked a possible very slight erythema

Results 6

Irritation parameter:

erythema score

Basis:

animal: 835

Time point:

24 h

Score:

0

Results 7

Irritation parameter:

erythema score

Basis:

animal: 835

Time point:

48 h

Score:

0

Results 8

Irritation parameter:

erythema score

Basis:

animal: 835

Time point:

72 h

Score:

0

Reversibility:

fully reversible within: 1 day

Results 9

Irritation parameter:

erythema score

Basis:

animal: 836

Time point:

24 h

Score:

2

Remarks on result:

other: brown coloration of the skin which could have masked a possible well-defined erythema

Results 10

Irritation parameter:

erythema score

Basis:

animal: 836

Time point:

48 h

Score:

2

Remarks on result:

other: brown coloration of the skin which could have masked a possible well-defined erythema

Results 11

Irritation parameter:

erythema score

Basis:

animal: 836

Time point:

72 h

Score:

2

Reversibility:

fully reversible within: 7 days

Remarks on result:

other: brown coloration of the skin which could have masked a possible well-defined erythema

Results 12

Irritation parameter:

edema score

Basis:

animal: 883

Time point:

24 h

Score:

0

Results 13

Irritation parameter:

edema score

Basis:

animal: 883

Time point:

48 h

Score:

0

Results 14

Irritation parameter:

edema score

Basis:

animal: 883

Time point:

72 h

Score:

0

Results 15

Irritation parameter:

edema score

Basis:

animal: 835

Time point:

24 h

Score:

0

Results 16

Irritation parameter:

edema score

Basis:

animal: 835

Time point:

48 h

Score:

0

Results 17

Irritation parameter:

edema score

Basis:

animal: 835

Time point:

72 h

Score:

0

Results 18

Irritation parameter:

edema score

Basis:

animal: 836

Time point:

24 h

Score:

0

Results 19

Irritation parameter:

edema score

Basis:

animal: 836

Time point:

48 h

Score:

0

Results 20

Irritation parameter:

edema score

Basis:

animal: 836

Time point:

72 h

Score:

0

Irritant / corrosive response data:

A brown coloration of the skin, due to the test substance, was observed in all animals; it could have masked a possible very slight or well-defined erythema (grade 1 or 2) in all three animals on day 1 and up to day 5 (one animal) or 6 (one animal).
No erythema and no oedema were observed.

However, taking into account the coloration of the test substance, the maximal mean scores over 24, 48 and 72 hours for each animal could possibly be 1.7, 0.0 and 2.0 for erythema.
The mean scores over 24, 48 and 72 hours for each animal were 0.0, 0.0 and 0.0 for oedema.

Other effects:

A brown coloration of the skin, due to the test substance, was observed in all animals.

Any other information on results incl. tables

Summary table of individual irritation scores:

Rabbit number	Dermal irritation	Scores							Mean irritation score
		1h	24h	48h	72h	D5	D6	D7
883	Erythema Oedema Other	C 0 *	C 0 *	C 0 *	C 0 *	C 0 *	0 0 C	- - -	n.d. 0.0
835	Erythema Oedema Other	C 0 *	0 0 C	0 0 C	0 0 C	- - -	- - -	- - -	0.0 0.0
836	Erythema Oedema Other	C 0 *	C 0 *	C 0 *	C 0 *	C 0 *	C 0 *	0 0 C	n.d. 0.0

n.d. = not determined

* = None

C = brown coloration of the skin

- = examination not performed

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Cerium and iron oxide isostearate is not considered to be a skin irritant in the rabbit.

Executive summary:

In a primary dermal irritation study performed according to OECD 404 and GLP (CIT report No. 22320 TAL), scored as validity 1 according to Klimisch criteria, 3 male New Zealand White rabbits were dermally exposed to 0.5 g of cerium and iron oxide isostearate applied on the skin of flanks and maintained under semi-occlusive dressing for 4 hours. Animals then were observed for up to 7 days. Irritation was scored 1, 24, 48, 72 h and on days 5, 6 and 7 after removal of the dressing by calculating dermal irritation scores, based on the grading of cutaneous erythema and edema.

 

A brown coloration of the skin, due to the test substance, was observed in all animals and could have masked a possible very slight or well-defined erythema in all three animals on day 1 and up to day 5 (one animal) or 6 (one animal).No erythema and no oedema were observed.

However, taking into account the coloration of the test substance, the maximal mean scores over 24, 48 and 72 hours for each animal could possibly be 1.7, 0.0 and 2.0 for erythema.

The mean scores over 24, 48 and 72 hours for each animal were 0.0, 0.0 and 0.0 for oedema.

 

 

The test substance was considered as non-irritant to the skin. No classification for skin irritation is warranted based on the observed 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.