Formaldehyde

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

Comparable to guideline study (BASF Test) with acceptable restrictions (exposure period 20 h; occlusive dressing; application of a patch soaked with ca. 1 mL formalin; partly limited documentation, no details about the test substance)

Data source

Reference

Reference 1

Reference Type:

study report

Title:

Unnamed

Year:

1974

Report Date:

1974

Reference 2

Reference Type:

study report

Title:

Unnamed

Year:

1973

Report Date:

1973

Materials and methods

Test guideline

Qualifier:

equivalent or similar to

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

yes

Remarks:

(20 h exposure, occlusive dressing)

GLP compliance:

no

Test material

Reference

Name:

Unnamed

Type:

Constituent

Test material form:

liquid

Specific details on test material used for the study:

40% formalin
no further details

Test animals

Species:

rabbit

Strain:

Vienna White

Details on test animals and environmental conditions:

1 male (initial body weight 3.03 kg) and 1 female rabbit (intial weight 3.36 kg)
no further details

Test system

Type of coverage:

occlusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

a patch (2.5 x 2.5 cm²) soaked with the liquid (formalin) corresponding to ca. 1 mL (0.5 mL recommended in OECD 404)

Duration of treatment / exposure:

20 h (washing of test site)

Observation period:

24, 48, 72 h and 6 and 8 days after application

Number of animals:

1 male and 1 female

Details on study design:

BASF scoring system converted into the presently used grading system (OECD 404)

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Time point:

24 h

Score:

2.5

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: full thickness necrosis

Results 2

Irritation parameter:

edema score

Basis:

mean

Time point:

24 h

Score:

3

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: full thickness necrosis

Irritant / corrosive response data:

full thickness necrosis was induced in both rabbits

Other effects:

slight reduction in body weight

Any other information on results incl. tables

Skin irritation in 2 rabbits

Scorring	Erythema	Edema	Remarks
	Exposure duration 20 h
24 h after initiation Rabbit 1 Rabbit 2	2 3	3 3	Superficial Ne & B Superficial Ne
48 h after initiation Rabbit 1 Rabbit 2	2 2	3 3	Ne Ne
72 h after initiation Rabbit 1 Rabbit 2	See remarks	See remarks	Ne Ne (parchmenty)
6 days Rabbit 1 Rabbit 2	See remarks	See remarks	Ne (leather like) Ne (black)
8 days Rabbit 1 Rabbit 2	See remarks	See remarks	Ne (black, hardened) Ne (black, hardened)

Ne: necrosis; B: bleeding

Applicant's summary and conclusion

Interpretation of results:

Category 1 (corrosive) based on GHS criteria

Conclusions:

A solution of 40% formalin induced full thickness necrosis in 2 rabbits after 20 h occlusive exposure.

Executive summary:

Comparable to guideline study (BASF Test) with acceptable restrictions (exposure period 20 h; occlusive dressing; application of a patch soaked with ca. 1 mL formalin; partly limited documentation, no details about the test substance).

Two White Vienna rabbits were exposed for 20 h under occlusive dressing to a patch (2.5 x 2.5 cm²) soaked with 40% formalin. Readings were performed 24, 48, 72 h and 6 and 8 days after application. Beside edema and erythema superficial necrosis was obvious 24 h after initiation of exposure. In both rabbits full thickness necrosis were found the following days.

Conclusion: A solution of 40% formalin induced full thickness necrosis in 2 rabbits after 20 h occlusive exposure.