Cyanamide

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1982

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

The observation time points were not in accordance with the requirements of the OECD guideline 404.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1982

Report date:

1982

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

yes

Remarks:

skin reactions were scored at 4 and 52 hours after end of exposure instead of 24, 48 and 72 hours. Skin irritation study should not performed with abraded skin.

GLP compliance:

no

Remarks:

the study follows the recommendations of OECD guideline 404 broadly.

Test material

Test material information

Constituent 1

Reference substance name:

Cyanamide

EC Number:

206-992-3

EC Name:

Cyanamide

Cas Number:

420-04-2

Molecular formula:

CH2N2

IUPAC Name:

cyanamide

Test material form:

solid: crystalline

Details on test material:

- Name of test material (as cited in study report): SKW Cyanamid F1000
- Appearance: white crystalline material

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

No more details were indicated

Test system

Type of coverage:

semiocclusive

Preparation of test site:

abraded

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

0.5 mL of the undiluted test substance.

Duration of treatment / exposure:

4 hours

Observation period:

Approximately 4 hours after bandage removal and 52 hours after dosing.

Number of animals:

6 animals

Details on study design:

Twenty four hours prior to the test substance application the hair is removed from the back of the animals with electrical clippers in such a way as to avoid abrasions. An amount of 0.5 g of the test substance is brought on the intact or abraded skin under a surgical patch measuring 1 inch x 1 inch. The patches are fixed to the application site by means of adhesive tape and the entire trunk of the rabbits is wrapped with an impervious material to maintain the rest patches in position and to retard evaporation of volatile substances. Each rabbit is treated on the intact and abraded skin. The abrasions are minor incisions through the stratum corneum, but not sufficiently deep to disturb the derma or to produce bleeding. Effects of dermal irritation were recorded, at approximately 4 hours after bandage removal and 52 hours after dosing. The skin reactions are evaluated by the method of Draize.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal #1

Remarks:

(1016)

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: The score is the mean value of results at 4 and 52 h (results obtained from a treated animal with intact and not abraded skin).

Results 2

Irritation parameter:

erythema score

Basis:

animal #2

Remarks:

(1017)

Time point:

24/48/72 h

Score:

2.5

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: The score is the mean value of results at 4 and 52 h (results obtained from a treated animal with intact and not abraded skin).

Results 3

Irritation parameter:

erythema score

Basis:

animal #3

Remarks:

(1018)

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: The score is the mean value of results at 4 and 52 h (results obtained from a treated animal with intact and not abraded skin).

Results 4

Irritation parameter:

erythema score

Basis:

animal #4

Remarks:

(1019)

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: The score is the mean value of results at 4 and 52 h (results obtained from a treated animal with intact and not abraded skin).

Results 5

Irritation parameter:

erythema score

Basis:

animal #5

Remarks:

( 1020)

Time point:

24/48/72 h

Score:

3.5

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: The score is the mean value of results at 4 and 52 h (results obtained from a treated animal with intact and not abraded skin).

Results 6

Irritation parameter:

erythema score

Basis:

animal #6

Remarks:

(1021)

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: The score is the mean value of results at 4 and 52 h (results obtained from a treated animal with intact and not abraded skin).

Results 7

Irritation parameter:

edema score

Basis:

animal #1

Remarks:

(1016)

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: The score is the mean value of results at 4 and 52 h (results obtained from a treated animal with intact and not abraded skin).

Results 8

Irritation parameter:

edema score

Basis:

animal #2

Remarks:

(1017)

Time point:

24/48/72 h

Score:

2.5

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: The score is the mean value of results at 4 and 52 h (results obtained from a treated animal with intact and not abraded skin).

Results 9

Irritation parameter:

edema score

Basis:

animal #3

Remarks:

(1018)

Time point:

24/48/72 h

Score:

2.5

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: The score is the mean value of results at 4 and 52 h (results obtained from a treated animal with intact and not abraded skin).

Results 10

Irritation parameter:

edema score

Basis:

animal #4

Remarks:

(1019)

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: The score is the mean value of results at 4 and 52 h (results obtained from a treated animal with intact and not abraded skin).

Results 11

Irritation parameter:

edema score

Basis:

animal #5

Remarks:

(1020)

Time point:

24/48/72 h

Score:

2.5

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: The score is the mean value of results at 4 and 52 h (results obtained from a treated animal with intact and not abraded skin).

Results 12

Irritation parameter:

edema score

Basis:

animal #6

Remarks:

(1021)

Time point:

24/48/72 h

Score:

1.5

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: The score is the mean value of results at 4 and 52 h (results obtained from a treated animal with intact and not abraded skin).

Results 13

Irritation parameter:

erythema score

Basis:

mean

Time point:

24/48/72 h

Score:

2.8

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other:

Remarks:

The score is the mean value of results at 4 and 52 h (results obtained from a treated animal with intact and not abraded skin).

Results 14

Irritation parameter:

edema score

Basis:

mean

Time point:

24/48/72 h

Score:

3.3

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other:

Remarks:

The score is the mean value of results at 4 and 52 h (results obtained from a treated animal with intact and not abraded skin).

Irritant / corrosive response data:

The dermal effects observed , were as follows:
- after 4 hours: very slight to moderate erythema, focal haemorrhages and slight or moderate edema;
- after 52 hours: well-defined to moderate erythema, slight ischemia, very slight incrustation and very slight edema. The treated skin areas had a purple colour suggesting the presence of haemorrhages.
After one week the greater part of the treated skin areas showed slight to distinct necrosis.

Other effects:

No other effects

Any other information on results incl. tables

Table 1: Individual and average skin irritation scores of SKW Cyanamid F1000

 

rabbit number	intact skin		rabit number	abraded skin
	4 hours	52 hours		4 hours	52 hours
	A B	A B		A B	AB
1016	4-3	4-1	1016	2-3	4-1
1017	2-3	3-2	1017	2-3	3-1
1018	4-3	4-2	1018	2-3	4-1
1019	4-3	4-1	1019	2-3	4-1
1020	3-3	4-2	1020	4-3	3-1
1021	1-2	3-1	1021	2-3	2-1
average	5.8	5.2	average	5.3	4.3

A = erythma

B = edema

Applicant's summary and conclusion

Interpretation of results:

Category 1C (corrosive) based on GHS criteria

Conclusions:

From the present results it is concluded that SKW Cyanamid F1000 is a severe primary skin irritant and that it is corrosive to the skin of albino rabbits when brought into contact with the skin for four hours as necrotic damage to the skin was still observed 1 week after treatment.

Executive summary:

0.5 g of the test substance was applied to the intact or abraded skin of six New Zealand White rabbits. The application sites were covered with gauze bandaging secured with several wrappings of adhesive tape and provided semi-occlusive dressing. Approximately 4 hours after dosing the bandages and the test substance were removed. Dermal readings were taken at approximately 4 hours after bandage removal and 52 hours after dosing.

The observations showed that after 4 hours: very slight to moderate erythema, focal haemorrhages and slight or moderate edema. After 52 hours: well-defined to moderate erythema, slight ischemia, very slight incrustation and very slight edema were observed. The treated skin areas had a purple colour suggesting the presence of haemorrhages. After one week the greater part of the treated skin areas showed slight to distinct necrosis, therefore it can be concluded according to the CLP/GHS regulations that SKW Cyanamid F1000 is a severe primary skin irritant and that it is corrosive to the skin of albino rabbits when brought into contact with the skin for four hours.