6-chloro-2-(6-chloro-4-methyl-3-oxobenzo[b]thien-2(3H)-ylidene)-4-methylbenzo[b]thiophene-3(2H)-one

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:

other: Test performed before OECD and GLP guideline implementation. Important aspects (dosing, observation times, grading criteria) comparable with current OECD guidelines.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1977

Report date:

1977

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: Federal Register 38, No. 187, 27. 9. 1973, p 27019, § 1500.41

Deviations:

no

GLP compliance:

no

Remarks:

previous to GLP implementation

Test material

Test material information

Constituent 1

Reference substance name:

6-chloro-2-(6-chloro-4-methyl-3-oxobenzo[b]thien-2(3H)-ylidene)-4-methylbenzo[b]thiophene-3(2H)-one

EC Number:

219-163-6

EC Name:

6-chloro-2-(6-chloro-4-methyl-3-oxobenzo[b]thien-2(3H)-ylidene)-4-methylbenzo[b]thiophene-3(2H)-one

Cas Number:

2379-74-0

Molecular formula:

C18H10Cl2O2S2

IUPAC Name:

6-chloro-2-[(2E)-6-chloro-4-methyl-3-oxo-2,3-dihydro-1-benzothiophen-2-ylidene]-4-methyl-2,3-dihydro-1-benzothiophen-3-one

Test material form:

solid: nanoform

Test animals

Species:

rabbit

Strain:

Himalayan

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Strain: SPF-Albino-Himalayan
- Source: Hoechst AG, breeding colony
- Weight at study initiation: 1,5 - 2,0 kg
- Housing: single caged
- Diet: standard diet ERKA 8300 ad libitum
- Water: tap water ad libitum

Test system

Type of coverage:

occlusive

Preparation of test site:

other: shaved intact or shaved abraded with a scarifying instrument

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

0.5 g

Duration of treatment / exposure:

24 h

Observation period:

examinations: 24, 48 and 72 h after application, i.e. 0, 24, 48 h after the end of treatment/exposure

Number of animals:

6

Details on study design:

0.5 g of the undiluted test substance is spread on a gauze patch, measuring 2,5 x 2,5 cm which is applied on the abraded and intact skin of 6 albino rabbits, clipped free of hair under occlusive conditions. After 24 hours of exposure, the patches are removed. Reactions are recorded 0, 24 and 48 h after the end of exposure.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

edema score

Basis:

animal: # 49-52, 94, 95 each

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

fully reversible

Remarks on result:

no indication of irritation

Results 2

Irritation parameter:

erythema score

Basis:

animal: # 49-52, 94, 95 each

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

fully reversible

Remarks on result:

no indication of irritation

Irritant / corrosive response data:

No skin reactions were observed in any animal at any time point.
Due to pigment overla y, erythema score could not be evaluated 24 h after application (time point 0).

Other effects:

no other effects reported

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Remarks:

regulation (EC) 1272/2008

Conclusions:

According to the classification criteria of Regulation (EC) No 1272/2008 the test material is not irritating to skin under these test conditions.

This conclusion is legitimate even though the applied testing regime differs from today's standard methods. Since the test conditions were more stringent than required by OECD TG 404 (i.e. 24 h treatment, occlusive coverage, and scarified skin instead of 4 h treatment, semi-occlusive coverage, and intact skin) the test results are considered adequate to fulfill the endpoint requirements.

Executive summary:

Test material was subject to an acute dermal irritation/corrosion test in 6 Himalaya rabbits according to FDA guideline. Both intact and scarified skin sites of six rabbits were exposed to 500 mg test substance for 24 h under occlusive conditions and the skin responses were examined 0, 24, and 48 h after the end of exposure. Due to discoloration of the skin erythema score could not be evaluated 24 h after application. No skin reactions were observed at any other observation time point. Therefore, the test item has not to be classified for skin irritation according to Regulation (EC) No 1272/2008.