Naphthalenesulfonic acids, branched and linear Bu derivs., sodium salts

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

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

Adequacy of study:

key study

Study period:

November 19, 1996 until December 20, 1996.

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

Reliability of original study is 1

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1997

Report date:

1997

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

GLP compliance:

yes

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

Results of guinea pig maximisation test were available.

Test material

Test material information

Constituent 1

Reference substance name:

Sodium diisobutylnaphthalenesulphonate

EC Number:

248-326-4

EC Name:

Sodium diisobutylnaphthalenesulphonate

Cas Number:

27213-90-7

Molecular formula:

C18H24O3S.Na

IUPAC Name:

sodium 2,3-diisobutylnaphthalene-1-sulfonate

Test material form:

solid: particulate/powder

In vivo test system

Test animals

Species:

guinea pig

Strain:

other: Pirbright White

Sex:

female

Study design: in vivo (non-LLNA)

Induction

Route:

intradermal and epicutaneous

Vehicle:

water

Concentration / amount:

intradermal induction with 0.5 % test substance
percutaneous induction with a 50 % test substance preparation

Challenge

Route:

other: percutaneous induction.

Vehicle:

water

No. of animals per dose:

The study was performed on 20 guinea pigs in the test group and 10 animais in each of control groups 1 and 2.

Results and discussion

In vivo (non-LLNA)

Results

Results 1

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

test substance 25% in aqua bidest.

No. with + reactions:

5

Total no. in group:

19

Results 2

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

test substance 25% in aqua bidest.

No. with + reactions:

3

Total no. in group:

18

Any other information on results incl. tables

The number of animais with skin findings after the ist challenge and after the 2nd challenge is summarized in the following table:

	1st challenge		2st challenge
	test substance 25% in aqua bidest.		test substance 25% in aqua bidest.
	After 24 hours	After 48 hours	After 24 hours	After 48 hours
Control group 1	0/10	0/10	0/10	0/10
Control group 2**	no application of test substance		0/7	0/7
Test group**	5/19	3/18	0/17	0/17

x/y: number of positive reactions/number of animais tested (reading at 24 h and/or 48 h after the removal of the patch)

**: 3 test group animais and 3 animais of control group 2 died 18, 21, 22, 23 or 25 days after the beginning of the study. Macroscopic examination revealed that the cause of death was not substance related.

Applicant's summary and conclusion

Interpretation of results:

other: not classified as a skin sensitiser according to the CLP Regulation (EC) No.1272/2008

Conclusions:

not a skin sensitiser

Executive summary:

The substance was tested for its sensitizing effect an the skin of the guinea pig in the Maximization Test based on the method of Magnusson and Kligman. The intradermal induction with 0.5 % test substance preparations caused slight to well-defined signs of 5km irritation or necrotic skin changes in test group animais. After the percutaneous induction with a 50 % test substance preparation incrustation, partially open (caused by the intradermal induction; could be observed in addition to well-defined erythema and slight edemna or necrotic skin changes (caused by the * intradermal induction) and slight edema in test group animais. Two challenges were performed 14 and 21 days after the percutaneous induction.

After the first challenge with a 25 % test substance preparation very slight to well-defined 5km reactions could be observed in test group animais. The second challenge with a 25% test substance preparation did not cause any skin reaction.

Based on the results of this study it was concluded that the test item does not have a sensitizing effect on the skin of the guinea pig in the Maximization Test under the test conditions chosen.