Dodecane-1-thiol

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation

Remarks:

in vitro

Type of information:

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

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: This study is classified as reliable without restriction because it was conducted according to or similar to OECD guideline 406.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1995

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

Test material

Test material information

Constituent 1

Reference substance name:

1,1-dimethylheptanethiol (CAS # 25360-10-5)

IUPAC Name:

1,1-dimethylheptanethiol (CAS # 25360-10-5)

Details on test material:

t-nonyl mercaptan; ; EAP, batch 94-000606; purity 99%. (1,1-dimethylheptanethiol)

In vivo test system

Test animals

Species:

guinea pig

Strain:

Dunkin-Hartley

Sex:

male/female

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

intradermal

Vehicle:

other: paraffin oil

Induction 2

Concentration / amount:

.1 mL of 1% (w/w)
.5 mL of 75% (w/w)

Challenge

Challenge 1

Route:

other: cutaneous and semiocclusive

Vehicle:

other: paraffin oil

Challenge 2

Concentration / amount:

.1 mL of 1% (w/w)
.5 mL of 75% (w/w)

No. of animals per dose:

30

Details on study design:

1st application: Induction 1 % intracutaneous
2nd application: Induction undiluted occlusive epicutaneous
3rd application: Challenge 75 % occlusive epicutaneous

Positive control substance(s):

yes

Remarks:

paraffin oil

Results and discussion

Positive control results:

No effects of treatment were observed.

In vivo (non-LLNA)

Results

Results 1

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

75% concentration

No. with + reactions:

2

Total no. in group:

19

Clinical observations:

Moderate and confluent erythema

Remarks on result:

positive indication of skin sensitisation

Results 2

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

75% concentration

No. with + reactions:

1

Total no. in group:

19

Clinical observations:

Moderate and confluent erythema

Remarks on result:

positive indication of skin sensitisation

Results 3

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

75% concentration

No. with + reactions:

5

Total no. in group:

19

Clinical observations:

Discrete or patchy erythema

Remarks on result:

positive indication of skin sensitisation

Results 4

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

75% concentration

No. with + reactions:

0

Total no. in group:

19

Clinical observations:

Discrete or patchy erythema

Remarks on result:

no indication of skin sensitisation

Any other information on results incl. tables

Challenge Application:

Groups	Sex	Erythema Score	Scoring of the cutaneous parameters
			24 hours		48 hours
			LF	RF	LF	RF
Control 1	Male	0	5/5	5/5	4/4	4/4
Treated 2	Male	0	9/9	4/9	9/9	6/9
		1	-	4/9	-	2/9
		2	-	1/9	-	1/9
Control 1	Female	0	5/5	5/5	5/5	5/5
Treated 2	Female	0	10/10	8/10	10/10	9/10
		1	-	1/10	-	1/10
		2	-	1/10	-	-

Applicant's summary and conclusion

Interpretation of results:

Category 1B (indication of skin sensitising potential) based on GHS criteria

Conclusions:

According to the maximisation method established by Magnusson and Kligman, cutaneous reactions attributable to the sensitisation potential of the test substance, 1,1-dimethylheptanethiol at the concentration of 75% (w/w) were observed in 10% of the guinea-pigs. 1,1-dimethylheptanethiol was considered to be a weak sensitiser.

Executive summary:

In a dermal sensitisation study, using 1,1-dimethylheptanethiol, 15 male and 15 female Dunkin-Hartley guinea pigs were tested using the method of Magnusson and Kligman.

No treatment-related clinical signs or deaths were noted during the study. Well-defined erythema was observed in 2/19 animals 24 and 48 hours after removal of the dressing. No effects of the treatment were noted in the control group. In this study, 1,1-dimethylheptanethiol was a dermal sensitiser in 10% of the test animals.

 

This study received a Klimisch score of 1 and is classified as reliable without restriction because it dheres to guidelines and provides a robust data set.