Alkenes, C15-18 α-, sulfurized

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

3 February 1988 to 11 March 1988

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study conducted in accordance with generally accepted scientific principles, possibly with incomplete reporting or methodological deficiencies, which do not affect the quality of the relevant results.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1988

Report date:

1988

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Deviations:

yes

Remarks:

10 animals were treated with the test material

GLP compliance:

no

Type of study:

Buehler test

Justification for non-LLNA method:

A valid Buehler test already existed on the test material. In order to promote the refinement, reduction and replacement of animals it was considered unethical to run the same substance to the LLNA method.

Test material

Test material information

Constituent 1

Reference substance name:

Alkenes, C15-18 α-, sulfurized

EC Number:

267-023-8

EC Name:

Alkenes, C15-18 α-, sulfurized

Cas Number:

67762-55-4

Molecular formula:

Not applicable, complex UVCB

IUPAC Name:

Alkenes, C15-18 α-, sulfurized

Test material form:

other: liquid (unspecified)

Details on test material:

- Appearance: yellow liquid
- Recommended storage conditions: room temperature (approximately 22 °C)

In vivo test system

Test animals

Species:

guinea pig

Strain:

Hartley

Sex:

male

Details on test animals and environmental conditions:

TEST ANIMALS
- Age at study initiation: Adult.
- Weight at study initiation: Approximately 300 to 350 g.
- Housing: The guinea pigs were housed individually in stainless steel cages measuring 23.9 x 17.8 x 39.8 cm. Alfalfa pellets were placed in the pan below the stainless steel mesh floor of each animal cage to absorb liquids.
- Diet (e.g. ad libitum): Guinea Pig Chow was available ad libitum.
- Water (e.g. ad libitum): Water supplied from a reverse-osmosis purifier by an automatic watering system was available ad libitum.
- Acclimation period: 4 weeks.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): Maintained at approximately 22 °C.
- Humidity (%): Maintained at approximately 40 % relative humidity.
- Photoperiod (hrs dark / hrs light): Fluorescent lighting was provided for 12 hours followed by 12 hours of darkness.

IN-LIFE DATES: From: 6 January 1988 To: 11 March 1985

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

other: topical

Vehicle:

other: SX-10 Base Oil was used for the induction phase. Light mineral oil was used for the challenge phase.

Induction 2

Concentration / amount:

The test material was applied as a 25% (v/v) concentration in SX-10 Base Oil during the induction phase.
A 0.1 % concentration (v/v) in light mineral oil was used during the challenge phase.

Challenge

Challenge 1

Route:

other: topical

Vehicle:

other: SX-10 Base Oil was used for the induction phase. Light mineral oil was used for the challenge phase.

Challenge 2

Concentration / amount:

The test material was applied as a 25% (v/v) concentration in SX-10 Base Oil during the induction phase.
A 0.1 % concentration (v/v) in light mineral oil was used during the challenge phase.

No. of animals per dose:

10 animals were dosed with the test material.

Details on study design:

PRELIMINARY TESTING
The use of the 0.1 % concentration was based on the results of preliminary testing.

SKIN PREPARATION
Approximately 24 hours prior to test material application, the backs of the treated guinea pigs were clipped free of hair. The upper left quadrant was clipped for the induction applications and the lower left or right quadrant was clipped for the challenge applications. Hair from the lower left or right quadrant was clipped from the backs of the control guinea pigs 24 hours prior to the challenge applications.

INDUCTION
0.3 mL of the 25 % dosage formulation was applied to the upper left quadrant of ten guinea pigs, using a Hill Top Chamber once per week for a period of three weeks. An elastic adhesive bandage was wrapped around the midsection of the guinea pigs to keep the Hill Top Chamber in place. All wrapping materials were removed 6 hours after each application.

CHALLENGE
Two weeks following the application of the last induction phase dose, 0.3 mL of 0.1 % test material concentration was applied to the lower left quadrant of the backs of the ten treated and ten control guinea pigs. The test material was applied as described above. All wrapping materials were removed 6 hours after each application. A second challenge dose was applied to the lower right quadrant of all guinea pigs in an identical manner one week later.

SKIN EXAMINATION
Approximately 24 and 48 hours after removal of each challenge patch, the test sites were scored for erythema according to the method of Draize shown below. Guinea pigs were depilated with hair remover approximately 2 hours prior to each 24 hour scoring.

SCORING OF SKIN REACTIONS
0 No erythema
1 Very slight erythema (barely perceptible)
2 Well-defined erythema
3 Moderate to severe erythema
4 Severe erythema (beet redness) to slight eschar formation (injuries in depth)

Positive control substance(s):

no

Results and discussion

In vivo (non-LLNA)

Results

Results 1

Reading:

other: First challenge

Hours after challenge:

24

Group:

test chemical

Dose level:

0.1 %

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

1 animal had an erythema score of 1 which was below the positive score cut-off value of ≥2

Remarks on result:

other: see Remark

Remarks:

Reading: other: First challenge. . Hours after challenge: 24.0. Group: test group. Dose level: 0.1 %. No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: 1 animal had an erythema score of 1 which was below the positive score cut-off value of ≥2.

Results 2

Reading:

other: First challenge

Hours after challenge:

48

Group:

test chemical

Dose level:

0.1 %

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

1 animal had an erythema score of 1 which was below the positive score cut-off value of ≥2

Remarks on result:

other: see Remark

Remarks:

Reading: other: First challenge. . Hours after challenge: 48.0. Group: test group. Dose level: 0.1 %. No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: 1 animal had an erythema score of 1 which was below the positive score cut-off value of ≥2.

Results 3

Reading:

other: First challenge

Hours after challenge:

24

Group:

negative control

Dose level:

0.1 %

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

1 animal had an erythema score of 1 which was below the positive score cut-off value of ≥2

Remarks on result:

other: see Remark

Remarks:

Reading: other: First challenge. . Hours after challenge: 24.0. Group: negative control. Dose level: 0.1 %. No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: 1 animal had an erythema score of 1 which was below the positive score cut-off value of ≥2.

Results 4

Reading:

other: First challenge

Hours after challenge:

48

Group:

negative control

Dose level:

0.1 %

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

1 animal had an erythema score of 1 which was below the positive score cut-off value of ≥2

Remarks on result:

other: see Remark

Remarks:

Reading: other: First challenge. . Hours after challenge: 48.0. Group: negative control. Dose level: 0.1 %. No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: 1 animal had an erythema score of 1 which was below the positive score cut-off value of ≥2.

Results 5

Reading:

other: Second challenge

Hours after challenge:

24

Group:

test chemical

Dose level:

0.1 %

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

4 animals had an erythema score of 1 which was below the positive score cut-off value of ≥2

Remarks on result:

other: see Remark

Remarks:

Reading: other: Second challenge. . Hours after challenge: 24.0. Group: test group. Dose level: 0.1 %. No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: 4 animals had an erythema score of 1 which was below the positive score cut-off value of ≥2.

Results 6

Reading:

other: Second challenge

Hours after challenge:

48

Group:

test chemical

Dose level:

0.1 %

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

5 animals had an erythema score of 1 which was below the positive score cut-off value of ≥2

Remarks on result:

other: see Remark

Remarks:

Reading: other: Second challenge. . Hours after challenge: 48.0. Group: test group. Dose level: 0.1 %. No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: 5 animals had an erythema score of 1 which was below the positive score cut-off value of ≥2.

Results 7

Reading:

other: Second challenge

Hours after challenge:

24

Group:

negative control

Dose level:

0.1 %

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

3 animals had an erythema score of 1 which was below the positive score cut-off value of ≥2

Remarks on result:

other: see Remark

Remarks:

Reading: other: Second challenge. . Hours after challenge: 24.0. Group: negative control. Dose level: 0.1 %. No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: 3 animals had an erythema score of 1 which was below the positive score cut-off value of ≥2.

Results 8

Reading:

other: Second challenge

Hours after challenge:

48

Group:

negative control

Dose level:

0.1 %

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

3 animals had an erythema score of 1 which was below the positive score cut-off value of ≥2

Remarks on result:

other: see Remark

Remarks:

Reading: other: Second challenge. . Hours after challenge: 48.0. Group: negative control. Dose level: 0.1 %. No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: 3 animals had an erythema score of 1 which was below the positive score cut-off value of ≥2.

Results 9

Reading:

1st reading

Group:

positive control

Remarks on result:

not measured/tested

Any other information on results incl. tables

Summary of Preliminary Testing

Date of Testing	Test Material Concentration (%)	Vehicle	Erythema Score
13 January 1988	75 50 25	Mineral Oil Mineral Oil Mineral Oil	2 2 2
15 January 1988	10 5 1	Mineral Oil Mineral Oil Mineral Oil	2 2 2
20 January 1988	1	SX-10 Base Oil	2
26 January 1988	75 50 25	SX-10 Base Oil SX-10 Base Oil SX-10 Base Oil	2 2 1 - 2
22 February 1988	1 0.5 0.25	SX-10 Base Oil SX-10 Base Oil SX-10 Base Oil	2 1 - 2 2
24 February 1988	0.5 0.25	SX-10 Base Oil SX-10 Base Oil	2 2
29 February 1988	0.1 0.5 0.25 0.1	SX-10 Base Oil Mineral Oil Mineral Oil Mineral Oil	2 1 1 0 - 1

 

Results from the Definitive Study

Mortality

No deaths occurred during the study.

 

Skin Effects

Positive erythema reactions (i.e. a score ≥2) were not observed in any of the treated or control guinea pigs following either the 1st or the 2nd challenge.

 

Body Weights

Increases in mean body weights were observed in the treated and control guinea pigs during the study. Mean bodyweight gain over the duration of the study was 202.2 g in the control animals and 184.5 g in the treated animals

 

Evaluation

Results of the log-linear model are presented below. Based on this statistical analysis, the main effects of treatment, challenge, and time of scoring were not significant factors.

The following are the results of the log-linear analysis.

 

The main effect of treatment was not significant:

Chi-square = 0.38

Degrees of freedom (df) = 1

Probability (p) = ns

 

Challenge was not a significant factor:

Chi-square = 0.09

df = 1

p = ns

 

Time of scoring was not a significant factor:

Chi-square = 0.03

df = 1

p = ns

 

A minimum significance level of p≤0.05 was used in all comparisons.

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Under the conditions of this study the test material was determined not to be a sensitiser and therefore requires no classification in accordance with EU criteria.

Executive summary:

The potential of the test material to be a contact sensitiser was investigated in a study conducted in accordance with methodology broadly equivalent to the standardised guideline OECD 406.

The test material was applied at a concentration of 25 % (v/v) in SX-10 Base Oil in 0.3 mL doses to the shaved backs of ten guinea pigs once per week during an induction period of three weeks. Two and three weeks following the induction period, the treated guinea pigs, along with ten control guinea pigs, received a challenge dose of 0.3 mL of the test material at a 0.1 % concentration (v/v) in light mineral oil at different sites on the back. All guinea pigs were scored for erythema approximately 24 and 48 hours following the application of each challenge dose.

Positive erythema reactions (i.e. a score ≥2) were not observed in any of the treated or control guinea pigs following either challenge.

Under the conditions of this study the test material was determined not to be a sensitiser and therefore requires no classification in accordance with EU criteria.