Octanal

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

Not documented

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

The published study information describes a valid procedure for assessment of sensitising potential, cross referenced to various similar materials (common group of aldehydes). Some of the materials tested in the study are used as positive control materals for guideline compliant sensitisation assays, and the positive results obtained in this publication validate the published method to some degree.

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

publication

Title:

Skin Reaction Induced by Aldehydes for Food Flavouring Agents

Author:

Watanabe, K. Matsuda, M. Furuhashi, S. Kimura, T. Matsunga, T. Yamamoto, I.

Year:

2001

Bibliographic source:

Journal of Health Science, 47 (3) 327-329 (2001)

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

n-octanal was dissolved in saline containing 1% Tween 80. For sensitization, the animals were injected with 0.1 ml of n-octanal solution (1.0%) intracutaneously on both sides of the abdomen for 7 days. Three weeks later, elicitation experiments were carried out with an injection of 0.1 ml of 0.25, 0.5% and 1.0% n-octanal solution or saline containing I% Tween 80 as the control. The abdomen of each animal was depilated with a hair remover prior to the elicitation of a skin reaction. Skin reactions were graded based on reaction diameter 24 hr after the injection of n-octanal or the control as follows:
0 to 1.0 mm -,
1.0 to 2.0 mm ±,
2.0 to 4.0 mm +,
4.0 to 6.0 mm ++,
6.0 to 8.0 mm +++.

GLP compliance:

not specified

Type of study:

other: Guinea pig sensitisation

Justification for non-LLNA method:

The test was performed in 2001 when the OECD Guideline 406 adopted in 1992 was the current version. According to this guideline "the Guinea Pig Maximisation Test (GPMT) [...] and the non-adjuvant Buehler Test are given preference over other methods".“

Test material

Test material information

Constituent 1

Reference substance name:

n-octanal

IUPAC Name:

n-octanal

Constituent 2

Reference substance name:

Octanal

EC Number:

204-683-8

EC Name:

Octanal

Cas Number:

124-13-0

Molecular formula:

C8H16O

IUPAC Name:

octanal

Test material form:

not specified

Details on test material:

No information provided

In vivo test system

Test animals

Species:

guinea pig

Strain:

Hartley

Sex:

male

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Sankyo Laboratory ( Toyama, Japan)
- Age at study initiation: 8 weeks old
- Weight at study initiation: 300-400g
- Housing: Not documented
- Diet (e.g. ad libitum): Ad libitum
- Water (e.g. ad libitum): Ad libitum
- Acclimation period: Not documented

ENVIRONMENTAL CONDITIONS
No details provided

IN-LIFE DATES: From: To: Not documented - paper published in February 2001

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

intradermal

Vehicle:

other: 1% Tween 80

Induction 2

Concentration / amount:

induction 1%
challenge 0.25%, 0.5% and 1.0%

Challenge

Challenge 1

Route:

intradermal

Vehicle:

other: 1% Tween 80

Challenge 2

Concentration / amount:

induction 1%
challenge 0.25%, 0.5% and 1.0%

No. of animals per dose:

3-4 animals were used per group and 3 animals were used for the control group.

Details on study design:

No further information provided

Challenge controls:

Control animals received 0.1 ml of saline-I % Tween 80 solution intracutaneously.

Positive control substance(s):

not required

Results and discussion

Positive control results:

No information

In vivo (non-LLNA)

Results

Results 1

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

0.25%

No. with + reactions:

3

Total no. in group:

3

Clinical observations:

reactions fron + to +++ observed

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 0.25%. No with. + reactions: 3.0. Total no. in groups: 3.0. Clinical observations: reactions fron + to +++ observed.

Results 2

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

0.5%

No. with + reactions:

3

Total no. in group:

3

Clinical observations:

reactions from ++ to +++ observed

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 0.5%. No with. + reactions: 3.0. Total no. in groups: 3.0. Clinical observations: reactions from ++ to +++ observed.

Results 3

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

1.0%

No. with + reactions:

3

Total no. in group:

3

Clinical observations:

All +++ reactions

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 1.0%. No with. + reactions: 3.0. Total no. in groups: 3.0. Clinical observations: All +++ reactions.

Results 4

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

0%

No. with + reactions:

0

Total no. in group:

3

Clinical observations:

reactions from - to ± observed

Results 5

Group:

positive control

Remarks on result:

not measured/tested

Any other information on results incl. tables

Skin Reaction Induced by n-Octanal

Concentration of n-Octanal used for Skin Reaction
Animal number	0 (Saline-Tween 80)	0.25%	0.5%	1.0%
1	-	+	++	+++
2	-	++	++	+++
3	±	+++	+++	+++

 

-            0 to 1.0mm

±      1.0 to 2.0mm

+      2.0 to 4.0mm

++    4.0 to 6.0mm

+++   6.0 to 8.0mm

Applicant's summary and conclusion

Interpretation of results:

sensitising

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

n-octanal elicited an allergic response in three guinea pigs tested in an intracutaneous test and as such, was considered to be a potential skin sensitiser

Executive summary:

In this study, Guinea pigs were sensitised intracutaneously on both sides of the abdomen for 7 days at a concentration of 0.1 ml of 1% n-octanal/day. Three weeks later n-octanal was injected intracutaneously to 12 male guinea pigs per test and control group at a concentration of 0.1%, 0.5% and 1.0% of n-octanal. Control animals received 0.1 ml of saline-I % Tween 80 solution intracutaneously instead of the n-octanal solution. At the test concentrations used in this study, the test substance did elicit allergenic responses and as such, is considered to be a potential skin sensitiser.