Methyl hexanoate

Exposure related observations in humans: other data

Administrative data

Endpoint:

exposure-related observations in humans: other data

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

29 Jun - 03 Jul 1998

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Test procedure in accordance with generally accepted scientific standards and described in sufficient detail (analytical purity not specified).

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1998

Report date:

1998

Materials and methods

Type of study / information:

study with volunteers

Endpoint addressed:

skin irritation / corrosion

Test guideline

Qualifier:

according to guideline

Guideline:

other: The test was conducted according to COLIPA standard.

Deviations:

yes

Remarks:

lack of details on test substance

Principles of method if other than guideline:

Test substance is applied undiluted to the human skin of the back. Skin reactions are scored 6, 24, 48 and 72 hours after removal of the patch.

GLP compliance:

no

Remarks:

but GCP compliant

Test material

Test material information

Constituent 1

Reference substance name:

Methyl hexanoate

EC Number:

203-425-1

EC Name:

Methyl hexanoate

Cas Number:

106-70-7

Molecular formula:

C7H14O2

IUPAC Name:

methyl hexanoate

Details on test material:

- Name of test material (as cited in study report): methyl caproate
- Analytical purity: no data

Method

Ethical approval:

confirmed and informed consent free of coercion received

Details on study design:

Subjects:
- Number of subjects exposed: 20
- Sex: male and female
- Age: without restriction, not documented

Type of exposure:
Dermal, under occlusive conditions.

Study conduct:
An amount of 70 µL of the test substance was applied on the back of volunteers for 24 h with occlusive patches (Fin Chamber on Scanpor, 12 mm). The skin was subsequently examinated at 6, 24, 48 and 72 h and effects were graded according to the scale of Frosch and Kligman, J Am Acad Dermatol 1: 35-41, 1979.

Reference substances:
The following substances were used as references: Cosmet. alcohol, paraffin oil, Texapon N28 (1%), SDS, water, and phys. sodium chloride (NaCl).

Exposure assessment:

measured

Results and discussion

Results:

The aim of this test method is the induction of skin reactions with concentrations of test substances higher than the commercial use (e.g. undiluted) for comparison of the reactions with positive (e.g. sodium dodecyl sulfate (SDS)) and negative controls (e.g. water).
moderate erythema was seen in 8/20 volunteers, two individuals also had moderate desquamation (mean score for erythema: 1.79; mean score for erythema, edema, desquamation and fissure: 3.37). The moderate reactions occuring under 24 h occlusive test conditions indicate that the undiluted test substance methyl caproate is satisfactorily compatible to human skin. The positive test result obtained for SDS confirmed the validity of the test.

Any other information on results incl. tables

Number of reactions for the parameters erythema, edema and desquamation added up from all time points (6, 24, 48, and 72 h) and differentiated according to the strength.

Scoring		Erythema					Edema					Desquamation
Substance	Without reaction	1	2	3	4	0	1	2	3	4	0	1	2	3	4	0
Methyl caproate	5/20	18	8	0	0	50	0	0	0	0	76	26	2	0	0	48
SDS 0.5%	2/20	39	11	0	0	26	1	0	0	0	75	25	3	0	0	48
Water	19/20	1	0	0	0	75	0	0	0	0	76	0	0	0	0	76
Cosmet. alcohol	18/20	2	0	0	0	74	0	0	0	0	76	5	0	0	0	71
Paraffin oil	20/20	0	0	0	0	76	0	0	0	0	76	0	0	0	0	76
Texapon N28 1%	7/20	28	0	0	0	48	0	0	0	0	76	22	0	0	0	54
Phys. NaCl	19/20	2	0	0	0	74	0	0	0	0	76	1	0	0	0	7

Scoring according to Frosch P.J. & Kligman A.M., The soap chamber test; a new method for assessing the irritancy of soaps, J Am Acad Dermatol 1: 35-41, 1979

0 = no reactions

1 = slight reactions

2 = moderate reactions

3 = strong uniform reactions

4 = really strong reactions

Applicant's summary and conclusion

Conclusions:

The study guideline from COLIPA is in accordance with generally accepted scientific standards, which makes the study report acceptable for assessment. According to C&L guide Art. 3.2.6.1. (EC, 1993a) R38 is to be applied to “substances and preparations which cause significant inflammation of the skin, based on practical observation in humans on immediate, prolonged or repeated contact”. The lack of such effects leads to the classification of the test substance methyl caproate as not irritating to human skin.