ASTM International

Standard Guide for Sensory Evaluation of Axillary Deodorancy
 N E1207

Annotation

This guide provides procedures which may be used in the design and analysis of studies to quantitatively assess the intensity of human axillary odor for the purpose of substantiating deodorant efficacy of personal care products.

This guide includes protocols for the selection and training of assessors, selection of subjects, experimental design, and statistical analyses. This practice is limited to assessment of axillary odor by trained assessors. Selfevaluation protocols are valid for selected sensory tasks but may be less sensitive.

With respect to the source of axillary odor, three groups of secretory glands are present in the axillae which participate to a greater or lesser extent in its production—eccrine, apocrine, and sebaceous. Axillary odor has been primarily ascribed to the apocrine gland secretion (1).2 Body odor intensity has been correlated with the volume of the secretory portion of the apocrine gland (2) and the density of the glands.

Apocrine glands are found primarily in the axillary vault in conjunction with axillary hairs (3). Pure apocrine sweat is sterile and odorless and axillary odor results from degradation of apocrine sweat by resident skin bacteria (4). High bacterial populations are found in moist regions of the body, especially in the axillae, providing the appropriate environment for growth (5).

Eccrine glands keep the axillae moist through thermally and emotionally induced secretions (6).

The sebaceous glands excrete higher molecular weight lipid materials which absorb and retain the volatile materials resulting from bacterial action (7). The aerobic diphtheroids are able to produce the typical acrid axillary odor and the micrococcaceae produce an isovaleric acid-like odor when incubated with apocrine sweat (8). Therefore, the most undesirable component of axillary odor is caused by degradation of apocrine sweat by particular bacteria normally found in the axillary vault.