Montfort A. Johnsen, Ph.D.
technical editor
Skin Moisturizers
vs. Emollients
BOV sprays are gaining momentum…
Our skin is the body’s largest organ and the only one exposed to all the vicissitudes of the environment.
It must tolerate solar radiation, changes in temperature and relative humidity, oxidation
(by oxygen, ozone and some chemicals), bacterial and fungal attacks, physical injuries (insect
bites, cuts and bruises), allergens and numerous air pollutants. Aside from obvious cosmetic aspects,
the primary function of the skin is to form a barrier that acts to conserve body moisture. To do this effectively,
the skin has evolved into a complex, multi-layered, flexible sheath, ranging from about 100 microns
to many times thicker in work-response (callused) areas.
There are nine species of our epidermis, such as the palms, lips and eyelids. The uppermost layer of our
skin is the Stratum Corneum (SC). It is only 5–10 microns thick, and until about 1950 was thought to be
dead tissue. Indeed, the very top portion continuously flakes off, almost unnoticeably, as the skin slowly rejuvenates
itself, typically about once per month. Currently, dermatologists recognize that the SC plays a critical
role in skin health. It is the primary target of innumerable personal care and pharmacological products,
generally called emollients, moisturizers or humectants. They are used to increase the moisture level of the
SC to about 20 to 30%, making it smoother, softer, more flexible and supple, as well as free of fissures, itching
and excessive flaking.
By doing so, these products counteract the problems caused by dry skin (xeroderma), where the moisture
content of the SC amounts to 10% or less. Dry skin is found in as many as 90% of adults. When the skin
is under stress, it becomes unsightly,
developing tiny protrusions (“sandpaper
syndrome”), and sometimes blotchy
red-brown pigmentations, especially on
the arms and lower legs. Itching can be
a significant problem. Dry skin disorders
increase with advancing age and can be
more troublesome in winter months where
the relative humidity is low. The U.S.
market for emollients was about $9 billion
in 2008 and is projected to be about $15
billion in 2018. It consists principally of
oil-in-water (o/w) creams, lotions and gels,
delivered using plastic dispensers. Aerosols
have limited penetration, but this is
increasing.
Skin problems
While dry skin problems are most prevalent,
there are a large number of other
ailments and diseases that challenge the
skin. Some are easily tolerated, while others,
such as melanoma, can be life threatening.
In many cases their origin is unknown,
and methods for their eradication
are also unknown. We must be satisfied by
mitigating them or tolerating them. Table
One lists a number of them, and their cur-
38 Spray October 2018
TABLE ONE
Dermal Malfunctions
Condition or Disorder
Lifetime Incident
Frequency
Actinic Keratosis Unknown
Actinic Lentigines (liver spots) Unknown
Athlete’s Foot (Tinea pedis) Very common
Atopic Dermititus (Xeroderma or dry skin) Common
Atypical Nevis Unknown
Cancers
Basal Cell Carcinoma >500,000 per year
Squamous Cell Carcinoma 280,000 per year
Malignant Melanoma 32,000 per year
Eczema (including hand eczema) 12%
Enzyme induced desquamation (peeling) Unknown
Ichthyosis (Vulgaris IV and 5 other types) Common
Familial Atypical (Moles) Very Common
Perioral Dermatosis 16%
Psoriasis 2%
Rosacea 5%
Scabies (Acarushunanus subcetaneus
insects and three other tiny
burrowing insects)
Uncommon
Seborrheic Keritosis
(“Cauliflower clusters”) 90%