Squalene for Skin Care
What is
Squalene?
This natural treasure from the deep, cold waters
of the South pacific, was discovered in 1906 by Dr. Tsujimoto of Japan.
However, extensive medical research did not begin until 1930, when it
was noted that sharks do not develop tumors and are cancer free.
Squalene is an extract of shark liver oil from the Aizame shark whose
natural Pacific habitat is in unpolluted ocean depths of 3,000 feet in
35 degree waters.
The centrophorus artomarginatus deep
sea sharks live in waters 600 to 1000 m deep, without sunlight. How can
they manage to survive under such harsh conditions, where pressure is
consistently high and oxygen supply is very poor? The secret lies in
their livers, which account for 25% to 30% of their total body weight.
Identified as Squalene, with a chemical formula C30H50,
Squalene is an unsaturated hydrocarbon, which can easily produce oxygen
by combining with water. Squalene has been extensively researched and,
as an oxygen carrier, found to play a key role in maintaining health.
Dr. Noguchi once said that "the cause of all
illnesses is lack of oxygen."
A curious trait of the shark is its apparent
immunity to cancer and disease. Once regarded as an enemy, a primitive
and powerful hunter of the deep, the shark in now being heralded as a
lifesaver.
This unique fish which has remained structurally
unchanged for 400 million years, may provide us with the natural
resistance we need to fight many of our most common modern diseases
from colds to cancer.
Another source of Squalene is olive oil, which
has been traditionally known for its health effects.
A related compound is Scalene used in skin care
products. Squalane is derived from Squalene, but is more stable against
oxidation.
Other very useful properties of Scalene is its
very low coagulation point (-55 degrees Celsius) and very high melting
point (203 degrees Celsius), making it very suitable for lubrication.
Properties of Squalene
Detail description of the properties and uses of
Squalene and Scalene can be found in: "Biological Role and
Practical Uses of Squalene and Scalene" by Maurice L. Rosenthal
in "COSMETICS AND THE SKIN" by I. Lubowe and F.V. Wells,
editors Reinhold Publishing Corp., 1964.
The following are excerpts from the above
article:
Squalene (C30H50)
"The triterpene Squalene is a highly unsaturated
aliphatic hydrocarbon (C30H50) which is widely distributed in nature.
It is found in small quantities in many vegetable oils, and in larger
amounts in certain fish oils. Interest in its medical and
cosmeto-dermatological significance was intensified when Squalene was
found in human sebaceous secretions, as a precursor of cholesterol, and
when its possible anti-carcinogenic effect was described. It is the
principal hydrocarbon of human surface lipids amounting up to 11 per
cent of total surface fat. Its occurrence has been reported in dermoid
cysts, cerumen, hair fat, and sebum.
In attempting to assign a specific role to
Squalene in biochemical processes, many interesting developments took
place. Squalene, a byproduct of natural Vitamin A commercial
production, also is converted on its biochemical path to cholesterol
synthesis, into 7-dehydrocholesterol, which on irradiation becomes
Vitamin D. The very limited percutaneous absorption of Vitamin A in
enhanced when the vitamin is dissolved in Squalene
Studies in relation to its presence in ovarian
dermoid cysts and depot fat of women led to its identification in
vernix caseosa. It was then postulated that Squalene plays an important
part in embryological development.
Investigation of the fungistatic effect of sebum on skin surfaces led
to the observation that certain carcinogenic chemicals are inactivated
when exposed to Squalene over a period of time.
Further studies on patients with epidermoid
carcinoma suggested that Squalene served as a protective agent in human
sebum, as this is the usual type of carcinoma which arises after
exposure to carcinogenic hydrocarbons, excessive exposure to sunlight,
and ultraviolet rays."
Sebum
"Sebum provides the normal lubricant of hairy and
no-hairy skin. It keeps the skin supple and forms a protective
bacterial and fungicidal coating on the skin and in the pilosebaceous
apparatus. This fatty cover helps to keep moisture on the skin surface."
Squalene occurs naturally in the human sebum.
When human sebum was separated from epithelial lipids, its average
composition was calculated as follows:
| Free fatty
acids |
5%
|
| Glycerides |
50%
|
| Waxes |
20%
|
| Squalene |
10%
|
| Other
hydrocarbons |
5%
|
| Cholesteryl
esters |
4%
|
| Cholesterol
(free) |
1%
|
| Other sterols |
1%
|
| Other
substances |
4%
|
Penetration through
the Skin
"The topical application of medicaments to the
skin forms the basis of most dermatological therapy. Such application
has many advantages, such as absence of pain and of bad taste,
simplicity and ease of administration, and high concentration at the
desired site. It is the only method by which a high local concentration
of drugs in the skin can be achieved without undesirable systemic
side-effects.
In many instances, it would be advantageous if
the rate of penetration of medicaments through the epidermis could be
increased. This would help in bringing about a more rapid and profound
action of the locally applied compounds. If penetration
(transfollicular, transepidermal, and into the horny layer) could be
increased, many new compounds could be introduced into therapy.
Hence, the importance of sebum and its main
hydrocarbon Squalene in cosmeto-dermatological field. The commercial
use of this unique hydrocarbon was, therefore, a forgone conclusion."
Scalene (C3H62)
"This commercially available product is a
colorless, odorless, tasteless, transaparant, stable, inert,
homogeneous liquid oil." "On the basis of numerous clinical tests, it
has been concluded that Squalene is a bland vehicle, with the unusual
property to increase the rate, depth, and extent of penetration of
topical agents from medicated ointments. On the other hand, squalene
does not aid transepidermal penetration, nor dissolve the cementing
substance of the horny layer."
"The cosmetologist has found in Squalene a
natural emollient. It imparts to the skin a suppleness without an
unpleasant greasy feel. It readily forms emulsions with fixed oils and
lipophilic substances and does not oxidize nor turn rancid. Scalene has
also been found to accelerate dye-dispersion in lipsticks, producing a
high gloss and acting as a long lasting fixative for perfumes.
When applied to washed or sun exposed skin and
hair, squalane helps to restore the lost oils. It has long been known
that coating the skin with oils offers considerable protection from
sunburn because of a strong absorption band in the erythemogenic region"
Cosmetic Ingredient
Review
Scalene and Squalene have been identified as a
natural components of human sebum. Both ingredients are used at
concentrations ranging from =< 0.1 to >= 50 percent in a variety
of cosmetics. Because cosmetics containing Scalene and Squalene are
applied to all body surfaces, these compounds may potentially enter the
body through the skin, eyes, lungs, mouth, or other routes. Squalene
can form peroxides on exposure to air, while Scalene is stable to air
and oxygen. Animal studies indicate Scalene is slowly absorbed through
the skin, while both compounds are poorly absorbed from the
gastrointestinal tract. Squalene is a metabolic precursor of
cholesterol and other steroids.
The acute toxicity of these ingredients by all
routes in animals is low. At 100 percent concentrations, both compounds
are nonirritant to rabbit skin and eyes. According to clinical evidence
of formulations containing Scalene, the compound is not a significant
skin irritant or sensitizer.
Limited contact sensitization tests indicate that
Squalene is not a significant contact allergen or irritant. Reversible
depilation is reported from topical application of Squalene to animals,
but limited human studies did not show any such effect. No
photosensitivity data for the two ingredients were available.
Conclusions
On the basis of the available information presented
in this report, The Expert Panel concluded that both Scalene and
Squalene are safe as cosmetic ingredients in the present practice of
use and concentration.
Source: Second Report of the Cosmetic Ingredient
Review Expert Panel Journal of the American College of Toxicology
(Special issue) Volume 1, Number 2, 1982, Pgs. 37-56.