Page 234 - Cosmetology

oil, to have antibacterial properties. It may cause skin irritation.

melamine. Derived from urea, it is used as a film-forming agent. See film-forming agent.

melanin. Pigment in cells that creates the color in skin and hair.

melasma. Melasma or chloasma are brownish discolorations of the face, hands, chest, and neck.
Pregnancy is a common cause of melasma, as well as taking oral contraceptives. However, unprotected
exposure to sunlight is also a major cause.

Melia azadirachta. See neem extract or oil.

melibiose. Saccharide that can have good water-binding properties. See mucopolysaccharide and natural
moisturizing factors.

Melissa officinalis. See balm mint extract and counter-irritant.

Mentha arvensis. See cornmint.

Mentha piperita. See counter-irritant and peppermint.

Mentha spicata. See counter-irritant and spearmint oil.

Mentha viridis. See counter-irritant and spearmint oil.

menthol. Derived from peppermint; it can have the same irritating effect as peppermint on skin. See
counter-irritant, and peppermint.

menthone. Major constituent of peppermint. See peppermint.

menthyl lactate. Used as a cooling agent and fragrance in cosmetics. It is a derivative of menthol and is
supposed to be less irritating than menthol. See counter-irritant and menthol.

methanol. See alcohol.

methionine. See amino acid and antioxidant.

methoxypropylgluconamide. An alpha hydroxy acid that may be less irritating than glycolic acid and lactic
acid. However, there is almost no research about this ingredient and very little is known about its benefit and
function.It most likely functions more as a water-binding agent than anything else. This ingredient was
originally patented by Revlon and the study cited above was carried out by Revlon.

methyl gluceth-20. Liquid that functions as a water-binding and skin-conditioning agent.

methylchloroisothiazolinone. In combination with methylisothiazolinone, it goes by the trade name Kathon
CG. Introduced into cosmetics in the mid-1970s, it elicited a great number of sensitizations in consumers.
This led to its withdrawal from cosmetics other than in rinse-off products.

methyldibromo glutaronitrile. Formaldehyde-releasing preservative.

methyldihydrojasmonate. Synthetic fragrant components.

methyleugenol. Natural constituent of such plant oils as rose, basil, blackberry, cinnamon, and anise.
According to the November 9, 1998, issue of The Rose Sheet (an insider cosmetics industry newsletter), the
National Toxicology Program Board of Scientific Counselors concluded that "methyleugenol, a component of
a number of essential oils, has shown clear evidence of carcinogenic activity in male and female rats and
mice." The study is an animal model and so the results may or may not be applicable to humans.

methylisothiazolinone. Preservative that should be used only in rinse-off products because it can be too
irritating when left on skin. See methylchloroisothiazolinone and preservatives.

methylparaben. See parabens and preservatives.