08-16-2017, 08:38 PM
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What is a cosmetic?
In Australia, a cosmetic is defined under the Industrial Chemical (Notification and Assessment) Act 1989 as a substance or preparation intended for placement in contact with any external part of the human body' (this includes the mouth and teeth). We use cosmetics to cleanse, perfume, protect and change the appearance of our bodies or to alter its odours. In contrast, products that claim to modify a bodily process or prevent, diagnose, cure or alleviate any disease, ailment or defect are called therapeutics. This distinction means that shampoos and deodorants are placed in the cosmetics category, whilst anti-dandruff shampoos and antiperspirants are considered to be therapeutics.
Regulation and safety
In Australia, the importation, manufacture and use of chemicals including those used in cosmetics are regulated by the Australian Government s National Industrial Chemicals Notification and Assessment Scheme (NICNAS). NICNAS works to ensure that chemicals used in consumer products do not cause significant harm to users or to the environment.
In the case of cosmetics, every ingredient contained within the product must be scientifically assessed and approved by NICNAS before being manufactured or imported into Australia and before they can be used in consumer products. Where appropriate, NICNAS sets limits on the level at which a chemical can be used in a product and also conducts reviews on chemicals when new evidence arises.
Cosmetic products that make an additional therapeutic claim (such as moisturisers that also lighten the skin) are regulated by a different organisation the Therapeutic Goods Administration (TGA).
What do cosmetics contain?
There are thousands of different cosmetic products on the market, all with differing combinations of ingredients. In the United States alone there are approximately 12,500 unique chemical ingredients approved for use in the manufacture of personal care products.
A typical product will contain anything from 15 50 ingredients. Considering the average woman uses between 9 and 15 personal care products per day, researchers have estimated that, when combined with the addition of perfumes, women place around 515 individual chemicals on their skin each day through cosmetic use.
But what exactly are we putting on our skin? What do those long names on the ingredient list mean and what do they do? While the formula of each product differs slightly, most cosmetics contain a combination of at least some of the following core ingredients: water, emulsifier, preservative, thickener, emollient, colour, fragrance and pH stabilisers.
Water
If your product comes in a bottle, chances are the first ingredient on the list is going to be water. That s right, good old H2O. Water forms the basis of almost every type of cosmetic product, including creams, lotions, makeup, deodorants, shampoos and conditioners. Water plays an important part in the process, often acting as a solvent to dissolve other ingredients and forming emulsions for consistency.
Water used in the formulation of cosmetics is not your everyday, regular tap water. It must be ultra-pure that is, free from microbes, toxins and other pollutants. For this reason your label may refer to it as distilled water, purified water or just aqua.
Emulsifiers
The term emulsifiers refers to any ingredient that helps to keep unlike substances (such as oil and water) from separating. Many cosmetic products are based on emulsions small droplets of oil dispersed in water or small droplets of water dispersed in oil. Since oil and water don't mix no matter how much you shake, blend or stir, emulsifiers are added to change the surface tension between the water and the oil, producing a homogeneous and well-mixed product with an even texture. Examples of emulsifiers used in cosmetics include polysorbates, laureth-4, and potassium cetyl sulfate.
History
The appearance of skin care formulation dates to around 3000 B.C.E. in ancient Egypt. Most concoctions were prepared from natural materials. Cleopatra is said to have bathed in donkeys' milk to keep her skin smooth and supple. One naturally occurring material used by the ancients was red ochre, or iron oxide. Lumps of red ore were formed when iron oxidized or rusted. The red iron oxide was found in burial tombs in ceremonial lip tints and rouge preparations. It was also used to draw the ancient cave pictures of animals, as seen in Altimira, and is still used in many makeup formulations.
The Chemistry of Cosmetics
Cosmetics are an excellent example of how discoveries in chemistry are part of our day-to-day lives. In fact, just reading the composition of any common cosmetic can become a chemistry class: water, emulsifiers, preservatives, thickeners, pH stabilizers, dyes and fragrances, combined in different ratios, for different purposes.
The use of cosmetics that is, chemical compounds to improve our appearance is not a recent phenomenon. It is said that the Egyptian queen Cleopatra bathed in milk, as a way to keep her skin beautiful and soft. Which probably actually worked because it is proven that lactic acid one of milk s chemical compound acts on the deeper layers of the epidermis, promoting the removal of dead cells and skin renewal.
In ancient Greece, three thousand years before Christ, women used powdered lead carbonate to make their faces paler. Unfortunately, we now know that lead carbonate is toxic and it is possible that the pursuit of beauty cost the lives of some of these women.
In many cases, these different cosmetic products have a strong component of scientific innovation, developed in modern research laboratories. Suffice to say that the cosmetics industry was among the first to adapt the new features of nanotechnology through the use of nanoparticles to improve the quality of their products and satisfy the desires of its customers.