3.4 The science behind cosmetics

As you learned in an earlier module, the Ancient Egyptians were sophisticated chemists and had worked out that Kohl had antibacterial properties and helped protect their eyes from the sun. It is only through the progression of science that products such as Kohl were swapped out for safer products with out any nasty metals or contaminants.

Cosmetic science is a science in its own right, and it includes the study of the development of products to improve our hair, skin, nails, and body. The cosmetic industry is a big business, so there are cosmetic scientists all over the world studying and formulating new concoctions every day. These days, nearly all products will have their own unique formulation to meet the desired purpose. Back in the 1920s, there were limited options, whereas now, we can pick up products in all colours and formulations. The timeline below provides a snapshot of when products were first released:

As you can see from the timeline above, hairspray wasn’t even a thing until the late 1940s! You might also be surprised to know that aerosol deodorants weren’t available until 1965, and it was in 1989 that a safe teeth whitening product was available.

If you are interested in learning more about cosmetics, access the resources linked:

Every product on the market today has a history, and there was a lot of trial and error to get it to the quality it is today. If you remember from earlier, fifteen women went blind, and one died from reactions to para-phenylenediamine in a lash product in 1933. Thankfully today, selecting cosmetics is not a life or death choice because science has evolved, and the industry is regulated.

In Australia, the Australian Government’s Australian Industrial Chemicals Introduction Scheme (AICIS) regulates the importation and manufacturing of chemicals. This means that every ingredient in a cosmetic product must be scientifically assessed and approved by AICIS before it can be sold. AICIS was formerly the National Industrial Chemicals Notification and Assessment Scheme (NICNAS), and this changed in 2020. For any cosmetics which claim to have a therapeutic claim, such as skin lightening, these are regulated by a separate government body- the Therapeutic Goods Administration (TGA). In terms of product safety and labelling, this is managed by the Australian Competition and Consumer Commission (ACCC).

If you are interested in learning more about these regulators, checkout their websites:

In addition to regulating the industry, requirements for testing have also developed over the years. For decades now, big brands have been testing cosmetics on animals as part of their product development process to determine whether or not products are safe to use. Of course, subjecting animals to rigorous testing is inhumane, but it still happens around the world. Some people argue that it is better to test on animals rather than testing potentially unsafe products on humans. Currently, cosmetic animal testing is banned in Colombia, the European Union, the United Kingdom, India, Israel and Norway. On July 1st, 2020, Australia implemented a ban on cosmetic testing on animals after strong public support.

While the ban is a step in the right direction, it only applies to new products, so any cosmetics which already exist on the market are not affected. This means that big brands can still test on animals in other countries and sell their goods in Australia. In addition to this, the way the legislation in Australia is written, it has created a loophole whereby ingredients used for multiple purposes (not solely cosmetics) can be tested on animals. Some of the major brands on the market test on animals, so if this is something you want to avoid, you should conduct research into cruelty-free products before stocking your kit. If you would like to learn more about the impacts of animal testings, access the resources linked:

If you are interested in learning more about these regulators, checkout their websites:

Common makeup product ingredients

If you have ever looked at the ingredients list on any of your beauty products, it may look like they are written in another language! As a professional MUA, it is absolutely essential that you know and understand all of the ingredients in your products and how they might react with other products. The key ingredients present in most cosmetics include water, emulsifiers, preservatives, thickeners, moisturisers, colours and fragrances. Depending on the formulation, ingredients can be synthetic (made by humans) or natural (made by nature). The table below provides an overview of the main ingredients in cosmetics:

WaterAqua or water is in nearly all cosmetic products. Purified water is essential in most product formulations as it acts as a solvent to dissolve other ingredients. Mixing water with other products can also form emulsions for consistency.
EmulsifiersEmulsion occurs when small droplets of one solution (which is often oil-based) are dispersed throughout another (which is often water-based). Emulsifying agents work with oil and water-based solutions to homogenise the mixing process to achieve the desired texture. Common emulsifiers are polysorbates, laureth-4, and potassium cetyl sulphate.
PreservativesPreservatives are added to products to help preserve shelf life and to reduce microbial contaminants. The most common preservatives used in cosmetics include parabens, formaldehyde releasers, isothiazolinones, phenoxyethanol and organic acids.
MoisturisersAny product that is left on the body for any period of time has an opportunity to enrich the skin and the skin condition. Many products will use ingredients to help boost moisture. Some compounds that provide moisturising effects are polysaccharides, proteins, acids and small molecules like aloe vera, glycerin and sorbitol.
ThickenersThickeners do what the name suggests; they can thicken up products to achieve a range of consistencies. Thickeners can be completely natural like waxes but also synthetic. Thickeners can also act as moisturisers because many can retain water. If you see polysaccharides, proteins, alcohols, silicones, or waxes on your ingredients list, they are likely thickening agents.
ColoursWhen it comes to the colouring of cosmetics, additives can be categorised as organic and inorganic. Now, this is not to be confused with synthetic or natural. Organic and inorganic can both have natural products; it just refers to the compound structures. The three main types of organic colour additives are synthetic dyes, lakes, and botanicals. In terms of inorganic colour additives, these are made from mineral compounds such as iron oxide and zinc oxide. Both organic and inorganic additives can then be classified as dyes or pigments. The main difference between dyes and pigments is that dyes are water-soluble, while pigments are oil dispersible.
FragranceFragrances in cosmetics can be synthetic or natural. Many brands will add in fragrances to help ensure products smell nice, and they can be great marketing tools. Some brands have formulations that smell like chocolate, coconut and various fruits. Many companies are actually allowed to just use words like parfum, eau de toilette or simply fragrance rather than listing ingredients. The reason for this is that fragrances are considered to be trade secrets, so they don’t have to list them! A common ingredient that will be in a lot of cosmetics is Phenethyl Alcohol. Phenethyl Alcohol is used in so many products, from shampoos, lipsticks, deodorants and creams. The reason products use Phenethyl Alcohol is because it is a preservative and fragrance ingredient and tends to have a floral and sweet odour.

The ingredients above are not exhaustive but should give you an idea of the sorts of typical ingredients to look out for. Cosmetic chemistry is a science in itself, so you are not expected to know every single ingredient off by heart. So, if you are unsure of what an ingredient is, you can:

  • Ask your supplier
  • Read the ingredients on the packaging
  • Request the safety data sheet (SDS)
  • Use good old google!
  • Purchase a cosmetics dictionary or access one online

As an example, let’s take a look at the Lucas Papaw ointment. This product is found in many Australian households as a bit of a cure-all product for dry lips, chaffing, sunburn and nappy rash! Look at each of the ingredients, and research any that you do not know using google or an online dictionary like the one here Ingredient Dictionary.

Lucas Papaw Ointment


Asimina Triloba Fruit Extract, Rhus Succedanea Wax, Glycerine, Petrolatum, Canola Oil, Hydrogenated Castor Oil, Beeswax, Corn Starch, Potassium Sorbate (0.1 Mg/​G).

How did you go with your research? The image below explains what each ingredient does:

Ingredient nameWhat does it do?
Asimina Triloba Fruit Extracthealing enzymes of papaw
Rhus Succedanea Waxviscosity controlling
Glycerineskin-identical ingredient, moisturiser/​humectant
Canola Oilemollient
Hydrogenated Castor Oilemollient, viscosity controlling, emulsifying, surfactant/​cleansing
Beeswaxemollient, viscosity controlling, emulsifying, perfuming
Corn Starchviscosity controlling, abrasive/​scrub
Potassium Sorbate (0.1 Mg/G)preservative

As people become more health-conscious, many of your clients will want to know the ingredients in the products you are using. One area of concern in recent times relates to the use of ‘parabens’ in cosmetics. Parabens are additives that many manufacturers add to products to extend shelf life. Further studies into the use have parabens have indicated that they can disrupt hormone levels, and some say they are linked to cancers. Studies into certain ingredients are still ongoing, and you will likely find many articles that will say these concerns are myths and others that say they are completely safe. If you and your clients are health-conscious, opting for more organic and natural products is the way to go. But remember, the fewer preservatives your products have, the smaller the shelf life!

If you are interested in learning more about different ingredients in cosmetics and ones to avoid, access the resources linked:

Product reactions – oil, water and silicone

Now that you have a general understanding of the common ingredients in makeup and their purpose, we will finish this lesson off by briefly looking at product reactions that may occur, specifically relating to water-based and oil-based products. If we use a moisturiser as an example, you will see that there are water-based and oil-based products available. As you may have already worked it out based on the emulsifying process you learned about earlier, an oil-based moisturiser means that ingredients have been dissolved and an oil base and vice versa for water-based products.

If you mix products that have oil bases and water bases, you may find that you could experience a separation of products, flaking or less longevity. A common culprit for this reaction is the reaction between skin primers and foundations. Primers and foundations are either silicone, water or oil-based. When applying these products, it pays to look at the ingredients list to work out what base you are working with. As a general rule, remember the following:

  • Oil and water don’t mix
  • Oil and oil do mix
  • Silicone and water don’t mix (that well)
  • If your foundation is oil-based, then use a moisturiser that contains oil in the first few ingredients on the bottle
  • If your foundation contains silicone (most likely), then make sure that silicone is in your primer and/or moisturiser

Generally, water-based products are great for people with dry skin. If you have naturally oily skin, silicone-based products might be the most suitable because they are great at mattifying the skin and controlling shine.

Did you know: When Technicolor film (colour motion pictures) was introduced in the 1930s, Hollywood makeup entrepreneur Max Factor decided to develop a new powder formula, aptly named Pan-Cake, to overcome the challenges of greasy skin caused by grease paint used. It was water-based makeup and contained a myriad of pigments and oils that were dried and crushed to create a loose powder.

If you are interested in learning more, access the resources linked:

This site is registered on wpml.org as a development site.