There are differing views and interpretations of the naturals and organic markets, what makes a material natural or what prevents a product from being truly natural. To start with a definition, natural is what is found in nature, anything that comes from the vegetable, mineral and animal worlds. As we know most of the natural materials found in nature are not ready to use as such and they therefore need to be processed using different techniques:
• pressing seeds and oily fruit to produce vegetable oils and fats (ideally cold processing in order to retain vitamins, sterols, tocopherols, carotenoids, etc), and pressing of citrus peels to make citrus oils
• steam distillation of plant material to make essential oils and hydrolats
• maceration, an extraction process where plant material is infused in vegetable oil, left to macerate for some time and then filtered out to give a very gentle extract
• filtration, for example beeswax needs to be melted and filtered to remove wicks and other foreign materials
• natural fermentation and distillation to make ethanol
• solvent extraction using vegetable derived ethanol and water to make herbal tinctures
Given this very basic natural definition, available to formulators are: vegetable oils and fats, salt, sugar, essential oils, hydrolats, maceration oils, beeswax and other bee products, ethanol, alcoholic herbal tinctures, animal fats such as lanolin, lye (lime was originally used) and clays. As there are no preservatives involved, apart from the ethanol, the majority of the products which can be obtained are water-free ones, such as massage oils, face oils and balms, traditional soaps, face and body mud made of water and clay, eaux de toilette and face toners based on hydrolats and tinctures. These products are quite easy to formulate as they contain just one phase.
There are several balms on the market that are being used as face cleansers, day and night moisturisers, cleansers, body butters, body scrubs and baby balms. Despite the fact that oil-based products can feel oily and perform differently from mainstream cosmetics, they are becoming more popular and are used for the body as well as the face. Facial toners preserved with ethanol are not so popular and the author is not aware of any currently available on the market, whereas there are facial toners based on hydrolats and alcohol-free. Natural edts are not common products in the marketplace as their performance is not comparable with their synthetic counterparts because of the lack of a strong natural fixative and the much smaller natural scent pallet. Energies need to be invested in this field to educate the general public to understand and accept the performance of natural edts.
In order to move into the second generation of natural cosmetics by introducing water and emulsions we need to look into the minefield of natural derivatives and preservatives, to see how natural raw materials can be modified and extracted by using modern chemical and biotechnological processes. The simplest chemical reaction is based on breaking a bond to form a new one giving a new chemical, which still contains part of the natural structure of the first raw material. An example is the saponification of oils where the alkaline hydrolysis breaks the triglycerides giving fatty acids and glycerine. In the same line there are other chemical processes such as condensation and esterification with other natural materials.
Hydrogenation is a tricky process as it is usually performed using nickel as a catalyst instead of the more expensive platinum and palladium, so there can be issues about the involvement of a heavy metal. The British organic certification bodies - the Soil Association and the Organic Food Federation - do not allow hydrogenated raw materials in their beauty standards, whereas the French Ecocert and the German BDIH do. The advantage of allowing hydrogenation is that it increases the selection of raw materials available to the formulator, giving materials which are stable to oxidation and which have an elegant skin feel. The downside is a loss of purity because of the catalyst used and the isomerisation and other reactions that can take place. The different positions on hydrogenation demonstrate the lack of a universal guideline to assess chemical processes and the resulting products. The way certifying bodies work with this is to assess the manufacturing process by looking at several parameters of the reagents involved, allowing some petrochemicals in the reaction providing they are not carcinogenic and that no detectable traces are left in the final material. There are also bioaccumulation, biodegradability, aerobic as well as anaerobic and water toxicity parameters for the finished material to evaluate such as EC50 daphnia, LC50 fish, IC50 algae, and OECD tests. Each organisation sets its own maximum limits for these parameters, so there may be discrepancies among them. But the essence of looking at these parameters is to ensure that the environmental impact of chemical processes and their products is kept to a minimum and that the products themselves are safer by using stricter limit thresholds than common safety standards. This explains why organic certification bodies do not accept the use of radiation and GMO materials; there is insufficient scientific evidence available proving that it is safe to use radiated and GMO materials, plus GMO environmental impact has yet to be fully investigated.
Accepted processes
Thanks to the compromise on the use of some chemical reagents, the acceptance of processes based on the use of micro-organisms and modern separation techniques such as molecular distillation, critical CO2 extraction and vacuum distillation, the green cosmetic formulator has access to a much wider array of materials:
• emulsifiers that are vegetable derived and which have a good stability performance, such as sucrose esters, fatty alcohols, glucolipids and other naturally derived esters
• humectants, glycerine being the most commonly used
• actives, which are dry, in glycerine, ethanol, vegetable oil or water (preserved with accepted preservatives)
• rheological modifiers, alginates, carrageenan and other natural gums
• mineral and plant derived colours
• antioxidants, such as tocopherols and many other plant extracts
• chelating agents, for example phytic acid
But there are still no natural alternatives to antifoaming agents, so emulsions made with natural emulsifiers may cream and lack the silky feeling obtained with silicones. Luckily in the last few years the industry has released new emulsifiers with lighter skin feel, but they are more expensive than traditional vegetable emulsifiers based on fatty alcohols and glyceryl stearate.
The weakest links
Preservatives and surfactants are the weakest points when it comes to formulating naturally. There are natural preservatives on the market and several finished products using them, but it requires time to get to know them as they can be affected by pH, essential oils and other factors or they may affect emulsion stability. They may also only be effective with certain micro-organisms, requiring some extra synthetic help, or they can have strong odours or colours spoiling the look and performance of the natural formulation. While many natural materials have a long history of use, natural materials as preservatives are fairly recent and there is much less history about them. Given this complexity and the need for the products to be safe, the organic certification bodies decided they had to allow some purely synthetic raw materials, and different organisations decided to permit different preservatives. The preservatives usually accepted in organic products come either from the food industry or from chemicals found in essential oils, sorbic acid and its salts, benzoic acid and its salts, benzyl alcohol, phenylethyl alcohol and phenoxy ethanol. On the European continent formic acid, propionic acid and salicylic acid are also accepted. This again underlines the lack of harmonisation between organisations, adding another challenge for the natural or organic formulator.
There is one preservative on the market that sounds natural and that has a good toxicity profile and activity, but which has a mode of action based on donating a formaldehyde precursor: sodium hydroxymethylglycinate.
For this reason it is not allowed in Japan. Selecting materials for formulating can be a really tricky business and requires a lot of questions to raw materials suppliers who need to provide a considerable amount of information, not only on the properties of the raw material but also on its manufacturing and processing methods.
The most natural surfactants are plant derived saponins, which usually give brown solutions with no rheological properties. They therefore have to be combined with other surfactants coming from more complex processes to improve their performance. The British certification bodies have only approved the use of a few surfactants and there are very few rinse-off products on the market that are organically certified. It is still a grey area and a lot of work needs to be done to increase the choice of raw materials, the main problem being increasing the system viscosity while still retaining rheological behaviour comparable to similar products on the market. It is probably just a question of time until it becomes easier to work with surfactants to make pleasant and effective products. It is an area of huge potential and clever and creative raw materials suppliers may well come up with new and appropriate materials in the near future.
Natural futures
The author is positive about the future of natural raw material availability and selection because suppliers have started to provide actives made from organically certified plants, such as Gatuline RC Bio from Gattefosse and the Gemmo Blasts range from Jan Dekker International, enabling the formulation of more effective natural products. Plant derived actives diluted in synthetic solvents or preserved with parabens look more contradictory than ever before and hopefully more suppliers will understand that and act upon the market need and trend towards more natural ingredients.
Today it is possible to formulate a natural version of most cosmetic products, with a pleasant sensorial performance, good stability, good efficacy and safety. But it is not easy and is a specialist job, the main challenges being:
• the higher cost of organic raw materials and their availability
• shorter shelf life of finished products
• a smaller actives selection
• lack of harmonisation of organic standards
• the different performance achieved with naturals
• the restriction of raw materials available in general
• ensuring raw material purity, ie free from contaminants not declared in the INCI breakdown
Formulating naturally is very much a question of balance in between the environmental aspect, the product performance and price.
Being a purist can affect product performance, allowing only mono-phase systems which mass consumers are not used to or familiar with, despite the increase in popularity in the last few years.
Being more determined to get the performance right can involve the use of raw materials which are hydrogenated or contain petrochemical parts so that the purity of the finished product is missed.
Being stuck on price means maybe coming up with a pure product but with not much activity as cheaper organic ingredients are used, such as organic sunflower oil with a squirt of organic almond oil.
The secret is the fine balance between those elements in order to provide a modern natural cosmetic product that is pure in its ingredients, safe, pleasant, effective and in harmony with nature.
For this reason the author believes it is important to avoid petrochemicals (propylene glycol, mineral oils and other organic solvents in general), silicones, ethoxylated and propoxylated materials, even if partially of natural origin, parabens and other major synthetic preservatives, carbomers, acrylates, GMO materials, synthetic fragrance, hydrogenated ingredients, synthetic colours, synthetic chelating agents and antioxidants.
Formulating with naturals and organics is a huge and complex subject that can get quite personal as anybody can form their own interpretation. This article touches on and simplifies major subjects in an attempt to provide a technical general view. It is also the result of seven years of experience in this field as a formulating chemist and of a personal passion for natural ingredients. Opinions are most welcome.