Green Chemistry Principles in Cosmetics
What exactly are sustainable and eco-friendly beauty products?
Green cosmetics also known as sustainable or eco-friendly cosmetics are designed with environmental impacts and safety to human health in mind. Even though putting organic and natural ingredients on the skin will not give the same level of effect as eating them (as we hope), it is still important to make our everyday products as sustainable and eco-friendly as possible. Not only what you put on your skin, but what goes into the ocean and the soil will come back in the food you eat.
So, what sustainable and eco-friendly beauty products should have and shouldn’t have? There is good guidance developed in 1988 by John W. Dower and Paul Anastas, The 12 Principles of Green Chemistry. This gives a broad but the directions that we need to look at.
When we go deeper than “non-toxic” “cruelty-free (not tested on animals)” “natural”, there are many examples that are not so green or sustainable as it sounds. For example, Argan oil has become popular and desirable ingredients especially for haircare products. The demands for oil production have pushed the Argan trees to become an endangered species. Another example is Sodium Benzoate which is often used in food and cosmetics as a preservative. It is nature identical but produced synthetically by partial oxidation of Toluene, which is commonly used in paint thinner and permanent markers. It is regulated to use at the max. 0.5% in leave-on cosmetic products and is classified as a generally recognized as safe by DFA (Food and Drug Administration). When it is combined with Ascorbic Acid (Vitamin C), it may form Benzene. In the U.S, there were beverage products tested and re-formulated because of the Benzene contaminant.
There are a lot to consider and limitations. The ingredients that are safe for us to use in cosmetics may still be harmful in the environment and come back to us later. Micro plastics are a good example. What about chemicals that react with other materials in landfills? What about workers in the manufacturing space who are exposed to a larger amount of chemicals every day? There are many more to understand. But following the Green Chemistry principles is a good place to find what is a better choice.
The goal of Green Chemistry
The main goal is to minimise or completely eliminate waste in the process of chemicals and the finished products. We would also need to minimise toxic material in the waste. In all industries from mining to agriculture, it is now clear for all of us that preventing the source of pollution is the solution rather than managing the pollution. Products should be designed to achieve this goal at all stages of their life cycle, including raw material extraction, production, transportation, consumption, and disposal.
There are limitations to applying these principles for cosmetic products.
- We would still need to make sure that products are compliant with regulatory standards. In many cases, using only natural ingredients or no preservatives are not possible.
- There is no definition of “organic” “natural” or “green” set on cosmetics by any regulations. Certificates issued by private organizations are inconsistent and hard to understand the actual credibility.
- Synthetic or highly processed ingredients are easier to determine the safety than unprocessed natural materials. Natural ingredients have many benefits to the skin, but they also have many substances that are toxic or allergens. They can contain hundreds of different substances and it is very hard to tell which one is good without enough evidence from studies. Synthetic ingredients have a very small number of substances because they are highly purified, and usually have plenty of studies done to prove the safety and efficacy.
- Favouring natural over synthetic can harm the environment. For example, Bakuchiol is now known as a natural/clean version of Retinol and gained a lot of attention. It is extracted from the seeds of the Babchi plant grown in India. This plant was already at risk of extinction back in 2017. In 2018, British Journal of Dermatology published a clinical study that promoted bakuchiol as a natural alternative to retinol without the risk of side effects. The bakuchiol boom caused not only the Babchi plant further in danger, but also other medicinal plants growing in the same region are facing threats of overexploitation and biodiversity depletion.
As we tend to look at only one problem at a time and cause unexpected consequences, we need to pay attention to what is happening in the whole chain to create the product.
Principles of Green Chemistry
Here, we discuss some of the 12 principles that are relevant to all of us. If you would like to explore the rest of the principles, visit HERE.
Design products and production processes to minimize or eliminate the waste.
It is no brainer that eliminating the waste and the cause of pollution is far better than dealing with the waste and pollution with extra costs. Waste in the life cycle of beauty products would be water (for cleaning equipment, in the finished product, consumption, disposal), energy, ingredients, packaging, etc. Pollutants would be wastewater, evaporated or spilled chemicals, unused ingredients/products sent to landfills, and packaging.
One of the ways to measure waste is the ratio of the weights of all materials used to the weight of the active ingredient produced.
Atom economy is a measure of how much of the starting material is converted into the desired functionality of the finished product.
One obvious example is water. Many liquid cosmetic products have up to 80% water as solvent in them. It is not an active ingredient because it does not do anything to the skin. If the product can deliver the same function without water, it reduces at least 80% waste.
Less Hazardous Chemical
Safer chemicals are those that have a low hazard rating as determined by the Globally Harmonized System (GHS). A chemical's hazard rating is based on its physical and toxicological properties, as well as its flammability. All chemicals have hazards, even water. But some have higher ratings than others due to their inherent toxicity or easy reactivity with other chemicals during manufacturing processes.
The safety of cosmetic ingredients for human health has been tested and the usage limit is well regulated. So, you don’t need to worry too much about safety. However, the research on the safety of many of those for other species and the environment is still at the beginning.
Designing Safer Chemicals
While reducing toxicity, the products still need to preserve their effectiveness and safely.
For example, preservatives are undesired ingredients for most of us. They are often talked about as unsafe and irritating ingredients. Some say it is unnecessary. However, it is necessary to preserve the cosmetic product unless you are going to finish it all in the same day, or the product does not have water. Wherever there is enough water, microorganisms will grow within a few hours to a few days.
It is challenging to make functional products with completely no toxic chemicals. But we see good progress in the industry.
As you know, energy consumption is the biggest cause of climate change.
Cosmetic chemists who develop the recipe to make beauty products focus mainly on the performance of the products on the skin. But it is important to consider the manufacturing and disposal processes in mind to reduce the usage of heat and hours of machine operations.
Packaging is the most discussed topic around sustainability in the beauty industry. But there are more efficient ways to reduce carton emissions such as processing ingredients at lower temperature or with no heating at all. Reducing the weight and volume of finished products can dramatically reduce the energy consumption per product for packaging, transportation, and waste management.
Using Renewable Feedstock
In the original principle, it suggests that all raw material or feedstock should be renewable. Use biofuel made from corn or palm rather than fossil fuels, for example. However, we don’t have enough habitable land and water to grow enough plants to replace the amount of fossil fuels we consume. We currently have only less than 1% of plastics made from renewables and the rest is still petroleum products. While we have been trying to end non-renewable sources, renewables such as trees, fish, and animals are disappearing.
There are ingredient manufacturers producing natural materials from wasted food instead of growing plants for chemicals. Another solution is to synthetically produce nature identical chemicals that are from sustainable sources and no impact on the environment. This will reduce the pressure on the natural environment while keeping the efficacy.
Reduce Production Processes
When processing raw materials to make cosmetic ingredients, there will be waste. Sometimes the byproduct can be another usable product. For example, the byproduct of Rose Essential Oil is Rose Water (Hydrosol). However, it is better not to have the waste in most cases. Cosmetic ingredients go through many processes, cleaning, heating, milling, pressing, chemical reactions, etc. If the ingredient contains water, it will need preservatives as well.
To just give an idea, we need 583 kg (1285 lb) of Rose petals to make 450g (1 lb) of Rose Oil. It takes a lot of raw materials and processes to extract and produce ingredients.
Wherever possible, choose the way to produce ingredients or finished products with less processes.
The concepts from Green Chemistry can help us to improve our beauty products with long-term solutions to be responsible for the environment and our health. There is no one solution for all issues, water conservation, reduction of carbon emissions, minimum impact on the environment, human health, waste reduction, etc. Instead, our mindset to always look for better solutions and willingness to take actions is the key to achieve these goals. It is not only for chemists to formulate or brands to design products. Each of us as a consumer needs to demand the move. When it comes to our own health and our living environment, we need to initiate change.
Green cosmetics: perspectives and challenges in the context of green chemistry - https://www.researchgate.net/publication/340958580_Green_cosmetics_perspectives_and_challenges_in_the_context_of_green_chemistry
Sodium Benzoate - https://en.wikipedia.org/wiki/Sodium_benzoate
12 Principles of Green Chemistry - https://www.acs.org/content/acs/en/greenchemistry/principles/12-principles-of-green-chemistry.html
Psoralea corylifolia L: Ethnobotanical, biological, and chemical aspects: A review - https://www.researchgate.net/publication/321855975_Psoralea_corylifolia_L_Ethnobotanical_biological_and_chemical_aspects_A_review
Using the Right Green Yardstick: Why Process Mass intensity Is Used in The Pharmaceutical Industry To Drive More Sustainable Processes - https://pubs.acs.org/doi/10.1021/op200097d
The Twelve Principles of Green Chemistry - https://www.compoundchem.com/2015/09/24/green-chemistry/