List of ingredients avoided for no good reason (as a marketing tool).

Dweck Data Research Notes


Anthony C. Dweck BSc CChem CSci FRSC FRSPH FLS


I am a chartered chemist, chartered scientist, Fellow of the Royal Society of Chemistry, Fellow of the Linnean Society of London and Fellow of the Royal Society for Public Health. You can take the opinion of somebody with almost 50 years in the cosmetic and toiletry industry and a fully qualified safety assessor or the word of somebody who may not have any qualifications at all.


I started on the quest for naturals as a chemist working on Mary Quant Special Recipes range in the early 70s, so I was in the naturals business long before most of you! The first paper ever given to the scientific industry was mine to the Society of Cosmetic Scientists May (1989) Lecture and preprint to the London Symposium. "Natural Ingredients - Fact or Fiction?" and Mr Peter Jarvis of Peter Jarvis Cosmetic Developments gave the second. The first retailer to sell a natural range was Marks & Spencer with the Extracts from Nature range and that was my idea too. So I am a keen fan of naturals and have published 100 papers, given the same number of lectures and published numerous book chapters on the subject. Our new books. Handbook of Aromatherapy. Handbook of Cosmetic Ingredients – their use, safety and toxicology. Handbook of Formulating Natural Cosmetics. Handbook of Natural Ingredients hopefully demonstrate how much I love the topic.


Natural products are far from safe – the shell of castor beans contains ricin and the death of Georgi Markov is testament to the toxicity of this material which comes from the same plant that provides castor oil. The toxicity of hemlock, deadly nightshade, strychnine (from Nux vomica), vincrastine and vinblastin from Madagascan Periwinkle or taxol from Pacific yew (chemotherapy drugs) show exactly how toxic naturals can be.


The full legal requirements for product safety are embedded in law. The law has six annexes which tell you the materials you cannot use, those that are restricted and those that are permitted for use as preservatives, suncreens or colours. If they are not in the annex then they are illegal for use in that role – unless you can justify an alternative reason for their use. This legislation can be downloaded from the web site.


In addition to all the laws there are also other bodies that look at the raw materials we use in our industry.

The Scientific Committee for Consumer Products (SCCP) in Europe

The Cosmetic Ingredient Review Panel (CIR) in USA

The perfumery industry has their ingredients scrutinized by RIFM and IFRA


Dweck Data are not alone in collecting the test data from animal testing in the past. It would be mad not to collect this information and use it as a bench mark for safety with those old and historic raw materials. Nobody liked the idea of sacrificing animals, but what happened in the past should not be wasted and we hold these results with respect. All materials are now tested using in-vitro tests which are more akin to microbiological test and which use human skin cell replicas to study the reaction. Knowing the historic animal data and using this in comparison to the modern tests we are now able to benchmark all new raw materials.


Many products are tested on human skin in the Repeat Insult Patch Test (RIPT).


As safety assessors and toxicologists it would be financial suicide to sign off the product safety report required by law if the product was not completely and totally safe. We do get tired of non-technical and uninformed people making the most ludicrous of claims when there is so much truth and scientific fact to be had.


Trading Standards will soon move against the “contains NO…” product which implies danger where no danger exists.


·         Alcohols – natural ethanol is a very useful chemical from nature’s arsenal and produced from yeast working on natural sugars to ferment natural alcohol. It is a solvent and astringent and a vital part of EDTs to help solubilise the perfume and also improve the dry down time.

·         Aliphatic – meaningless, this is a type of chemistry e.g. aromatic

·         Alkanolamines – agreed, there are better alternatives we could employ

·         Aluminum and alumina – perfectly safe and there is absolutely NO link with Alzheimer’s disease.

·         Amines – agreed if they are primary amines

·         Bromates – agreed, there are better alternatives

·         D.E.A – agreed if they contain primary amine as an impurity. If there is no Cocamide DEA then it gets very difficult to thicken detergent products. The problem is the free amine in combination with a formaldehyde source. Take away the source of formaldehyde as in formaldehyde donating preservatives and the problem is no longer a threat.

  • Dimethicone – made from silica through a very complex process and totally inert. There have been cases of breast implants filled with dimethicone that have leaked or burst and this cannot be healthy within the body cavity.

·         DMDM Hydantoin is a perfectly good preservative and provided it is used in an amine-free environment is very safe and extremely effective. The safety of DMDM Hydantoin has been assessed by the Cosmetic Ingredient Review (CIR) Expert Panel. The CIR Expert Panel evaluated the scientific data and concluded that DMDM Hydantoin was safe as a cosmetic ingredient in the present practices of use. In 2005, the CIR Expert Panel considered available new data on DMDM Hydantoin and reaffirmed the above conclusion. It is approved universally in Japan, USA and Europe.

·         EDTA – use phytic acid or sodium gluconate instead

·         Elastomer – not sure what this is as it has been a word taken out of context.

  • FD&C dyestuff and associated laked pigments. The letters stand for food, drug and cosmetic and are an extremely high specification of these colours which are approved and certificated on a batch by batch analysis by the FDA in the USA. Many of these colours are universally accepted in Japan, USA and Europe. There are restrictions according to the area of use. The toxicology on these colours is extremely well-known and they have been tested for a vast array of concerns and continue to be found safe. If you do not want to have colour, then do not use it.  The natural colours are not all approved for use in personal care products because they have not been tested for their safety.

·         Fluor – we wonder whether the scare was over fluorides – if so then every dental expert will curse you and all our teeth would rot!

  • Fragrances: synthetic fragrances do not contain animal urine or faeces. In the past the strongest base notes came from the sexual scent glands of materials like musk ox and civet which had a faecal odour. The best base notes are not at all pleasant and the best of these is aldehyde C11 which smells of vomit.  The statement that synthetic fragrances cause all manner of skin problems is a fallacy. The perfumery industry has a huge wealth of data on toxicity and safety studies and all of the individual raw materials have safety limits imposed on them which are set at a thousand times lower than the results calculated for increased safety. In reality it is the natural essential oils that contain most of the problems and IFRA have banned Melissa oil and Lemon Verbena as being to phototoxic for use on humans. There are 26 potential allergens that have to be declared on the pack if they exceed legal limits and more than half of these come from essential oils. Some essential oils are so dangerous that they should not be used during pregnancy (e.g. Clove stem oil, Pennyroyal or Rue). Some oils like Bergamot contain bergapten which is a toxic material that is a class of material called a psoralen and is phototoxic. Used in the right way this can be used in patients with vitiligo, but definitely to be avoided otherwise.

·         Fumarates – never seen these used in cosmetics anyway

·         Glycols and diglycols (such as propylene glycol) – Polyethylene Glycol and Propylene Glycol are safe

·         Hydrocarbons – this is a huge raft of chemicals and cannot be discussed in such general terms.

·         Imidazolidinyl urea is a formaldehyde donor and must not be used in the presence of amines. The safety of Imidazolidinyl Urea has been assessed by the Cosmetic Ingredient Review (CIR) Expert Panel. The CIR Expert Panel evaluated the scientific data and concluded that Imidazolidinyl Urea was safe for use in cosmetics and personal care products. In 2001, the CIR Expert Panel considered available new data on Imidazolidinyl Urea and reaffirmed the above conclusion. It is approved universally in Japan, USA and Europe.

·         Isopropyl Alcohol is not a great quality alcohol to use in skin care and I would always use ethanol in preference. We used to use it about 40 years ago in eye gels, I would not use it now!

·         Methacrylate. Totally innocuous and perfectly safe, some wonderful gels and thickeners with this. Lubragel is one such moisturizer I like!

·         Mineral Oil – Paraffinum Liquidum has been in the British Pharmacopoeia as a trusted drug since earliest editions. However, these oils come in different fractions, molecular weights and potential skin penetration. It is pure enough to be ingested. As a protector of the delicate skin of a baby against nappy rash it is excellent and Petroleum Jelly is a related moisturizer that has been proven again and again to be protective. It is comedogenic, but then so are many of the fixed oils or natural oils. Jojoba has good skin compatibility and is not strongly comedogenic.

·         Nitrates – I do not understand this one either, Potassium nitrate is a tooth desensitizer amongst other things and found in nature

·         Nitriles - agreed

·         Nitrosamine releasers - illegal

·         Nylon – totally inert but of petrochemical source. The fear is more to do with pollution of the sea.

·         PABA – organic sunscreen, universally accepted

·         Parabens – I LOVE parabens as they are found in nature and loved by dermatologists as they are safe with a very long history of not causing any problems.

  • Pentasiloxanes and higher silicones – a real concern starting to build in Canada and USA about a severe risk of environmental impact. Recently the Canadian environmental specialist said their fears were unfounded for the P% variant.

·         Petrochemicals – and where do they come from? – rotting bogs from millions of years ago – more natural than natural! Like all natural materials there are some parts like naphthenes and carcinogenic hydrocarbons that have to be separated out. They would never be a part of a cosmetic ingredient, but were used in products like creosote for wood preservation (and that has been banned as well). We live in a nanny state, many good things are banned which are of relatively low risk (I managed to stockpile some creosote for my fences).

·         Phthalates – not always pleasant, but some are used in synthetic fragrances quite safely. Not all phthalates are a problem.

·         POEs  - I like POEs as well because without them you cannot dissolve oils in aqueous systems very easily. They make detergents milder.

·         Poloxamer – totally inert, one of the mildest emulsifiers ever. It is a block copolymer but one of the good synthetics

·         Polyacrylamide – sounds awful but there are no reported problems using these materials which are totally inert.

·         Polyethylene Glycol (PEG): this is not a potentially carcinogenic petroleum ingredient that can alter and reduce the skin's natural moisture factor. The exact reverse is true, again listed in the British Pharmacopoeia as a powerful and innocuous humectant in the same water soluble moisturiser class as glycerin. This does not increase the appearance of aging, quite the opposite as it acts as a hydrating barrier that will attract moisture to the skin. Any idea that it leaves the skin more vulnerable to bacteria is ludicrous. It is never used in cleansers to dissolve oil and grease because it is water soluble and has no cleansing or detergent properties. I cannot think of any reason to use it in a caustic spray-on oven cleaner! It has been suggested that one alternative is Planteren™ (Plantaren?) which is nonsense because Plantaren is Decyl Glucoside or Lauryl Glucoside (class of detergent) and totally unrelated to propylene glycol, polyethylene glycol or glycerin.

·         Polyquaternium – you are in real trouble if you want a hair conditioner without this class of chemicals.

·         PPG’s – no scientific evidence for any adverse effects.

·         Propylene Glycol (PG) and Butylene Glycol. We have no idea why they have been described as petroleum plastics (implies they are polymers which they are not) nor do we understand how they can be described as "surfactants" (wetting agents) because they are both water soluble humectants that can act as solvents to extract the active principles from plants and botanicals. The source said that they easily penetrate the skin and can weaken protein and cellular structure but this is not true. They sit on the skin and attract water to the skin like all other glycols like glycerin. They may penetrate the stratum corneum and bind water there – so making the skin softer and more flexible. The source said “commonly used to make extracts from herbs” which is partly true because the glycol in combination with water has two effects – firstly to extract a broader spectrum of beneficial chemicals from the herb and second (if used at more that 15%) will remove the need to add preservative to the extract. In the real world the following is true The Food and Drug Administration (FDA) includes Propylene Glycol on its list of substances considered Generally Recognized As Safe (GRAS) for direct addition to food. Polypropylene Glycol is also permitted as an indirect food additive for use as a defoaming agent. The safety of Propylene Glycol, PPG-9, PPG-12, PPG-15, PPG-17, PPG-20, PPG-26, PPG-30 and PPG-34 has been assessed by the Cosmetic Ingredient Review (CIR) Expert Panel. The CIR Expert Panel evaluated the scientific data and concluded that Propylene Glycol and the Polypropylene Glycol polymers were safe for use in cosmetic products at concentrations up to 50%.

  • Sodium Lauryl Sulfate (SLS) & Sodium Laureth Sulfate (SLES): are NOT detergents and surfactants that pose serious health threats – this is totally inaccurate. Read the truth at It is probably true that it is used in car washes, garage floor cleaners and engine degreasers - and in 90% of personal-care products that foam. It is an excellent detergent that is rinsed off. The addition of Ccocamidopropyl Betaine reduces any irritant action by a factor of about 8. Ethoxylation makes the SLES less irritant. Transient contact with SLS and SLES will sting and cause lacrimation and require washing, but apart from transient stinging and perhaps some redness there would be no permanent damage.

·         Styrene – depends on the derivative, but in cosmetic ingredients there are no adverse effects. Not good for the environment.

  • Sulfate detergents e.g. Sodium Laureth Sulphate – they are very close to natural and the internet is full of ignorant and stupid reports of cancer and other silly comments which are totally unfounded.

·         Synthetic AHAs/BHAs – they are all synthetic anyway, despite the fact they are found in nature. At low levels they are perfectly safe, but we would be nervous of use as exfoliants at levels greater than about 4% unless in the hands of a professional.

·         Synthetic chelating agents – agreed, use phytic acid or sodium gluconate

·         Synthetic colours – this is more about ingested colours and certain hair dyes. The FD&C and D&C colours are perfectly safe. This is a marketing stance only.

·         T.E.A (triethanolamine) – agreed, mainly because of the risk of monoamines, but we use 99% in the cosmetic industry and this is totally innocuous. The old grade of 85% is no longer legal for use in cosmetics.

·         Triclosan: the source said “a synthetic "antibacterial" ingredient - with a chemical structure similar to Agent Orange!” This is total nonsense it is an antibacterial agent that kills the organisms that break down perspiration into odorous chemicals like mercaptens and other sulfur containing materials that smell unpleasant. The only thing that we would agree with is that the material is perhaps not very kind on the environment or watercourses and so we would choose not to use this material on that basis. It does take time to break down in the environment. Its wide-spread use in popular antibacterial cleansers, toothpastes and household products but we disagree with the overstated comment “may have nightmare implications for our future”.

·         Urea – the very best moisturizer ever. The body makes urea so it is totally natural. Loved by dermatologists.

·         Vinyl – this word is meaningless taken in isolation


If you have a concern then email me or get in touch with the CTPA to get the truth – don’t peddle garbage it makes you and your brand look ridiculous. There are materials that are not good for the skin – they are banned!