Ingredient
4-HYDROXYBENZOIC ACID
Name / description
4-Hydroxybenzoic Acid
Function(s) of this ingredient in cosmetic products
FRAGRANCE
Enhances the smell of a product and / or perfumes the skin
PRESERVATIVE
Protects cosmetic products from microbial spoilage
Origin
synthetic
Occurrence in cosmetics
In skin care and cleansing products such as emulsions, creams, shampoos as well as in styling products and many other cosmetic products
Background information on use in cosmetics
Preservatives protect cosmetic products against microbial spoilage and hence make a major contribution to consumer health. Preservatives are particularly required in cosmetic formulations containing water, because microorganisms can colonise and reproduce in an aqueous (water-containing) environment. Cosmetics often contain more than one preservative substances and these preservative systems act simultaneously against different bacteria, yeasts or moulds. Each of these substances has been comprehensively tested and assessed for safety (individually and in combination). Manufacturers always use only the lowest possible effective concentration in a product so that an optimum shelf life and safe application are ensured. Parabens are salts and esters of para-hydroxybenzoic acid. Like the related benzoic acid, they have an antimicrobial and fungicide effect. For that reason some esters have been added since more than 80 years as preservatives to cosmetics. The following are allowed in cosmetic products: para-hydroxybenzoic acid (paraben), methyl paraben, ethyl paraben, propyl paraben, butyl paraben, as well as some of their sodium, potassium and calcium salts. In nature parabens occur in many plants such as cucumbers, carrots, onions, cherries, blueberries or strawberries. Fragrances or mixtures of fragrances are often referred to in the cosmetics area as "perfuming agents" or "perfume oils" or "parfum oils". On the cosmetic products they are declared with the INCI name "PARFUM". These are undiluted individual substances or their mixtures which originate from natural raw materials or can be produced (semi-) synthetically. They are starting materials for the production of perfume, eau de parfum, eau de toilette, eau de cologne and other perfumed cosmetic products. The average content of fragrances amounts in perfume to 15-30 %, in eau de parfum to 10-14 %, in eau de toilette to 6-9 %, in eau de cologne to 3-5 % as well as in skin creams, shampoos, hair and deodorant sprays to approximately 0.2-1 % and approximately 1-3 in deodorant sticks. The perfume oils include essential oils, resinoids and absolutes. The sources are, amongst others, flowers, leaves and stems, fruits and fruit peels or roots of plants; woods, grasses or herbs, needles, resins and balsams. Moreover, only compounds isolated from natural products such as aldehydes, ketones, esters, alcohols etc. are used (geraniol, citronellal, citral, eugenol, menthol) as well as semi-synthetic (citronellol, geranyl acetate, jonone) and synthetic scents (eg phenylethyl alcohol and linalool) are used. Scents of animal origin such as musk and ambra are only rarely used.
Information on safe use
From a scientific point of view, parabens are the currently best investigated and safest preservatives on the market. BfR (German Federal Institute for Risk Assessment) classifies them as safe. In 2010 the SCCS reviewed the concentrations of the individual parabens in cosmetic products and re-confirmed in May 2013 that parabens can be classified as safe in the concentration in which they are used in cosmetic products. Current literature proves that parabens are in allergological terms amongst the preservatives with a particularly low allergenic potential. There are reports about allergies but if one relates them to the frequency of use (many products on the market are preserved with parabens), parabens can be designated as allergologically inconspicuous. In accordance with the EC Cosmetics Regulation (Regulation (EC) No. 1223/2009), which applies to the entire EU market, preservatives means substances which are exclusively or mainly intended to inhibit the development of microorganisms in the cosmetic product. Annex V of the Regulation defines the substances which may be used as preservatives in cosmetic products. In this so-called positive list of preservatives, maximum concentrations are defined for the use of these substances in cosmetic products as well as the permissible uses. Preservatives are examined in respect of their toxicological safety prior to their approval in Annex V and undergo extensive tests. Manufacturers must prove the health safety in extensive scientific studies.
Links to scientific assessments
Opinion of the SCCS (2013) on the safety of propyl and butyl parabens
Position paper of BfR (2011) on the use of parabens in cosmetic products (in German)
Opinion of the SCCS (2010) on the safety of parabens as preservatives in cosmetics
Why are we talking about it?
Parabens are suspected of being endocrine disruptors. The facts: The safety of use of the parabens authorised in cosmetics, which are preservatives that are very well tolerated in cosmetic products, has been widely evaluated by numerous expert committees (European, American, Dutch, etc.) (2, 3 and 4). Parabens were found to have a low estrogenic activity in vitro (refers to studies or experiments carried out in non-animal test systems auch as cell cultures, tissue cultures or bacteria) which is significantly lower (more than 1000 times) than that of the physiological human reference hormone (estradiol). The in vivo results (studies or experiments carried out on intact mammalian organisms) are inconclusive but do not support the suspicion of an endocrine disrupting activity. Moreover, percutaneous penetration data suggest that parabens with shorter side-chains are less bioavailable and have a weaker endocrine activity. The only parabens used in cosmetics have side-chains containing 1 to 4 carbon atoms: methylparaben < ethylparaben < propylparaben < butylparaben). This is why the safety in use of parabens is analysed substance by substance. Butylparaben, methylparaben and propylparaben are among the 28 substances suspected of being endocrine disruptors, which are being re-evaluated by European experts to analyse any new data on their potential endocrine activity. Propylparaben has already been assessed and considered safe for use at the low concentrations at which it is used in cosmetics. The assessment is difficult because the in vivo results are inconclusive (1). Further studies are underway at European level to clarify this question definitively. It should be mentioned, that sufficiently sensitive in vitro assays have identified endocrine activity of e. g. soybean ingredients (isoflavones), whereas scientific and regulatory experts have not expressed safety concerns with regard to ingestion of soybean based food. The safety of parabens has been assessed by applying the most drastic scenario ("worst case scenario", i.e. the highest exposure and skin absorption values are considered alongside the lowest no-effect dose value). The experts (European and American) consider parabens to be safe for use in cosmetic products at the authorised concentrations. Key points to take away: Like all preservatives, parabens are highly regulated by European regulation. The parabens currently authorised in cosmetic products are considered safe for use by several expert committees. Additional studies are underway at European level to definitively rule on their potential endocrine disrupting character. Sources: (1) In vitro data allow to identify a mechanism of action. To find out whether this mechanism has an effect on a living organism, in vivo studies are carried out. (2) Opinions of the European Scientific Committee on Consumer Safety a. SCCP/0873/05: https://ec.europa.eu/health/ph_risk/committees/04_sccp/docs/sccp_o_019.pdf b. Extended Opinion on Parabens, underarm cosmetics, and breast cancer, SCCP/0874/05: http://www.alegesanatos.ro/dbimg/files/Parabens.pdf c. SCCP/1017/06: https://ec.europa.eu/health/ph_risk/committees/04_sccp/docs/sccp_o_074.pdf d. SCCP/1183/08: https://ec.europa.eu/health/archive/ph_risk/committees/04_sccp/docs/sccp_o_138.pdf e. SCCS/1348/10: https://ec.europa.eu/health/sites/health/files/scientific_committees/consumer_safety/docs/sccs_o_041.pdf f. "Clarification on Opinion SCCS/1348/10 in the light of the Danish clause of safeguard banning the use of parabens in cosmetic products intended for children under three years of age", SCCS/1446/11: https://ec.europa.eu/health/sites/health/files/scientific_committees/consumer_safety/docs/sccs_o_069.pdf g. SCCS/1514/13: https://ec.europa.eu/health/scientific_committees/consumer_safety/docs/sccs_o_132.pdf (3) Cosmetic Ingredient Review (CIR): Amended Safety Assessment of Parabens as Used in Cosmetics (2020): https://pubmed.ncbi.nlm.nih.gov/32723119/ (4) National Institute for Public Health and the Environment (RIVM report 2017-0028): Exposure to and toxicity of methyl-, ethyl- and propyl paraben (https://www.rivm.nl/bibliotheek/rapporten/2017-0028.html)
Belongs to the following substance groups
Regulating cosmetics
Cosmetics Ingredients are subject to regulation. Please note, different regulations may apply to cosmetic ingredients outside the EU.