Phenoxyethanol

Phenoxyethanol is the preservative that replaced the preservatives people stopped wanting. As formaldehyde donors and then parabens fell out of commercial favour, it absorbed much of the work. It now appears in creams, foundations, cleansers and wipes at almost every price.

It is a colourless oily liquid with a faint characteristic odour^[1] — the perfumery trade has long sold it under the name rose ether — and the job it does is unglamorous. A water-based cosmetic is warm and nutritious, and a jar opened daily is inoculated daily. Something has to stop what grows.

Chemically it is 2-phenoxyethanol: a benzene ring joined through an oxygen atom to a short two-carbon alcohol.^[2] That structure explains the behaviour. The aromatic ring makes the molecule oil-loving enough to cross a microbial membrane; the alcohol end keeps it soluble enough in water to reach the water phase, where spoilage organisms actually live.

It is made industrially by reacting phenol with ethylene oxide. Trade literature states frequently that it also occurs naturally in green tea, and the claim is repeated by manufacturers and retailers alike.^[3] No primary analytical study supporting it surfaced in the sources consulted here, and it is better treated as an industry commonplace than as an established fact. The material in a cosmetic is synthetic in any case.

Trade literature also places its introduction as a cosmetic preservative in the middle of the twentieth century. No primary source consulted here fixes a first year for that, so this entry records none rather than repeat a date it cannot stand behind.

The Scientific Committee on Consumer Safety describes phenoxyethanol as a broad-spectrum preservative with excellent activity against a wide range of Gram-negative and Gram-positive bacteria, yeasts and moulds, used in cosmetic formulations at a maximum concentration of one per cent.^[4] It is rarely the only preservative in a product even so. One study reviewed in the same opinion put the minimum inhibitory concentration against Pseudomonas aeruginosa, the organism a water-based cosmetic has most to fear, at 0.4 per cent^[4] — which leaves little headroom beneath a ceiling of one.

The opinion records two further uses. It is a solvent, and its solvency is the reason given there for its appearing in so many blends and mixtures with other preservatives; and it is a fragrance ingredient in its own right, used in many fragrance mixtures.^[4] Because it is not an acid, its activity does not depend on the formulation staying acidic in the way benzoic or sorbic acid's does, and that indifference to pH is a large part of its appeal to a formulator.

Phenoxyethanol is listed at point 29 of Annex V to Regulation (EC) No 1223/2009, the European Union's Cosmetics Regulation, which sets out the preservatives allowed in cosmetic products and limits this one to one per cent of a ready-to-use product.^[5]

That ceiling has been tested. In 2012 the French agency ANSM submitted a risk assessment to the European Commission arguing that the limit should be cut to 0.4 per cent in products for children under three, and that phenoxyethanol should not be used at all in products for the nappy area. The Scientific Committee on Consumer Safety examined the case and concluded, in an opinion adopted on 6 October 2016, that one per cent remains safe for consumers, children included.^[6]

The Commission did not amend the limit, and France acted alone. By a decision of 13 March 2019 the Director-General of ANSM, invoking the safeguard clause at Article 27 of the Regulation, required leave-on cosmetics containing phenoxyethanol on the French market — deodorants, hairdressing products and make-up excepted, and whatever their concentration — to state on the label, within nine months, that they may not be used on the bottoms of children aged three years or less. The Commission wrote in November 2019 to say that a measure of general application to a category of products containing a given substance was not an exercise of the safeguard clause at all; ANSM replied that it intended to maintain the decision pending the Commission's own determination.^[7] The industry federation took the decision to the Conseil d'État, which referred the question to Luxembourg, and on 15 September 2022 the Second Chamber of the Court of Justice ruled that Article 27(1) does not allow the competent authority of a Member State to adopt general provisional measures applying to a category of products containing the same substance.^[7] The European Union limit is still one per cent.

In the United States the Food and Drug Administration warned on 23 May 2008 against Mommy's Bliss Nipple Cream, marketed by MOM Enterprises of San Rafael, California, whose labelling told nursing mothers there was no need to remove the cream before feeding. The agency named two ingredients. Chlorphenesin relaxes skeletal muscle and can depress the central nervous system and cause respiratory depression in infants; phenoxyethanol, the advisory said, can also depress the central nervous system and may cause vomiting and diarrhoea leading to dehydration.^[8] That was an advisory about one product an infant would swallow directly and repeatedly, and it is not a finding about the same preservative at one per cent in a face cream. But it named the ingredient's own effects, not merely the route by which they would be reached.