Is phenoxyethanol harmful to the skin?

What is phenoxyethanol?
Phenoxyethanol is a glycol ether formed by combining phenolic groups with ethanol, and it appears as an oil or mucilage in its liquid state. It is a common preservative in cosmetics, and can be found in everything from face creams to lotions.
Phenoxyethanol achieves its preservative effect not through antioxidant but through its anti-microbial activity, which inhibits and even removes large doses of gram-positive and negative microorganisms. It also has a significant inhibitory effect on a variety of common bacteria such as E. coli and Staphylococcus aureus.
Is phenoxyethanol harmful to the skin?
Phenoxyethanol can be lethal when ingested in large doses. However, topical application of phenoxyethanol at concentrations less than 1.0% is still within the safe range.
We have previously discussed whether ethanol is metabolized to acetaldehyde in large quantities on the skin and whether it is absorbed in large quantities by the skin. Both of these are also quite important for phenoxyethanol. For skin with an intact barrier, phenoxyethanol is one of the fastest degrading glycol ethers. If the metabolic pathway of phenoxyethanol is similar to that of ethanol, the next step is the formation of unstable acetaldehyde, followed by phenoxyacetic acid and otherwise free radicals.
Don't worry yet! When we discussed retinol earlier, we also mentioned the enzyme system associated with the metabolism of phenoxyethanol, and that these conversion processes occur under the stratum corneum. So we need to know how much phenoxyethanol is actually absorbed transdermally. In one study that tested the absorption of a water-based sealant containing phenoxyethanol and other anti-microbial ingredients, pig skin (which has the closest permeability to humans) would absorb 2% phenoxyethanol, which also increased to only 1.4% after 6 hours, and 11.3% after 28 hours.
These studies suggest that the absorption and conversion of phenoxyethanol at concentrations less than 1% is not high enough to generate harmful doses of metabolites. Similar results have also been obtained in studies using newborn infants less than 27 weeks. The study stated, "Aqueous phenoxyethanol does not cause significant skin damage compared to ethanol-based preservatives. Phenoxyethanol does get absorbed into the skin of newborn infants, but does not form the oxidation product phenoxyacetic acid in significant amounts." This result also indicates that phenoxyethanol has the highest rate of metabolism in the skin and does not cause significant damage. If babies can handle it, what are you afraid of?
Who is better, phenoxyethanol or alcohol?
Although phenoxyethanol is metabolized faster than ethanol, the maximum restricted concentration for topical application is much lower at 1%, so it is not a good comparison. Since the stratum corneum prevents most of the molecules from being absorbed, the free radicals generated by these two are much less than those generated by their own oxidation reactions every day! Moreover, because phenoxyethanol contains phenolic groups in the form of oil, it evaporates and dries more slowly.
Summary
Phenoxyethanol is a common preservative used in cosmetics. It is safe and effective, and is second only to parabens in terms of usage. Although I think parabens are also safe, if you are looking for products without parabens, phenoxyethanol is a good choice!