Isopropyl Myristate vs Paraffinum Liquidum: which is worse?

What is Isopropyl Myristate?

Isopropyl myristate is a synthetic ester of isopropyl alcohol and myristic acid (from nutmeg or palm kernel oil). It is a dry, silky-feeling emollient that also acts as a penetration enhancer.

What is Paraffinum Liquidum?

Paraffinum liquidum is the INCI name for mineral oil — a highly refined, colorless, odorless petroleum-derived hydrocarbon liquid. It has been a staple cosmetic emollient for over a century.

Documented risks

Isopropyl Myristate: Isopropyl myristate is CIR-safe at cosmetic use concentrations. Like IPP, it has a notable comedogenicity rating (3–4/5) and may contribute to clogged pores in acne-prone users. Its penetration-enhancing properties mean that whatever active ingredients it accompanies are delivered more deeply into the skin — this is generally desirable but should be noted. No carcinogenic or endocrine-disrupting effects are documented.

Paraffinum Liquidum: Cosmetic-grade paraffinum liquidum (highly refined mineral oil) is considered safe by the CIR and FDA. The EU restricts use based on refining grade, specifically prohibiting inadequately refined mineral oils that may contain carcinogenic PAH compounds. Highly refined grades (used in cosmetics globally) have no identified carcinogenic risk. Mineral oil does not penetrate intact skin and is not absorbed systemically. It is non-comedogenic at low concentrations; higher concentrations may contribute to congestion in acne-prone skin. Inhalation of mineral oil mist in occupational settings is a separate concern not applicable to cosmetic topical use.