Paraffin

Paraffin (paraffinum liquidum/mineral oil or soft paraffin/petrolatum fractions) is an inert, occlusive emollient used at high concentrations in moisturizers and ointments, with very low rates of irritant reactions in patch testing when adequately refined. Clinically, it is generally well-tolerated even in eczema and barrier-compromised skin, though rare irritation can occur from impurities or occlusion-related folliculitis rather than true chemical irritancy. Given its strong safety record but not absolute zero risk in real-world formulations, it fits an exceptionally gentle score rather than perfectly inert. Safety Notes: In consumer skincare, paraffin (typically as paraffinum liquidum/mineral oil and/or soft paraffin in ointment-type bases) appears at very low levels (~0.1–1%) as an emollient/texture modifier in lotions and creams, especially when paired with other oils and esters. It is also sold to the public in highly occlusive balms/ointments where paraffin (soft paraffin/petrolatum and/or liquid paraffin) can dominate the base at ~50–95%+, and pure cosmetic-grade paraffin oils/waxes and paraffin wax blocks for skin-conditioning/hand-foot ‘paraffin treatments’ reach 100% paraffin. Rinse-off cleansers typically use lower levels for slip and barrier feel, while leave-on ointments/balms and paraffin treatment products represent the upper end.