Thermal effects of emollients on facial skin in the cold.

Ointments are traditionally used in Finland for protection against facial frostbite. Recent epidemiological reports showed unexpectedly, however, that the use of ointments is a statistically considerable risk factor for frostbite of the face and ears. The effects of 4 different emollients on facial temperature were studied in 46 acute cold exposures. The voluntary test persons sat in a cold chamber after emollients were applied thickly on half of the face, while the other half acted as an untreated control. Thermistors and an infrared scanner were used to measure skin temperature of symmetrical areas of the face. The thermal sensations on the corresponding sites were also recorded. Test emollients more often had an objectively cooling than a warming effect on facial skin. However, white petrolatum often produced a subjectively warming skin sensation. "Protective" ointments may cause a false sensation of safety, leading to increased risk of frostbite due to neglect of other protective measures.