Irritants include poorly fitting dentures, licking the lips or drooling, mouth breathing resulting in a dry mouth, sun exposure, overclosure of the mouth, smoking, and minor
[dbpedia.org]
Lip balm protects the lips from the drying effects of the wind, dry air, salty foods, mouth breathing and habitual licking of the lips.
[livestrong.com]
breathing poor oral hygiene sun exposure smoking specific medical conditions such as diabetes, immune disorders, cancer of the blood, down-syndrome Symptoms of Minor Angular
[bluemcare.com]