Some studies have pointed to increasing evidence that alcohol based mouth rinses may be harmful when used repeatedly.
Ethanol in mouthwash is thought to allow cancer-causing substances to permeate the lining of the mouth more easily and cause harm.
Acetaldehyde, a toxic by-product of alcohol that may accumulate in the oral cavity when swished around the mouth, is also believed to be carcinogenic.
Table 1. Alcohol content of some commercially available mouthwashes (1)
Mouthwash Ethanol concentration (%)
Listerine Antiseptic 26
Listerine Cool Mint 22
Listerine Tartar Control 22
Listerine Citrus Fresh 22
Listerine Smooth Mint 21.6
Cepacol Mint 15
Savacol Original 11.5
Savacol Freshmint 9.5
Listerine Whitening 8
Neutrafluor 220 7
Neutrafluor 900 5
Natural Dentist 0
Oral B 0
Neutrafluor 220 Ethanol Free 0
Fluorocare 200 0
(1)The role of alcohol in oral carcinogenesis with particular reference to alcohol-containing mouthwashes
MJ McCullough, CS Farah, Melbourne Dental School, The University of Melbourne, Victoria.
School of Dentistry, The University of Queensland, Queensland, Australian Dental Journal 2008; 53: 302“305