Link between mouthwash and oral cancer in dispute

A battle has broken out between dental health experts over claims by an academic researcher that the alcohol present in mouthwash products increases the risk of oral of cancer.

The warning comes in an article published in the Australian Dental Journal by Associate Professor of Oral Medicine, Dr. Michael McCullough and says there is sufficient evidence that mouthwashes containing alcohol increase the risk of oral cancer.

Dr. McCullough carried out a review of research into how alcohol is involved in the development of oral cancer and looked at literature which has linked alcohol-containing mouthwashes and oral cancer and as a result he has called for mouthwashes containing alcohol to be reclassified as 'prescription only' and removed from supermarket shelves.

But not everyone agrees and some experts say such products are more likely to prevent the disease.

The head of the University of Queensland's School of Dentistry, Professor Laurence Walsh, says there are a number of reasons why some mouth rinses would actually reduce the chance of the cancer because their action impairs the production of molecules like acetaldehyde that have cancer-causing effects.

Professor Walsh says there is evidence which has international support that mouth rinses containing alcohol used to reduce bacteria which produce acetaldehyde are not linked to cancer.

But according to Dr. McCullough acetaldehyde, a toxic by-product of alcohol suspected to be carcinogenic, may accumulate in the oral cavity when mouthwash is used and he says there is no evidence showing the molecule could either suppress or prevent cancer.

Some cancer experts suggest there may be a potential risk in using alcohol mouth washes and caution against the daily use of a powerful alcoholic-based mouthwash especially by smokers to mask the smell of cigarette smoke - they say more research is needed into such products.

They advise anyone finding anything unusual in their mouths, such as unexplained lesions, to see their dentist or doctor.

The Australian Dental Association, which endorses the product Listerine, has called the review "very interesting" but says there is no definite proof that alcohol contained in mouthwash products can cause cancer.

The Dental Association says a link between heavy drinking and cancer has been established and therefore there is a possible link with long term multiple uses of alcohol contained in mouthwashes but more research is needed before this can be definitely said to exist.

A wide body of research has linked smoking and alcohol consumption to the development of oral cancer - in Australia each year over 800 new cases are reported.