Hydrogen Peroxide, one of the main ingredients in tooth whitening product found to have no negative health effects and is safe to use-says an article written by Dr. Ian Monroe, entitled, "Use of Hydrogen Peroxide-Based Tooth Whitening Products and it Relationship to Oral Cancer"
The article was published in Journal of Esthetic and Restorative Dentistry after an exhaustive review including unpublished clinical studies of over 4000 human subjects. The article highlights the point that common tooth whitening products, which have been used by millions of people, do not increase the risk of oral cancer when used as directed.
Clinical and laboratory data on tooth whitening products show no evidence for the development of oral cancer or of other effects that could be associated with increased oral cancer risk. Exposures to hydrogen peroxide, generally the effective ingredient in tooth whiteners, are too low and of too short of a duration (30-60 minutes) to cause any oral tissue changes that could enhance risks for oral cancer development. Concentrations of hydrogen peroxide rapidly decline to near undetectable levels usually within 15 to 60 minutes.
Given the likely use of tooth whitening products by smokers, the review also sought to examine any possibility of increased oral cancer development due to combined exposure (i.e., hydrogen peroxide and carcinogenic agents that are present in cigarette smoke). A possible combined-effect, as seen in the increased likelihood of lung cancer development in smokers also exposed to asbestos, was found to be groundless with regards to bleaching and smoking and further illustrates the relative safety of tooth whitening products.