Interviews were obtained from 125 women with oral cavity cancer and 107 female controls to assess the role of mouthwash use as a risk factor for oral cancer in women. In addition to detailed information on mouthwash use throughout adult life, information was obtained regarding smoking, alcohol consumption, general oral hygiene practices, and occurrence of nonmalignant conditions of the oral cavity. Mouthwash use was not associated with increased oral cancer risk in terms of frequency, duration of use, dilution, or rinsing practices. Among mouthwash users, cases reported taking more mouthfuls of mouthwash at each use compared with controls. Again among mouthwash users, cases were significantly more likely than controls to give as a reason for using mouthwash “to disguise the smell of tobacco” and “to disguise the smell of alcohol,” whereas similar proportions of cases and controls reported using mouthwash to “disguise the smell of onions, garlic, etc.” and “to disguise breath odors due to mouth infections or dental problems.” These first two reasons for using mouthwash were strongly associated with smoking and drinking, respectively, and appear to be proxies for these exposures. Smoking, drinking, having 10 or more missing teeth, and religious background (non-Jewish versus Jewish) were significantly associated with oral cancer.
This research was supported by National Cancer Institute Program Project Grant CA32617 and Center Grant CA17613.