Effect of areca nut on salivary copper concentration in chronic chewers

The chewing of areca nut is associated with the development of oral submucous fibrosis (OSF), a condition predominantly encountered in Asians indulging in the habit. The pathogenesis of this condition is however, unclear, though several mechanisms have been proposed. Copper has previously been implicated as a possible aetiological factor. In this study, total copper concentration was measured via atomic absorption spectrophotometry in whole mouth saliva of 15 volunteers who were regular chewers, before and after their habitual chew. An aliquot of the latter was also analysed for copper. Six non-chewing volunteers acted as controls. Salivary copper concentrations were corrected for protein content. Over 50% of the subjects had basal salivary copper concentration higher than the range seen in normal controls. All but two subjects demonstrated an increase in the salivary [Cu] following their habitual chew. Marked changes were seen in those with low basal salivary concentrations. These data indicate that soluble copper found in areca nut is released into the oral environment of habitual chewers. Its buccal absorption may contribute to the oral fibrosis in Asians who regularly chew this nut.