If alcohol drinking leads to oral cancer, then does this mean that using mouth wash also may cause cancer?

Unsure: While alcohol consumption is a significant risk factor (especially when mixed with tobacco smoke) for head and neck cancer, the debate about the effect of oral mouthwash continues. There is some belief that regular exposure may increase the risk of having abnormalities along the lining of the mouth.

Good question: Alcohol, by itself, is not nearly as strong a risk factor for oral cancer as alcohol and smoking. Inflammation of the oral cavity can increase the risk of oral cancer. Most alcohol based mouth rinses are formulated not to irritate and therefore have significantly less of a carcinogenic effect.

Perhaps: There have been suggestions that over a long period of time, alcohol containing mouthwash could have a carcinogenic effect. I do not know of any studies that confirm this, but funding for such a study might be difficult to get. The role of alcohol in producing oral cancer is probably it's ability to dissolve & extract chemicals from tobacco &carry them into the oral tissues where cancer starts.