Very easy to get information on this topic. Armed with the information we can make our own choices.

This link discusses the lawsuit against the makers of Listerene, Johnson and Johnson, in 2011
http://www.pharmawatchdog.com/listerine-and-oral-cancer-is-there-a-connection/

"“There has been concern that the use of alcohol-containing mouthwash such as Listerine may increase the risk of developing oral cancer. As of 2010, 7 meta-analyses have found no connection between alcohol-containing mouthwashes and oral cancer, and 3 have found increased risk. In January 2009, Andrew Penman, chief executive of The Cancer Council New South Wales, called for further research on the matter. In a March 2009 brief, the American Dental Association said "the available evidence does not support a connection between oral cancer and alcohol-containing mouthrinse.”

This is from Wikipedia.