I've never had this problem before, try a mixture of cold water and dish soap use a spray bottle to spray it on, and wipe it off the lens right away. I wouldn't recommend any of these because it could irritate your eyes, or wreck the anti-for, but you could try a mild mixture of vinegar and water 1:5, or like a 1:20 ratio of bleach to water. Or you could just use lots and lots of warm water.