I’ve always used earplugs and have never had a problem. I wouldn’t even think about paddling in our toxic and shit infested rivers without them. Consider all the crap that runs off the land and into your ears, nose and mouth during the melt down. I always take a good belt of strong whiskey after every run. By the time you’ve done 15 or 20 you’re well disinfected. A great alternative to ear plugs is a waterproof MP3 player with waterproof earbuds made by Oregon scientific.