With proper care, you can shoot on the beach with no issues - I even change lenses at the beach sometimes (but more often, I take a couple of bodies with the lenses I'm planning on using on them so I don't have to do so). The biggest issues you have to concern yourself with are sand and salt spray. Wipe your camera down with a slighty damp lint free cloth before you put it away, clean your len's exterior in the same manner. If you did get sand on the camera, blow the sand off first before wiping it down and that will help to preven the sand from scratching the exterior.