Smudgy pencils

A question for you practising artists out there: Do you use pencils in your sketchbooks? The sketchbooks you carry around with you, I mean, not the ones you leave at home. And if so, how do you keep the pencilled work from smudging to hell and back? (I suspect the answer will turn out to be Spray it with fixative when you get home, but maybe there’ll be another possibility that poses less danger to my lungs.)

Maybe I should join one of the artist’s communities on LJ and ask there.

I’ve been restricting myself to pigment marker and occasional watercolor pencil in my travelling sketchbooks, but there are times when ordinary pencil work would be easiest, and I’d like to be able to go back to it without having to worry about the work turning into a cloud of graphite within a few weeks.

(I’ve got the germ of an idea for a web comic strip, and I’m going to try to get it to sprout over the next couple of weeks.)