It doesn't appear on the lengthy list I found here:

http://www.geocities.com/stuartplaid/toxic.html

So it may be safe. I have a little lavendar plant by the kitchen door, and I wondered if Miss Hoppy (my bunny) would eat some of it. She ate a whole row of lavender seedlings once, but they were sunning on "her" windowsill, so it may have had more to do with that than with their taste!