According to the ASPCA lucky bamboo is toxic to cats if they ingest it. As far as, I know lucky bamboo does not release a toxin into water. If the cat only drinks the water, she should be ok.

so ive done some quick research and discovered that lucky bamboo is not good for dogs or cats….

i have two baby “stalks” about 4 inches high and i have the arrangement in pebbles and water….the water comes up about half an inch over the pebbles…and i have noticed that by the end of the day the water will be the pebble level…..so either the plants are SUPER thirsty,….or my cat has been drinking the water (im pretty sure its my cat)…this has been going on for about a week or a lil more…. my question to you is,….if my cat continues drinking this water…… will she get sick….if SHE DOES NOT EAT THE PLANT,.but drinks the water….is it as toxic as if she were to actually eat the plant?…..
thank you for your time,…and your response would be greatly appreciated,
~elda

According to the ASPCA Dracaena sanderiana (lucky bamboo or ribbon plant) can be harmful to cats and dogs if they ingest it.
Cats will have dilated pupils, abdominal pain, increased heart-rate and drolling if they ingest lucky bamboo. Both cats and dogs will show signs of depression, inappetance, drooling, vomiting, incoordination and weakness if they ingest lucky bamboo.

My suggestion would be to place lucky bamboo where cats and dogs could not get to it.