Not blu tack - if you're going to do that, you'll want to seal the holes with superglue or something of that nature.

How about velcro? - you can get velcro that's sticky (ie. you can stick it onto the cannisters) and then take the other piece of velcro, make a couple of holes in it for some string/thread (so you can hang it round your neck*) to and then you can stick container to you, remove it to use it and then stick it back again.

* I think that if you try and stick it to something round your wrist it'll get knocked off. Putting the other piece of velcro through a belt loop and sticking it on there might work though.