I have taken my Minox with 400 film in it to and fro through the x-ray machines in Europe a couple of times, and no fog occured. But I recently heard that new, unsafe machines are currently being installed in a couple of places. As far as I remember, however, this did not refer to hand luggage but to checked baggage. I heard that when they see a dark spot on the screen when x-raying checked baggage, they just send it back through the machine and use higher x-ray intensity so they can still see what it is. Then even the lead bags won't help.(posted 9004 days ago)The suggetion with the canisters is probably a good one. I think there is no right to manual inspection, so all you can do is ask real nice. I have had guys at the gate who even insisted on pulling a little at each film. The very least is that they will want to open each container to see the actual cartridges. (Or they will say "Too much work! SEnd it through the x-ray machine!") So use transparent containers, or- even better - transparent plastic bags. It might also be a good idea to go to the gate when it's not so crowded, or you might have a very pressed business traveller behind you who complains about missing his plane because of your extra wishes.
How about using bulk film spooled into plastic cartridges? You should be able to carry that on your body and walk through the magnetic gate without any alarm ringing.