Hi Robin,
Yes I've heard, thought and read about the Bisphenol A issue, but I am not worried about it with respect to the canned sardines. Someone in the forum at Mark's Daily Apple had a thread on the Bisphenol A issue in canned sardines before.
King Oscar maintains the cans are aluminum and lined with lacquer -- that raised more questions which the King Oscar rep answered to my satisfaction. I don't want to rehash it here but it's on the forum over at that web site.