Studies on people have left more questions than answers, and laboratory experiments have failed to pin down a plausible mechanism whereby weak magnetic fields could trigger the disease.
Since then, most European nations as well as Japan and Canada have adopted this so-called EMV international credit card standard and abandoned magnetic stripe credit cards for chip-and-pin cards in the process.
Security concerns have led many places in Europe to accept only chip-and-pin credit cards, which causes trouble for travellers with magnetic-stripe cards.