Tell your friend she's a wealth of erroneous information.

1. The nuclear reactors at Fukushima did not explode, that was the hydrogen gas the melting nuclear fuel gave off that exploded combined with the air. The radiation was primarily leaked to the sea. She would be better served worrying about her sushi

2. Japanese crops have been deemed as safe in testing.
3. Japanese cotton as noted above can actually come from other countries. It is not radioactive.
Have a nice day and hope your friend embraces reality vs tall tales and Internet fantasies