Mods- hope this link is OK. This is a blog that updates Tokyo radiation levels. This is the link to Sept this year:Tokyo radiation levels – daily updates – September | chottomatte.net

Radiation in Tokyo is sitting at around double normal background radiation at the moment. But to put that in perspective- average level is 0.2 micro sieverts per hour in a city so Tokyo is still showing a lower level than most cities on the planet.

I guess all I can suggest is to do some reading on radiation levels and see what you feel comfortable with. I would not worry about the levels being sent out of Tokyo at the moment. You'd have more exposure to radiation if you visited New York.