First and for most - i just checked on the CDC and WHO site - there is no record of a 35% increase of birth deaths - and they would jump at that. I know, i have worked with them and they are great - and yes they are government. - they are some of the most dedicated folks i have ever worked with -.
Now you are talking (i.e.. tritium) this is a beta ommiter from a Hydrogen element (H2) being subjected to radiation. It is basically bad when you breath this into your lungs when within close proximity to being generated.
No worries about japan to us. no worries for your crop.
Basically if you are not goring into the reactor - no worries