Okay, so it is no mystery that the Radiation from Japan has reached North America. The real question is, just how much has reached us?

I have seen several reports that say how much is here, and these reports compare it to xrays, and travel, etc. But I think that is an unfair comparison.

BC Local News states that measured levels of radiation reaching us are at 0.0000005 millisieverts.

They say a dental x-ray is about 0.015 millisieverts, or 30,000 times as much.

So on the surface it sounds like what we are getting is trivial, barely measurable… except for one thing. The radiation from Japan is constant, the radiation from a dental x-ray lasts no more than a second.

Lets assume that a dental x-ray lasts one second (I have no idea how long it really is, it could be a fraction of a second).

With that in mind, it would take 30,000 seconds for the exposure to radiation from Japan to equal that of a dental x-ray.

There are 86,400 seconds in a day (24hrs x 60 min x 60 seconds). That is nearly the equivalent of 3 dental x-rays. Would getting 3 dental x-rays a day be safe? Lets say the radiation exposure lasts 2 weeks. (I have no idea how long this exposure would actually last), but at 2 weeks, that is equivalent to getting about 42 dental x-rays. That cant be good can it?

I accidentally found this article: “Ten Dental X-rays ‘raise caner risk’.” If this study was true, and 10 dental x-rays can increase the cancer risk, then wouldn’t 42 of them in a 2 week period be 4 times as much of a risk?

Someone please tell me I am NOT onto something here… Have I made a big error in my calculations or understanding of something here? Drop a comment and let me know.


Note: Lets assume for a second, that a dental x-ray takes 1/10th of a second. That would still make the radiation from japan equivalent to roughly 4 x-rays over a 2 week period. Much less than my guesses above, but still more than they are comparing it too.

IMPORTANT UPDATE!!! – (March 28, 2011)


I received an email from an individual who manages a Nuclear Medicine Department. (I will source who he is if he replies to my email with permission). Essentially the radiation from Japan is on a “per-day” basis. So with that in mind, (assuming that my source is both legit, and correct) The actual excess radiation we are experiencing would be equal to one dental X-Ray approximately every 82 Years, not every 8 hours.

Assuming that this is all true, then I for one am convinced (that at the current levels) we are under no danger what so ever.

(Lets just hope the levels of radiation that find their way over here don’t increase at an significant level).