Without the will to offend you, I have to say that you answer is rather silly. Rather than say that oranges can give you cancer, ask yourself why there is completely lack of information about sar value. They don't want to make people aware of the risk. Serious and independent studies (I mean without the financial support of the big companies) are saying just the contrary of what you are saying.
Further n900 is a tablet, so you have to keep near the eyes for a long time. wifi too is risky. But of course they are not giving the numbers.