Minimun daily intake for magnesium is about 400mg and your body will use more under stress. I would at least double your dose or consider adding an oral mag supplement as well. Do you have "natural CALM" over there? It is an easy, well absorbed form if you are looking for one....
I don't know what's going on with the radiation. If they are talking about non-ionizing radiation, it is easy to check your surroundings with a Trifield meter for EMF's (electromagnetic frequencies). Safe readings should be below 3 milligauss. I find the worst exposures are from radio alarm clocks on people's bedsides and the terminal box on your computer cord....here is a good video..