I use my mobile phone a lot while I'm out and about on business travel. Do you think this is OK healthwise?

Well, so far there is no definite evidence mobiles cause brain tumours or other illnesses. However, in ten years' time there might be scientific proof of such ill-effects. At the moment, the best plan seems to be to keep mobile phone calls reasonably short.

Also, commonsense suggests it's a good idea to avoid using the same ear all the time.