No doubt about it, as regards the field from the mobile (10s of volts/metre at the head) being much higher than the millivolts/metre from a base station (BS) at 500yds. Even bang underneath the tower is OK, as most of the beam fires over your head (to get better reach to the horizon). Actually if your mobile operates power control corectly, it will throttle its transmitter back, when you are nearer the BS as it will only use the minimum power required to get through to it... longer battery life and all that, so the safest place to make the call is nearer the base station. Sadly, people don't think about it very hard, and see a big aerial, and instead of saying, "oh good, its well away from me on the ground", they panic.
regards M.