I've been a ham operator for a long time as well, although not quite as long as my fellow ham AZ.
I'm also not that terribly concerned about the RF exposure, although I'm not exactly as cavalier about it as he appears to be.
There are many factors involved with this including the operating frequency (ham equipment can be anywhere from around 1 MHz to 1300 MHz, phones range from 700-2100 MHz), transmitter output, mode of transmission (digital vs. analog), and so on. Some frequencies are more readily absorbed by body tissue.
One reason I don't keep the phone in a pants pocket and always use a belt holster is to keep the RF away from the reproductive bits, although it also has to do with convenience and protecting the phone from other stuff in the pockets. The way that RF field density works, it falls off logarithmically with distance so keeping it just a couple of inches away from the body makes a significant difference.
And all that said, with the phone in standby it's not constantly transmitting anyway, just an occasional ping to the tower and only a constant signal if a call comes in. It's while you're in a call that it is radiating the most and then you're probably holding it in your hand (against your head). During the call you can hold the lower part of the phone away from your face and just have the speaker against your ear, the antenna is usually at the bottom rear of the phone and this will keep it further away.
But the bottom line with our phones is that the transmitter power they run is relatively low, the maximum output of a phone is about 1/2 watt. One thing you can be aware of is the signal level of the tower you are connected to, the way the system works is that the stronger the tower the less power the phone will use. So if you're near a strong tower with full bars your phone will only be putting out a small fraction of its maximum, probably just a few milliwatts. This is better for you and also for the phone as it will use less battery.
