Many have discussed whether or not radiation from cell phones causes cancer. Author Douglas Fields writes about the fact that some people are fearful of radiation from their cell phones, but that fear indicates the lack of understanding in regard to dosage:

There is a vast difference, for example, between a microwave oven and a cell phone. Just try cooking a burger with your phone. The word “radiation” strikes fear in the heart of the average person. But radiation is a normal part of our environment, cast down on us together with the warming rays of the sun. Radiation emanates from the smoke detectors in our homes and from dishes that use uranium salts in their ceramic pigments. But all are perfectly safe because the radiation levels are low.

Still, some are skeptical and they recommend not allowing children to use cell phones except in emergencies, and to avoid carrying cell phones on the body. Fields points out:

The debate and research go on. This seems strange given the abundance of known agents and activities that do cause cancer but fail to strike the same fear in the hearts of most people. Alcohol, tobacco, sunburn, toxic organic chemicals in industrial and home products are all real but accepted risk. Yet the cell phone and invisible radiation from power lines scare many. Looked at objectively, the reason is simply fear of the unknown. Everyone understands alcohol and sunburn; few understand radiation, and so they fear it.

Possible Preaching Angles:

Christians wonder, how serious is friendship with their world? How much sin will hurt me? How can I be in the world but not of the world? Low doses of sin can be overlooked, but they can combine for a very serious effect in our spiritual lives.