A review of studies by Physicians for Safe Technology
The Environmental Health Trust has a wealth of articles, videos, and links about cell phone use.
For those who want to dive in and learn more, see Dr Joel Moskowitz's website:
Read your cell phone manual
10 Tips to Reduce Cell Phone Radiation
PSA's and Videos, including for children and teens: https://ehtrust.org/resources-to-share/public-service-announcements-cell-phone-radiation/
Use a landline whenever possible;
there is no radiation. There are many models available now online and at reasonable prices. There are many styles and some have speakerphone options for hands free calling. Use a longer cord either from the wall to the phone or from the phone to the headset if needed or desired.
Copper landlines are best because they remain functional in a power outage.
Cordless phones have a great deal of wireless radiation, even when not in use. An old fashioned, corded landline or one with a speakerphone is safest.