Have a cellphone against your ear? You should consider putting it down

A pedestrian uses a mobile phone on Orchard Road in Singapore, on Monday, Feb. 29, 2016. Singapore's Infocomm Development Authority plans to auction additional mobile spectrum this year as it seeks to lure a new entrant to compete with the city's three existing providers. Photographer: Nicky Loh/Bloomberg

Put your cellphone down – and keep it away from your pillow, the California Department of Public Health is advising. 

Smartphone use continues to increase in the US, especially among children, and the health department said some people and health professionals have concerns about the radio frequency energy emitted from cellphones. The scientific community has not reached a consensus on the risks of cellphone use, but the health department said research suggests long-term, extensive use may affect health.