Years ago, when cellphones became more popular than beepers, scientists started to worry about the health ramifications. While some have deemed them safe, and pretty much forgotten about any concern, one group of Israeli researchers is saying that the radiation emitted from cellphones may cause oxidative stress, a process that's considered a main risk factor for cancer.

This time, instead of examining the brains of cellphone users, the researchers decided to look at the salivary glands, since they are just as close to a person's phone when they're talking on it. They tested the salivary content of 20 frequent cell phone users. These people were classified as using their phones to talk for a minimum of eight hours a month, however, the researchers said that some used their phones for as much as 30 to 40 hours a month.

They compared the participant's saliva with a group of deaf patients. These patients either didn't use cell phones, or only used them exclusively for texting and other non-verbal functions. They found that these participants had much lower levels of oxidative stress in their saliva compared to those who frequently used their cell phones.

"This suggests that there is considerable oxidative stress on the tissue and glands, which are close to the cell phone when in use," Dr. Yaniv Hamzany, of the Otolaryngology Head and Neck Surgery Department at the Rabin Medical Center in Tel Aviv, said in a statement.

Oxidative stress is important to the development of cancer, among other things, because it essentially disrupts the normal redox state of cells, damaging cells and their DNA through the production of peroxides and free radicals.

Although the number of participants was small, and the study didn't show a "cause and effect" relationship between cell phone use and cancer, the researchers said that it adds to building evidence that cell phone use may be harmful in the long-term.

Ninety-one percent of American adults own a cell phone. The average American spends about 144 minutes every 16 hours on their phone, and overall use of a cellphone is growing. Besides possibly affecting the development of cancer, there are many more short-term problems that can arise from cell phone use, including interfering with human relationships, increasing stress levels, chronic pain, and vision problems.

 

Source: Hamzany Y, Feinmesser R, Shpitzer T, et al. Is Human Saliva an Indicator of the Adverse Health Effects of Using Mobile Phones? Antioxidants and Redox Signaling. 2013.