One of the more vexing questions during back-to-school-shopping season is whether to buy a cell phone. It’s a hard question to answer personally and a hard one for parents to agree on collectively.

(Courtesy of The Washington Post)

I’ve laid out my own case for holding off as long as possible on this particular necessity of modern life in a post about a new, to me terrifying, product called the Teddyfone.

We’ll get back to Teddyfone below. First, there’s new data about the danger, or lack of danger, for children who use cell phones.

A study published last week in the Journal of the National Cancer Institute reported that cell phone users ages 7-19 are at no greater risk of brain cancer than non-users.

Swiss researchers studied the cell usage of children in that age bracket who have brain tumors, comparing them to a control group. They found no statistical difference between the amount of time the cancer-stricken children spent on a cell phone.

Still, the researchers, as well as others who study the area, suggested in the same Journal issue that the area needs more consideration. This spring, the World Health Organization suggested that cell phones are “possibly carcinogenic.” And, as more and more children embrace mobile phones at younger and younger ages, it’s hard to know what the long-term effects could be.

Now back to Teddyfone. After I posted my case against this little phone, shaped like a teddy bear, available in pink or blue and easily used by toddlers, its U.S, distributor, Mitch Maurer, and I continued our conversation by e-mail.

Maurer wrote me that although his toddler twins play with the phone, it’s intended for children 4-years-old and older. Still several years too young for my taste, as I think the introduction of a phone at such a young age fuels our irrational fears about the safety of children and cripples the development of independence. Maurer and I respectfully agreed to disagree.

I’ve had my say in my earlier post. Here is more from his argument:

“Teddyfone has real potential to help families with children who may spend time alone during the day or between scheduled activities, children that walk through daily or live in areas that parents feel are not entirely safe and for children that may be at risk or have special needs.

“I also remember how important it was that I know my home phone number to call in case of an emergency when I was young. And I think of my [5-year-old] boy today who doesn’t need to know his home phone number — he needs to know his home phone, mom’s work, dad’s work, mom’s cell, and dad’s cell. Our children’s lives are much busier and more complex than mine was as a child.

“We also know that there may be instances where a child’s Teddyfone is more for the peace of mind and convenience of the parent or guardian than the safety of the child. Both parents work outside the home in more than 60 percent of families today, versus just over 30 percent in 1975. We see our children less and need to depend more on caregivers and after-school programs to watch over them.

“In some cases the phone may just be a convenient and fun way for a parent or grandparent to be able to reach out to their loved one when they are thinking about them.”

What do you think? What’s the right age for a child to have a cell phone? Why?