A new study implicates cell phones in male infertility. It’s the most recent of the many studies that link – or fail to link – cell phone use to health issues.

A team led by Ashok Agarwal at the Cleveland Clinic Lerner College of Medicine at Case Western Reserve University in Ohio conducted the research, reported in Canada’s Globe & Mail newspaper, the BBC and other news sources in October. Researchers divided 364 men who were undergoing evaluation for infertility into groups according to their cell phone usage. They ranged from no use, less than two hours a day, two to four hours a day and more than four hours a day.

The study showed that their sperm declined steadily in number, quality and ability to swim as mobile phone usage increased. Where men used their mobiles for more than four hours a day, researchers found a 30 percent drop in sperm motility or movement and viability when compared with men who did not use a mobile phone.

The researchers noted that the study could indicate that the electromagnetic fields (EMFs) generated by mobile phone handsets are interfering with sperm production, and recommended further investigation into this and other aspects of the study.

EMFs have been implicated in other studies into cell phone usage and health. The July issue of The Ergonomics Report™, a publication for professionals in ergonomics-related disciplines,includes research findings published in The Lancet in June 1998 that maintain cell phone use can significantly increase blood pressure. Dr. Stephan Braune of the University Neurology Clinic in Freiburg, Germany, said EMFs emitted by the telephones could have adverse effects on people suffering from high blood pressure or hypertension, an important risk factor for heart disease and stroke. And Swedish study published in 2002 claimed to have found a link between analogue cell phones and brain tumors. Some users reported fatigue, headaches and burning skin from using their device.

As The Ergonomics Report™ article points out, there is no consensus on whether the devices can cause health problems: some experts scoff at the idea.

The results of the sperm study have already been challenged. Allan Pacey, senior lecturer in andrology at Sheffield University in Britain, described it in an interview with the BBC as “a good quality study,” but thinks it fails to tackle the issue: “If you're using your phone for four hours a day, presumably it is out of your pocket for longer. That raises a big question: how is it that testicular damage is supposed to occur?"

"If you are holding it up to your head to speak a lot, it makes no sense it is having a direct effect on your testes," he added. "Maybe people who use a phone for four hours a day spend more time sitting in cars, which could mean there is a heat issue. It could be they are more stressed, or more sedentary and sit about eating junk food getting fat. … Those seem to be better explanations than a phone causing the damage at such a great distance."

The sperm study won’t be the last on the issue of health disorders and cell phones. If a link is ever proven, the problems could amount to a public health crisis: according to figures included in the BBC article, almost 1 billion people use cell phones around the world and the number is growing in many countries at 20-30 percent annually, according to the BBC. In another five years, the number of mobile phone users is predicted to double.

Until there are clear answers about the danger – if any – the ergonomic approach for cell phone users who want to stay on the safe side of the debate is to use the devices with due caution.

Sources: Globe & Mail; BBC; The Ergonomics Report™