Research by the team at the University of Essen in Germany found that people who regularly use a mobile phone are three times more likely to develop cancer of the eye.
The scientists examined 118 patients who each suffered from uveal melanoma--a cancer that grows in the iris and base of the retina of the eye. They compared the history of mobile phone use of this group with the history of a control group of 475 people.
Analysis of the results, which were published in January's Epidemiology journal, found that those with cancer had a much higher rate of mobile phone use.
However, Dr. Andreas Stang, who led the team of researchers, cautioned that the study needs to be confirmed--a point backed up by Epidemiology.
"Given the small size of their study, the relatively crude exposure assessment, the absence of attention to...other possible confounding variables and limited support in the literature, a cautious interpretation of their results is indicated," read an editorial accompanying the research.
A spokesman for the Federation of Electrical Industries, an industry body for mobile phone companies, insisted that the findings of the Essen group need to be reproduced in subsequent studies.
"This is only preliminary research, and only one among lots of studies which have come to different conclusions. These results need to be replicated," he said.
In the abstract that summarized its research, the Essen group agreed that its research alone does not fully prove a link. "Several methodologic limitations prevent our results from providing clear evidence on the hypothesized association," the group acknowledges.
In December, an American study into a possible link between mobile phone use and cancer failed to find a connection, but did suggest that more research over a long time frame is needed.
Earlier this month, a team at a Spanish university announced that mobile phones have a greater effect on human brain cells than was previously thought. The scientists, based at Madrid's University Complutense, discovered that a cell's nonspherical shape increases the intensity of the electric field generated within it by a mobile phone.
And writing in The Lancet in December, British scientist Dr. Gerard Hyland warned that children are at the greatest risk from mobile phone radiation--specifically from low-intensity, pulsed radiation that could affect a number of brain functions.