STOCKHOLM (Reuters) - Swedish researchers say they have found an apparent
link between using mobile telephones and
fatigue, headaches, and tingling and heat sensations on the ear and skin.

In the only comprehensive study to date on the health effects of mobile
phone use, a survey of about 11,000 Swedes and
Norwegians showed the symptoms increased the more frequently people used
their telephones.

However, people who use mobile phones often may also have a stressful
lifestyle, which could be a contributing factor. This
could not be tested by the study.

"People have more complaints when they are using the mobile phone more but
we don't know at the moment what's causing
them, " Kjell Hansson Mild, of Sweden's National Institute for Working Life
in Umea, northern Sweden, told Reuters.

The group surveyed was a random selection of people who had mobile
telephone subscriptions through their employers.

Further studies are required to verify our finding and to explore the role
of the various physical factors," the institute said in a
statement.

Demonstrable statistical associations between both calling time and number
of calls per day and the occurrence of warmth
sensation as well as headache and fatigue were found both among (analog)
NMT users and (digital) GSM users in both
countries."

Finding out if the symptoms could be blamed on the telephones would require
finding people for a control group who have
equally stressful lives but do not use mobiles, Mild said.

Among the Norwegian participants who used a GSM mobile phone 15 to 60
minutes per day, the chance of a complaint of
fatigue was 1.6 times higher than for those who used the phone less than
two minutes per day.

It was 4.1 times higher for those who used the phone more than 60 minutes
per day.

Those who use the phone 15 to 60 minutes daily were 2.7 times more likely
to report a headache and 6.3 times more likely
to have one if they talked more than 60 minutes per day.

Other physical factors may be behind the complaints.

"People are usually standing in a corner trying to press the telephone
against their ear to hear the person speak," Mild said,
adding that holding a phone to the ear probably disrupted blood circulation
in one part of the head.

"If you are using a phone and having these symptoms you might want to
consider your mobile phone use and using your
ordinary phone for longer calls or hands-free equipment for mobiles, thus
taking the phone away from your head."

The Swedish Mobile Telecommunications Association (MTB) said the results of
the survey would be positive for the
industry as it showed no clear link.

"If you have a headache you can't blame it on your phone. Some small group
had more headaches, but they could not tell if
this was caused by stress or some other physical condition," Arvid
Brandberg, head of MTB, told Reuters.

Mobile telephones, like other electrical appliances, do emit heat but this
did not make people feel bad, he added.

Sweden and Norway have some of the highest number of mobile phone users per
capita.

In Sweden, home of mobile telephone maker Ericsson, 36 percent of the
population had mobile telephones at the end of
1997, industry statistics show.