LONDON (AP) _ A respected international panel of experts says cellphones are possible cancer-causing agents, putting them in the same category as the pesticide DDT, gasoline engine exhaust and coffee.
The classification was issued Tuesday in Lyon, France, by the International Agency for Research on Cancer after a review of dozens of published studies. The agency is an arm of the World Health Organization and its assessment now goes to WHO and national health agencies for possible guidance on cellphone use.
Classifying agents as ``possibly carcinogenic'' doesn't mean they automatically cause cancer and some experts said the ruling shouldn't change people's cellphone habits.
``Anything is a possible carcinogen,'' said Donald Berry, a professor of biostatistics at the M.D. Anderson Cancer Center at the University of Texas. He was not linked to the WHO cancer group. ``This is not something I worry about and it will not in any way change how I use my cellphone,'' he said _ from his cellphone.
After a week-long meeting, the expert panel said there was limited evidence cellphone use was linked to two types of brain tumors and inadequate evidence to draw conclusions for other cancers.
``We found some threads of evidence telling us how cancers might occur, but there were acknowledged gaps and uncertainties,'' said Jonathan Samet, the panel's chairman.
``The WHO's verdict means there is some evidence linking mobile phones to cancer but it is too weak to draw strong conclusions from,'' said Ed Yong, head of health information at Cancer Research U.K. ``If such a link exists, it is unlikely to be a large one.''
Last year, results of a large study found no clear link between cellphones and cancer. But some advocacy groups contend the study raised serious concerns because it showed a hint of a possible connection between very heavy phone use and glioma, a rare but often deadly form of brain tumor. However, the numbers in that subgroup weren't sufficient to make the case.
The study was controversial because it began with people who already had cancer and asked them to recall how often they used their cellphones more than a decade ago.
In about 30 other studies done in Europe, New Zealand and the U.S., patients with brain tumors have not reported using their cellphones more often than unaffected people.
Because cellphones are so popular, it may be impossible for experts to compare cellphone users who develop brain tumors with people who don't use the devices. According to a survey last year, the number of cellphone subscribers worldwide has hit 5 billion, or nearly three-quarters of the global population.
People's cellphone habits have also changed dramatically since the first studies began years ago and it's unclear if the results of previous research would still apply today.
Since many cancerous tumors take decades to develop, experts say it's impossible to conclude cellphones have no long-term health risks. The studies conducted so far haven't tracked people for longer than about a decade.
Cellphones send signals to nearby towers via radio frequency waves, a form of energy similar to FM radio waves and microwaves. But the radiation produced by cellphones cannot directly damage DNA and is different from stronger types of radiation like X-rays or ultraviolet light. At very high levels, radio frequency waves from cellphones can heat up body tissue, but that is not believed to damage human cells.
Some experts recommended people use a headset or earpiece if they are worried about the possible health dangers of cellphones. ``If there is a risk, most of it goes away with a wireless earpiece,'' said Otis Brawley, chief medical officer of the American Cancer Society.
Brawley said people should focus on the real health hazards of cellphones. ``Cellphones may cause brain tumors but they kill far more people through automobile accidents,'' he said. Brawley added it was also reasonable to limit children's use of cellphones since their brains are still developing.
Earlier this year, a U.S. National Institutes of Health study found that cellphone use can speed up brain activity, but it is unknown whether that has any dangerous health effects.
In the U.S., the Food and Drug Administration and the Federal Communications Commission have found no evidence cellphones are linked to cancer.
"휴대전화사용, 암발병 위험 높여"
세계보건기구(WHO) 산하 국제암연구소(IARC)는 휴대 전화를 사용할 경우 일부 뇌종양의 발생 위험이 증가한다면서 휴대전화 사용자들은 위험 노출을 줄이는 방법을 고민해야 한다고 31일 밝혔다.
14개국 31명의 전문가로 구성된 IARC 실무 그룹은 가능한 모든 과학적 증거를 검토한 결과 휴대전화 사용은 암을 유발할 수 있는 경우로 분류돼야 한다고 말했다.
IARC 전문가들이 휴대전화 사용을 발암 가능성이 있는 경우로 분류하게 되면 WHO는 휴대전화 이용 가이드라인을 다시 검토하게 된다.
하지만 IARC전문가들은 휴대전화 사용과 암발생 연관성에 대해 명확한 해답을 내놓기 위해서는 보다 많은 연구가 이뤄져야 한다고 지적했다.
WHO는 그동안 휴대전화 이용과 암발병 간 상관관계를 보여주는 확실한 증거는 없다는 입장을 보여왔다.
조너선 새멋 IARC 소장은 "관련 증거를 검토한 결과 실무 그룹은 무선 전자기장 이 인체에 암을 유발할 수 있는 것으로 분류했다"며 일부 증거들은 휴대전화 사용과 뇌종양의 한 형태인 신경교종의 위험 증가에 상관 관계를 보여준다고 밝혔다.
이 같은 IARC의 의견은 휴대전화 업계에 상당한 파장을 줄 것으로 예상된다.
휴대전화는 1980년대 초중반 처음 소개된 뒤 사용자가 급증하기 시작해 현재 50억명 정도가 휴대전화를 이용하는 것으로 추정되고 있다.