世界衛生組織的專家們指出：手機可能是致癌的，和殺蟲劑DDT及汽車尾氣一樣（圖）

Cellphones could be just as carcinogenic as the pesticide DDT or gasoline engine exhaust, a World Health Organization panel said Tuesday after reviewing dozens of published studies.

While studies so far do not show definitively that cellphone use increases cancer risk, "limited" scientific evidence exists to suggest that the radiofrequency energy released by cellphones may increase the risk of two types of cancers: glioma, a type of brain cancer, and acoustic neuroma, a tumor of the nerve that runs from the ear to the brain, according to the International Agency for Research on Cancer (IARC), which develops scientific cancer-prevention strategies for the WHO.

Scientists have long debated the potential cancer risk linked to cellphone use, but this statement marks the first time an independent group of scientists has taken anything other than a neutral stand.

"My first reaction was, `But, of course,' " said Blake Levitt, a science journalist from Warren who has followed the evolution of cellphones. "The information has been there for a very long time."

But others say the panel's new classification of cellphones does not mean they cause cancer.

IARC ruled that cell phones were "possibly carcinogenic," the third strongest designation on its carcinogen rating scale. The agency's other four categories for substances or agents are: carcinogenic to humans, probably carcinogenic to humans, not classifiable and probably not carcinogenic to humans.

"IARC conducts numerous reviews and in the past has given the same score to, for example, pickled vegetables and coffee," said John Walls, vice president for public affairs for CTIA-The Wireless Association, an industry group. "This IARC classification does not mean cellphones cause cancer."

Bridgeport Hospital neurosurgeon Kenneth Lipow said before anyone throws out their cellphone, they should know it's a "very tenuous" link.

"There aren't any really good medical studies that absolutely prove there is a medical connection, and they put it in the same category as smog," Lipow said.

If anything, cellphones pose a safety issue, not a disease issue, he said. Many more people are hurt in distracted driving incidents than by the brain tumors they may cause, he said.

Kenneth Dressler, chief of oncology and hematology at St. Vincent's Medical Center in Bridgeport, said existing studies have only examined the cellphone usage of people who already have brain cancer. He said a random sample of cellphone users should be followed over time to see how many develop brain cancer.

Because brain cancer tends to be slow growing and cellphone technology is just more than a decade old, it will take a few more decades until any substantial conclusions can be drawn, said Tarek Sobh, vice president of research at the University of Bridgeport.

Many cellphone users said they would not change their habits because of the panel's recommendation.

Teacher Judy Savitt, 71, of Bridgeport, said she thought the IARC's recommendation was blown out of proportion.

"At my age, it's not going to make any difference," she said.

Fairfield University student Craig Borge, 21, said he ignored the findings. "I don't really pay attention to that stuff that much," Borge said. "I don't really have enough knowledge about it. I'm not too worried about it."

Even if cellphones were directly linked to cancer, recent college graduate Sarah Tung, 23, of Fairfield, said she was unlikely to use her phone any less.

"It's my lifeline," said Tung who sleeps with the phone next to her pillow. "I go everywhere with it. It's how I talk to everybody. I don't know what I would do without it."

長期不當使用手機有致腦腫瘤的風險

科學家以前指出過，長期使用手機可增加腦部癌症風險。但世界衛生組織對手機的安全性進行的一項為期10年的研究得出的結論不再認為“手機確實會引發癌症”，因為相關證據不足以給手機的危害蓋棺定論。雖然為了研究手機對人類健康產生的影響，他們在過去10年間耗費了1500萬英鎊，但是這篇論文的作者們不得不承認，還需要進一步研究這種影響，才能給出最終定論。

　　世界衛生組織的報告要在本周晚些時候才會公布，但是英國兩份全國性的報紙在15日報道指出，它將援引科研證據告訴人們，在至少10年內每天使用手機不少於30分鍾，會使患腦癌的風險增加三分之一。過去10年間，他們一直在13個國家進行這項“通電話”研究，它是迄今為止這方麵規模最大的研究。

　　盡管大家清楚，當把手機放在耳朵上接電話時，手機輻射會被大腦吸收，但是，經常使用手機會危害健康的結論並未得到證實，這可能是因為手機在大眾中普及的時間並不長。在2000年到2004年間，研究人員對近1.3萬人進行了研究，查看他們使用手機的時間長短有什麽不同。這些人中，有一部分人患有腫瘤，有一部分人的身體非常健康。

　　其中有些研究成果已經發表，這些研究顯示，那些承認在10年間每天使用手機至少30分鍾的人，患神經膠質瘤的風險增加了。很多人表示，長腦瘤的一側，正好是他們經常放手機接聽電話的腦袋一側。

　　另外，這項研究的另一個發現也存在很大疑問：短期內使用手機事實上有助於預防癌症。即使論文作者也認為這種情況的可能性不大。對於這個問題，他們還要進行更多研究才能得出最終結論，他們尤其要在年輕人之間展開調查。

　　英國衛生部雖然在4年多時間裏一直沒更新相關指南，但該部指出，成年人應該勸阻兒童少打閑聊電話，成人應該盡量“長話短說，縮短通話時間”。其他國家也采取了相應措施，例如鼓勵人們使用耳機接電話、利用發短信代替打電話，或者禁止向兒童推銷手機。