WARNING: Holding a cellphone against your ear or storing it in your pocket may be hazardous¹ to your health.

警告：将手机贴在耳边或者塞在口袋里可能有害健康。

This paraphrases² a warning that cellphone manufacturers include in the small printthat is often tossed aside when a new phone is purchased. Apple, for example, doesn't want iPhones to come closer to you than 1.5 centimeters; Research In Motion, BlackBerry's manufacturer, recommends 2.5 centimeters.

在消费者购置新机后，常对手机厂商印在不起眼位置的小字警告不以为然。例如，苹果公司提醒称iPhone手机距离人体至少要有1.5厘米，黑莓手机生产商RIM公司建议最小距离为2.5厘米。

If health issues arise from cellphone use, the implications are huge. Voice calls - Americans chat on cellphones 2.26 trillion minutes annually³ - generate $109 billion for the wireless⁴ carriers.

如果手机使用可导致健康问题，后果将很严重。美国每年手机通话的时长共计2.26万亿分钟，这些语音通话为无线运营商带来了1090亿美元的收入。

Devra Davis, an epidemiologist who has worked for the University of Pittsburgh, has published a book about cellphone radiation, "Disconnect." The book surveys scientific research and concludes the question is not settled.

匹兹堡大学的流行病学专家德芙拉 戴维斯出版了一本有关手机辐射的书《关机》。这本书对有关科学研究进行了调查，其结论是：这个问题还没有定论。

Brain cancer is a concern that Ms. Davis examines. Over all, there has not been an increase in its incidencesince cellphones arrived. But the average masks an increase in brain cancer in the 20-to-29 age group and a drop for the older population.

脑癌是戴维斯女士研究的辐射后果之一。总体而言，自手机出现以来，脑癌发病率并未上升。但这一平均率掩盖了如下事实：脑癌在20至29岁年龄群体中的发病率增加，而在老年人群中的发病率下降。

"Most cancers have multiple causes," she says, but she points to laboratory research that suggests low-energy radiation could damage cells that could possibly lead to cancer.

她说：“大多数癌症具有多种病因。”但她指出，实验室研究表明，低能辐射会损害人体细胞，而这又有可能导致癌症。

Children are more vulnerable to radiation than adults, Ms. Davis and other scientists point out. Radiation that penetrates⁵ only five centimeters into the brain of an adult will reach much deeper into the brains of children because their skulls⁶ are thinner and their brains contain more absorptive fluid. No studies have yet been completed on cellphone radiation and children, she says.

戴维斯女士及其他一些科学家指出，儿童比成人更容易受到辐射的影响。由于儿童的颅骨更薄，而且大脑中含有更多易吸收辐射的液态物质，因此渗入成人大脑仅5厘米的手机辐射能够渗入到儿童大脑内更深的区域。她表示，手机辐射对儿童影响方面的研究目前还不完善。

Henry Lai, a research professor in the bioengineering department at the University of Washington, began laboratory radiation studies in 1980 and found that rats exposed to radiofrequency radiation had damaged DNA⁷ in their brains.

华盛顿大学生物工程系研究教授赖亨利自1980年开始进行辐射实验研究。他发现，受到射频辐射的实验鼠脑组织DNA会受损。

Ms. Davis recommends using wired headsets or the phone's speaker. Children should text rather than call, she said, and pregnant women should keep phones away from the abdomen⁸.

戴维斯女士建议大家使用有线耳机或手机扬声器，儿童应尽量收发短信而不是打电话，而怀孕妇女应将手机远离腹部。