手机被定为"可致癌物质" 堪比杀虫剂

　　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.

　　同时，该项研究还备受争议，因为研究者一开始就研究对象就是已经患上癌症的病人，并且要求病人回忆在最近十年中使用的频率。

　　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.

　　大概有30份其他的研究是在欧洲、新西兰和美国所完成的，患有神经胶质瘤的病人并没有表示他们比没有患病的人使用手机的频率高。

　　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.

　　因为手机的使用过于广泛，以至于专家们难以将使用手机而又患有神经胶质瘤的人与那些不使用这种通信设备的人的情况进行比较。据一份去年的调查研究称，全球的手机用户总数已经达到了50亿之多，也就是将近地球人口中的四分三都在使用手机。

　　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.

　　第一份使用手机的研究问世于几年以前，不过在那之后，人们使用手机的习惯发生了巨大的改变，所以之前研究的结果在现今是否还具有意义，这一点尚不清楚。

　　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.

　　因为很多癌症肿瘤需要几十年的时间来形成，所以有专家称很难断定长期使用手机所带来的健康危害。目前的这些研究对于目标群体的跟踪调查均未超过10年的时间。

　　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.

　　手机党工作原理是这样的：它会发射出射频电波，将手机信号发送到最近的信号塔上。不过由手机所产生的辐射并不能直接对DNA产生危害，并与X射线、紫外线遮阳高强度的辐射不同。只有在手机信号非常强烈的时候，才会对于人体的组织加热，但是这也不足以怕坏人体细胞。

　　According to Cancer Research U.K., the only health danger firmly connected to cellphones is a higher risk of car accidents. The group recommends children under 16 only use cellphones for essential calls because their brains and nervous systems are still developing.

　　Also, a recent 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.

　　据英国癌症研究中心称，唯一与使用手机有确凿的练习的健康危险是，因为开车时使用手机而引发的车祸。这家机构建议16岁以下的少年只有在非常情况之下才使用手机，因为他们的大脑以及神经系统仍处于发育阶段。同时，美国国立卫生研究院在最近研究发现，使用手机会加快大脑的活动，此外还上不清楚有任何危害健康的影响。