Have you heard, cellphones are deadly. Science told us so this week when Dr. Ronald B. Herberman of the esteemed University of Pittsburgh Cancer Institute realized that cellphones emit death rays that fry your brain and turn you into a baby-eating Communist, or give you cancer or whatever. Dr. Despair isn't a downer though! Inside, 10 practical ways to keep your precious little brain safe from those ubiquitous chirping cancer slabs...

1. Do not allow children to use a cell phone, except for emergencies. The developing organs of a fetus or child are the most likely to be sensitive to any possible effects of exposure to electromagnetic fields.

2. While communicating using your cell phone, try to keep the cell phone away from the body as much as possible. The amplitude of the electromagnetic field is one fourth the strength at a distance of two inches and fifty times lower at three feet. Whenever possible, use the speaker-phone mode or a wireless Bluetooth headset, which has less than 1/100th of the electromagnetic emission of a normal cell phone. Use of a hands-free ear piece attachment may also reduce exposures.

3. Avoid using your cell phone in places, like a bus, where you can passively expose others to your phone's electromagnetic fields.

4. Avoid carrying your cell phone on your body at all times. Do not keep it near your body at night such as under the pillow or on a bedside table, particularly if pregnant. You can also put it on “flight” or “off-line” mode, which stops electromagnetic emissions.

5. If you must carry your cell phone on you, make sure that the keypad is positioned toward your body and the back is positioned toward the outside so that the transmitted electromagnetic fields move away from your rather than through you.

6. Only use your cell phone to establish contact or for conversations lasting a few minutes, as the biological effects are directly related to the duration of exposure. For longer conversations, use a land line with a corded phone, not a cordless phone, which uses electromagnetic emitting technology similar to that of cell phones.

7. Switch sides regularly while communicating on your cell phone to spread out your exposure. Before putting your cell phone to the ear, wait until your correspondent has picked up. This limits the power of the electromagnetic field emitted near your ear and the duration of your exposure.

8. Avoid using your cell phone when the signal is weak or when moving at high speed, such as in a car or train, as this automatically increases power to a maximum as the phone repeatedly attempts to connect to a new relay antenna.

9. When possible, communicate via text messaging rather than making a call, limiting the duration of exposure and the proximity to the body.

10. Choose a device with the lowest SAR possible (SAR = Specific Absorption Rate, which is a measure of the strength of the magnetic field absorbed by the body). SAR ratings of contemporary phones by different manufacturers are available by searching for “sar ratings cell phones” on the internet.

Of course, science doesn't actually know for certain whether cellphones are safe or whether they cause debilitating brain tumors. "Further research is needed" is a common refrain, though this is the sort of thing that will work itself out over the next decade as more, um, tumors data become available.

1. 除非紧急情况，否则不要让孩子使用手机。胎儿或者小孩正在发育的器官相对来说更容易受到电磁场辐射的影响。

2. 打电话的时候，尽量让手机尽远离身体。电磁场的振幅在两英寸距离强度为1/4，3英尺的距离则降低到为1/50。可能的话，尽可能的使用免提模式或者蓝牙耳机，它受到辐射的干扰程度仅是普通手机的1/100。使用耳机听筒也可减少辐射。

3.避免在公共汽车上使用手机，因为公共汽车上的其他人将被迫受到你的手机辐射影响

4. 避免一直随身携带手机。晚上不要将手机放在身边、枕头底下或者桌子旁边，尤其是孕妇。可以将手机关机或者调到飞行模式，这样手机就不会发出电磁场辐射来。

5. 如果你必须随身携带手机，注意将手机键盘朝向自己的身体，手机背面向外，这样手机电磁波就会向外传输，而不是传输给你的身体。

6. 不要长时间连续使用手机通话，因为电磁波的生理影响和辐射的时间长度直接相关。如果需要长时间通话，尽量使用固定电话，但不要使用无绳电话，因为后者和手机采用相近的电磁传播技术

7. 用手机打电话时注意经常换边。拨打电话时等对方接听之后再将手机放到耳边，这样可以减少电磁辐射字你耳边的持续时间。

8. 不要在信号不好或者高速移动时，比如在汽车或者火车上，使用手机。因为这种情况下手机必须不断接入到新的基站。

9. 尽可能用手机发短信，不打电话。这样可以限制辐射的时间和电磁波到身体的距离。

10. 尽可能选择SAR值低的手机。（SAR是英文Specific Absorption Rate<比吸收率>的缩写，是衡量电磁场强度被身体吸收量的一个标准。）在网上搜索“sar ratings cell phones”可以找到各种手机的SAR值。

当然，科学并不能一定确定知道手机是否安全，或者手机是否使人类大脑受损。“进一步的研究是有必要的”这话被不同的人说过不止一次，但这却是那种在十年之后届时更多的,呃...脑瘤资料能够利用时,自己便可以解答出来的事情。