In 2008, a claim was made that the RF energy from two mobile phones can cook an egg in 60 minutes.
In fact this is impossible. Even if you assume that each mobile phone is emitting RF energy at its maximum average power of 0.25 W (based on a peak power of 2 W per phone) for 60 minutes; and even if the total power (2 X 0.25 W = 0.5 W) of both phones was completely absorbed by the egg (assuming it weighs 50 g), then the result would be a maximum temperature rise after 60 minutes of only 13 °C. Even if the egg was at room temperature before starting the experiment, the result would still be far below the temperature actually needed to cook an egg (which is approx. 65 - 70 °C).
In reality, an egg placed between two phones would have a much lower temperature rise because the egg is not thermally insulated and it would only absorb a small portion of the energy emitted. In October 2007 the Australian Centre for RF Bioeffects Research (ACRBR) conducted an experiment to de-bunk the myth that cell phone exposure can cook an egg. The video can be downloaded from http://www.acrbr.org.au/ScienceWeek.aspx
For more information download our Viewpoint on the Cooking an egg by two mobile phones Hoax.
Like the hoax about cooking an egg, mobile phones are also incapable of cooking popcorn as they do not generate anywhere near enough RF energy to pop the corn. We can demonstrate this as follows: even if you assume that each mobile phone is emitting RF energy at its maximum average power of 0.25 W (based on a peak power of 2 W per phone) for 1 minute; and even if the total power of each phone (4 * 0.25 W = 1 W) was completely absorbed by the popcorn then the temperature rise will be minimal and still far below the 190 °C temperature actually needed for cooking popcorn.
In reality, a microwave oven of about 1000 Watts takes anywhere from 30 seconds to a minute to cook popcorn. As indicated above, even with three or four phones, the total power is at least a 1000 times below what would be required. For more information download our Viewpoint on the mobile phone popcorn hoax.
Another popular myth is that mobile phones can cause explosions at petrol stations. According to the UK Institute of Petroleum, there is no evidence that a mobile phone has ever caused an explosion at a petrol station anywhere in the world.
This is because the amount of radio frequency energy emitted from mobile phones is too low to cause a spark that could ignite petrol. In 1991 Shell UK assessed the risks of a radio frequency spark from mobile phones and had found that mobile phones did not represent a meaningful hazard. By far the greatest hazard, apart from smoking and striking matches, was the car.
There have been many devices such as shields and 'absorbing buttons or stickers' that have claimed to reduce EMF emissions from mobile phones.
As a mobile phone automatically operate on the lowest power necessary to maintain a quality call, adding a device that interferes with the normal operation of a mobile phone can actually cause it to emit more RF to try to compensate for the interfering object. This can result in decreased battery life and reduced efficiency.
The WHO advice on these products is:
"The use of commercial devices for reducing radiofrequency field exposure has not been shown to be effective."