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Are cell phones harmful? Do cell phones cause cancer? These are questions we ask ourselves each time we hear the latest research results in the news, but we are still not sure if the answer is “Yes” or “No”. We’ve seen several documentaries about people suffering from brain tumors, saying that the main source of their illness is the large amount of time they have been exposed to cell phones radiation. The ones affected by this type of tumor used to talk on the phone maybe over 80% of the day time, as they were very busy people with high soliciting jobs, requiring many hours spent on talking and making important decisions from distance.

According to the American Cancer Society, the cell phone usage has spread worldwide since just 10 years, which is too short to be able to determine long-term health effects. During the last years, researchers have analyzed the differences between people affected by brain tumors that have been using cell phones, and those that are healthy and use the device. Results are unconcludent yet, but they seem to reveal the non-harmful side of the mobile phone use. Patients with brain cancer didn’t use the cell phones more often than the healthy ones, and intensive cell phone users do not show signs of this illness as it should if the radiation would be a cause for it. Also, these studies couldn’t link the side of the head with brain tumor with the side on which the mobile phone was used.

According to Wikipedia, until today there were several studies published including the following:



2004-The Danish study that took into consideration 10 years of cell phones use and found no sign revealing that humans can be affected by this type of radiation;
2005-The Swedish study showing that "the data do not support the hypothesis that mobile phone use is related to an increased risk of glioma or meningioma.";
2005-The British study concluding that "The study suggests that there is no substantial risk of acoustic neuroma in the first decade after starting mobile phone use. However, an increase in risk after longer term use or after a longer lag period could not be ruled out."
2006-The German study stating that "no overall increased risk of glioma or meningioma was observed among these cellular phone users; however, for long-term cellular phone users, results need to be confirmed before firm conclusions can be drawn.";
The INTERPHONE study conducted by Japan researchers who looked for brain tumor risks influenced by cell phones use. It tried to determine the SAR level inside tumors by calculating the RF level absorption in glioma, meninigioma, and pituitary adenoma. They didn’t find any proof to sustain the idea of cell phones use influencing tumor development.
Other studies, like Dr. Vini Khurana’s, showed that using cell phones more than 10 years doubles the risk of brain cancer, but it was highly criticized as there was no clear evidence.

Now if we take a look at the evolution of wireless safety standards, we’d realize that they have become stricter over time, which might suggest a possible concern over cell phone usage effects:
-1966: The ANSI C95.1 standard adopted the standard of 10mW/cm2 (10,000 μW/cm2) based on thermal effects.
-1982: The Institute of Electrical and Electronics Engineers recommended further lowering this limit to 1mW/cm2 (1,000 μW/cm2) for certain frequencies in 1982, which became a standard ten years later in 1992 (see below).
-1986: The National Council on Radiation Protection & Measurements recommended the exposure limit of 580 μW/cm2.
-1992: The ANSI/IEEE C95.1-1992 standard based on thermal effects used the 1mW/cm2 (1,000 μW/cm2) safety limit. The U.S. Environmental Protection Agency called this revised standard "seriously flawed", partly for failing to consider non-thermal effects, and called for the FCC to adopt the 1986 NCRP standard which was five times stricter.
-1996: The FCC updated to the standard of 580 μW/cm2 over any 30-minute period for the 869 MHz, while still using 1mW/cm2 (1,000 μW/cm2) for PCS frequencies (1850-1990 MHz).[59]
-1998: The ICNIRP standard uses the limit of 450 μW/cm2.
Not all cell phone models on the market spread the same amount of radiation. To find out about each model radiation level you should have to look for the Specific Absorption Rate level in the cell phone’s specifications, which shows the rate at which RF energy is absorbed by your body when exposed to the RF electromagnetic field.



Let’s clarify how this happens!
When you make a call the handset tries to contact the base station, also called cell phone tower, and this one responds with the same type of signals known as radio waves, so the enviroment is exposed to these waves circulating over the air. The antennas from the base stations have high power levels but the radio waves intensity is very low at the ground level , where you try to make the call.
To protect people from the RF radiation, the agencies responsible with public protection have set some standards: the exposure limit has to be in the range of 0.41-0.45 milliwatts per square centimeter, the power density inside buildings on top of which base stations are mounted is up to 100 times lower than the level outside because of special construction materials used, and as the power density behind the antennas is up to thousands of times lower than in front, the antenna are mounted on a side of the building.

But what about the cell phone towers?
When the cell phone communicates with the cell phone towers through radio waves, the energy consisting of photons sent in packages and measured in electron Volts doesn’t exceed one millionth of an eV, which is too small to be able to affect body molecules.
To cause cancer the radiation has to affect the body cells. Radio waves length is of 1 foot in the air and 2 inches in body tissue, which can’t be concentrated on small parts of tissue. Body cells are even smaller.
Another aspect is the magnitude of exposure, and tests showed that people are exposed at RF radiation related to cell phones at the same level as other sources like radios and television broadcast stations.
Also, not all of you are aware of the fact that when the cell phone has a high signal strength the power output is 1000 times lower than when the signal is poor.



Back to the SAR. The Specific Absorption Rate is calculated on 1 gram or 10 grams of tissue, and measures the exposure in fields between 100kHz and 10 GHz.
Governments that took measures against this possible problem set clear SAR limits, such as the United States that requires the SAR to be below 1.6 W/Kg in 1 gram of tissue, or the European Union that asks for maximum 2 W/Kg at 10 grams of tissue, with 0.08 W/Kg average exposure over the whole body.
These are the methods you can reduce your exposure to the radiation when using cell phones: call only when you need, make only short calls, send text messages as often as possible, don’t use your cell phone when the signal strength is low, use the phone outside or close to a window, switch off the phone when not in use.

To give you a few examples of the latest cell phone models’ SAR levels, Nokia E51 has 1.47 W/kg, Nokia N95 has 0.50 W/kg, Samsung Instinct has 1.16 W/kg for the head and 1.220 W/kg for the body, Sony Ericsson C902 has 1.32 W/Kg, and Motorola MOTO W755 has 0.8 W/Kg.

(Sources: Mobile Phones UK; Wikipedia; American Cancer Society)

What is a Mobile Phone?
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Everybody knows what a cell phone is so I’ll be short. A mobile phone, as its name suggests, is a portable device with wireless transmission, which anyone can use while on the go. You can use one for making phone calls, receive phone calls, which is its main function, but you can also transfer and receive files with music, videos, images and, of course, text.

Cellular Phone Parts

After making a mobile phone research, I am inviting you inside the cell phone to see its components.

First take a look at your own model. What do you see? It has a Liquid Crystal Display, a keypad like the one on your TV remote, while inside it has an antenna (which can be external and visible at some models), a removable battery, a microphone, a speaker, and another thing that you can’t see if you don’t disassembly the handset is the circuit board, in charge with processing the commands you type.



On the circuit board, a specialist can identify easily the conversion chips that translate the analog audio signal emitted when you are in a phone call, into digital signal, and the digital signal that comes to your handset over the air, back into analog. The smart piece that handles the digital signal is called the Digital Signal Processor, which uses complex algorithms to make calculations in order to transform the analog and digital signals in real time.



Same as personal computers, cell phones have also a microprocessor that handles the commands from the keyboard making them displayable on the LCD.
The operating system and directories are kept in the Random Access Memory and Flash memory chips, while the power issues are controlled by the Radio Frequency and the power area.
Cell phone speakers are incredibly small, as well as microphones, but with the latest technologies they have powerful capabilities.

Cell Phone Manufacturing

The manufacturing process involves 40% metals, 40% plastics and 20% ceramics and trace materials, while the circuit board uses copper, lead, nickel, gold, zinc, beryllium, tantalum, coltan and others. Some of the raw materials are processed before the cell phone manufacturing, like the crude oil used for plastics, which has to be mixed with natural gas and chemicals in a special plant. The copper, for example, has to be mined, ground, heated and treated with chemical substances and electricity, in order to isolate the pure metal used also in batteries.
Cell Phone Screens with LCDs have liquid crystalline substances like mercury, and are sandwiched between glass and plastic layers. The batteries have the two electrodes made of metals.

This is a cell phone diagram for your curiosity:



How Does a Mobile Phone Work?

How does a cell phone work? This is simple. If a standard radio uses a simplex communication system so that you can hear the moderator talking, without having the possibility to reply, a cell phone is a duplex device permitting you to talk to the person who started the call. It sends and receives radio signals using cell sites located on specially built towers, poles or buildings, all being connected to a large cabled network with a switching system. The smart thing is that cell phones send data to the nearest cell sites located at maximum 13 Km away, this after they are turned On, moment when it registers with the switch, using a unique identifier.



When you are on the go, carrying your phone with, it is permanently detecting the strongest signals from the base stations, so if a signal weakens, the handset care is passed to the nearest cell site.
Your cell phone receives the phone call from a friend and this digital signal is transformed into analog signal, processed by the Digital Signal Processor, and finally amplified via the built-in speaker. When you talk, the voice is detected by the small microphone as analog, processed, and in the end transformed into digital signal to be sent over the air.

The SIM card is a microchip called a Subscriber Identity Module, and the phone is dependent on it to work. It is in charge with storing information like the calling plan and other phone’s details, while having a unique numerical identifier used to lock the device permanently after the first activation.

History of the Cell Phone

Who Invented the Cell Phone? If you want to know who was the first who got the idea of creating a cellular phone the answer is the American Telephone & Telegraph which is no other than AT&T from the United States, which was the world's largest telephone company and the world's largest cable television operator, with $300 billion dollars revenue. It was purchased by Baby Bell SBC Communications in 2005.

In April 1973, Dr Martin Cooper, former general manager for the systems division at Motorola, invented the mobile phone prototype and made the first call to Joel Engel, his rival, head of research at Bell Labs.



Copper was a project manager at Motorola and the world’s first mobile phone was Motorola Dyna-Tac, a 2.5 pounds handset measuring 9 x 5 x 1.75 inches, featuring 30 circuit boards, 35 minutes talk time, 10 hours recharge time, and having just three functionalities: dial, talk and listen. He, together with his colleagues, published the patent for the world’s first portable duplex radio telephone system.



AT&T’s concept couldn’t pass by the monopoly on the wired service in the US in 1915, so someone else had to finalize this, and the answer for your next question - When was the first mobile phone invented? - is the year 1978 and the place Japan. There, the Nippon Telegraph and Telephone Corporation, known as the most popular cell phone operator in the country, NTT DoCoMo, created the world’s first commercial cell phone.

There are different types of mobile phones. Nokia Communicator launched in 1996 was the world’s first cell phone with Internet connectivity and email functionality. The same company created the world’s first Smartphone.
NTT DoCoMo launched i-Mode, the first mobile Internet service, in 1999 in Japan.
The first http://en.wikipedia.org/wiki/Short_message_service Short Message Service message was sent in 1992 in the United Kingdom, but from a computer to a cell phone, and the first text message sent from a phone to another phone was in 1993 in Finland.

How many people own cell phones at this moment? We can’t be sure about the number, but at the end of last year there were 3.3 billion subscribers worldwide, meaning half of the population on the globe, and if you take into account the fact that maybe 50% of them own more than one cell phone, you could imagine a higher number, of almost 4.5 billion. The cellular phone technology is the most widely spread and the most popular gadget in the world.

This is a sponsored review for The Phone Spot, ordered through ReviewMe. But, as I mentioned before, the fact that it was paid has nothing to do with the opinions expressed here, which are ours and are not influenced in any way.

So, let's see what this is about. Well, according to them, The Phone Spot is a website meant to make buying mobile phones, home phones and broadband online as easy as possible. They are a part of The Carphone Warehouse, UK's largest mobile phone retailer, so this is a good sign that the services they offer are worth it. So let's take a look and see if this is true.

A very interesting service is the step-by-step PhoneFinder. This allows you to search for the right phone for you, depending on your needs and style and see any available offers for it. So let's see how it works. Here's a screenshot with what I want from my phone.



And here are the results I got:



In my opinion the results aren't very satisfying, but I like that the Blackberry 8100, a phone which I like, is on the list. So, after you select a phone from the results, you can see almost every offer available for the phone, and you can also sort the results depending on how many minutes or text messages you use, or what time you make your calls (during work day, in the evening or in weekends). After you decide on a package, you can purchase it directly through the website.

Overall, The Phone Spot looks like a good place to find a mobile phone and a right package for you, even though I wasn't very satisfied with the search results, but once you decide on a phone, or have a phone in mind, the website is very useful, allowing UK users to find the best offer available for them; and the fact that it's a part of The Carphone Warehouse indicates that this is a quality service. Of course, if any of our readers used them and wants to share an opinion, please do.

This is a paid review from DialToSave, ordered through ReviewMe. But don't be alarmed, this is not an advertisment, it is simply a review, with my own opinions, not influenced in any way by DialToSave.

So, let's see, first of all, who is DialToSave? According to what they say, DialToSave is a website that "has been offering advice on the various options available to people interested in other communications services, in particular the cheapest mobile phone deals" since September 2005. experience with DialToSave.

The services they want to offer are very useful and the first impression is that they do it very good. On the front page we have the top 3 free mobile phones deals, which currently are some pretty good offers from Orange and Vodafone for Samsung U600 and Sony Ericsson K800i. But their list of deals that offer free mobile phones is much longer and it can be seen in the "Mobile Phones Deals" section. You can also sort the deals, depending on the carrier or the phone manufacturer (for example, click here to see the Samsung deals)

An interesting service is the International Phone Calls service. This allows you to make cheap international phone calls with prices from 3p/min to 10p/min. These rates are available using access numbers and you can call almost everywhere in the world. Before doing that, you have a section where you can select the country you want to call to, and then you'll see the rates for calling there, depending on your carrier plus the access numbers you need to access.

Another interesting service and useful, in my opinion, is the cashback reminder. As you probably know, many retailers offer cashback with their mobile phone deals, and I doubt that you'll remember to claim the cashback, sometime between 12 and 18 months after you purchase the deal (I know I wouldn't). So what does this service offer? You register, enter the details of when you received your phone and from which retailer and they'll send you an e-mail when it's the time to claim the cashback.

Overall, DialToSave looks like a good service for UK residents, but I never used them, so my opinions are only based on what I read on their website, www.dialtosave.co.uk. If any of our readers used their services, please share with us your personal experience.