Love To Hang With Smartphones? But Beaware Of Its Dark Sides

Mobile phone radiation and health

A man speaking on a mobile telephone

The effect of mobile phone radiation on human health is a subject of interest and study worldwide, as a result of the enormous increase inmobile phone usage throughout the world. As of November 2011, there were more than 6 billion subscriptions worldwide. Mobile phones useelectromagnetic radiation in themicrowave range. Other digital wireless systems, such as data communication networks, produce similar radiation.

In 2011, International Agency for Research on Cancer (IARC) classified mobile phone radiation as Group 2B - possibly carcinogenic (not Group 2A - probably carcinogenic - nor the dangerous Group 1). That means that there "could be some risk" of carcinogenicity, so additional research into the long-term, heavy use of mobile phones needs to be conducted. The WHO added in June 2011 that "to date, no adverse health effects have been established as being caused by mobile phone use", a point they reiterated in October 2014.Some national radiation advisory authorities have recommended measures to minimize exposure to their citizens as a precautionary approach.

Effects

Many scientific studies have investigated possible health symptoms of mobile phone radiation. These studies are occasionally reviewed by some scientific committees to assess overall risks. A 2007 assessment published by theEuropean Commission Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR)concludes that the three lines of evidence, viz. animal, in vitro, and epidemiological studies, indicate that "exposure to RF fields is unlikely to lead to an increase in cancer in humans".

Radiation absorption

Part of the radio waves emitted by a mobile telephone handset are absorbed by the body. The radio waves emitted by a GSM handset are typically below a watt. The maximum power output from a mobile phone is regulated by the mobile phone standard and by the regulatory agencies in each country. In most systems the cellphone and the base station check reception quality and signal strength and the power level is increased or decreased automatically, within a certain span, to accommodate different situations, such as inside or outside of buildings and vehicles.The rate at which energy is absorbed by the human body is measured by theSpecific Absorption Rate (SAR), and its maximum levels for modern handsets have been set by governmental regulating agencies in many countries. In the USA, the Federal Communications Commission (FCC) has set a SAR limit of 1.6 W/kg, averaged over a volume of 1 gram of tissue, for the head. In Europe, the limit is 2 W/kg, averaged over a volume of 10 grams of tissue. SAR values are heavily dependent on the size of the averaging volume. Without information about the averaging volume used, comparisons between different measurements cannot be made. Thus, the European 10-gram ratings should be compared among themselves, and the American 1-gram ratings should only be compared among themselves. SAR data for specific mobile phones, along with other useful information, can be found directly on manufacturers' websites, as well as on third party web sites. It is worth noting that thermal radiation is not comparable to ionizing radiation in that it only increases the temperature in normal matter, it does not break molecular bonds or release electrons from their atoms.

Thermal effects

One well-understood effect of microwave radiation is dielectric heating, in which any dielectric material (such as living tissue) is heated by rotations of polar moleculesinduced by the electromagnetic field. In the case of a person using a cell phone, most of the heating effect will occur at the surface of the head, causing its temperature to increase by a fraction of a degree. In this case, the level of temperature increase is an order of magnitude less than that obtained during the exposure of the head to direct sunlight. The brain'sblood circulation is capable of disposing of excess heat by increasing local blood flow. However, the cornea of the eye does not have thistemperature regulation mechanism and exposure of 2–3 hours duration has been reported to produce cataracts in rabbits' eyes at SAR values from 100–140 W/kg, which produced lenticular temperatures of 41 °C. There were no cataracts detected in the eyes of monkeys exposed under similar conditions.Premature cataracts have not been linked with cell phone use, possibly because of the lower power output of mobile phones.

Non-thermal effects

The communications protocols used by mobile phones often result in low-frequency pulsing of the carrier signal. While the existence of effects due to the field is undisputable, whether these modulations are causing these effects or these are still of thermic nature is subject to debate.

Some researchers have argued that so-called "non-thermal effects" could be reinterpreted as a normal cellular response to an increase in temperature. The German biophysicist Roland Glaser, for example, has argued that there are several thermoreceptor molecules in cells, and that they activate a cascade of second and third messenger systems, gene expression mechanisms and production of heat shock proteins in order to defend the cell against metabolic cell stress caused by heat. The increases in temperature that cause these changes are too small to be detected by studies such as REFLEX, which base their whole argument on the apparent stability of thermal equilibrium in their cell cultures.

Other researchers believe the stress proteins are unrelated to thermal effects, since they occur for both extremely low frequencies (ELF) and radio frequencies (RF), which have very different energy levels. Another preliminary study published in 2011 byThe Journal of the American Medical Association conducted usingfluorodeoxyglucose injections andpositron emission tomographyconcluded that exposure toradiofrequency signal waves within parts of the brain closest to the cell phone antenna resulted in increased levels of glucose metabolism, but theclinical significance of this finding is unknown.

Blood–brain barrier effects

Swedish researchers from Lund University (Salford, Brun, Persson, Eberhardt, and Malmgren) have studied the effects of microwave radiation on the rat brain. They found a leakage of albumin into the brain via a permeated blood–brain barrier. This confirms earlier work on the blood–brain barrier by Allan Frey, Oscar and Hawkins, and Albert and Kerns. Other groups have not confirmed these findings in vitro cell studies or whole animal studies,

Prof Leszczynski of Finland's radiation and nuclear safety authority found that, at the maximum legal limit for mobile radiation, one protein in particular, HSP 27, was affected. HSP 27 played a critical role in the integrity of the blood-brain barrier.

Cancer

In 2006, a large Danish group's study about the connection between mobile phone use and cancer incidence was published. It followed over 420,000 Danish citizens for 20 years and showed no increased risk of cancer.A 2011 follow-up confirmed these findings.

The following studies of long time exposure have been published:

• The 13 nation INTERPHONE project – the largest study of its kind ever undertaken – was published in 2010 and did not find a solid link between mobile phones and brain tumours.

                     Thank You.