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Mobile phones alter cells without heating them
This week– trigger for the enzyme is the release of reactive oxygen species in the cell membrane (Biochemical Journal, DOI: 10.1042/ BJ20061653). The team is confident that the effect was not caused by heating: “The radiation that we used was
“There had been no clear mechanism by which cellphone radiation and power levels could harm living cells” very low-energy, and our sensitive thermostats did not register a change in the temperature of the cell medium,” says team member Rony Seger. “The significance lies in showing that cells do react to cellphone radiation in a nonthermal way.” While mutations in ERK pathways have been linked to –Cellphone radiation is a subtle customer– several cancers, experts caution that this is not necessarily evidence of a cancer-causing effect. “Transient and reversible activation such as this is unlikely to [cause cancer],” says Simon Arthur at the University of Dundee in the UK. In fact, he says, “transient activation of ERK1/2 occurs frequently in response to a huge variety of signals and is an evidence of non-thermal effects essential component of many on cells is mixed, because it is aspects of cellular physiology”. very difficult to expose cells to Dariusz Leszczynski of the radiation without heating them Radiation and Nuclear Safety to some degree. Authority in Helsinki, Finland, In the new study, Joseph also cautions against making the Friedman and colleagues at the leap between cells and health Weizmann Institute of Science in effects, but says they cannot be Rehovot exposed rat and human ruled out. “If cellphone radiation cell cultures, and also isolated cannot induce biological effects cell membranes, to low-level then there will never be any electromagnetic radiation at health effects,” he says. “On the 875 megahertz – a similar frequency to those of GSM phone other hand, if we can show that this radiation is able to induce signals. The power of the signal biological effects then we have was far lower than the intensity a different story. It doesn’t of the typical cellphone, yet after automatically mean that it will be just 10 minutes of exposure, harmful, but we will need to study the team identified activation it further.” of the pathway for ERK1/2, an In 2002, Leszczynski enzyme that regulates cell reported that cellphone radiation differentiation and division. stimulated a stress-related The researchers then inhibited pathway downstream of ERK1/2, various stages in the pathway but did not investigate what could upstream of ERK1/2 and be triggering it. ● concluded that the molecular
Can ‘cold calls’ affect your brain? CAROLINE WILLIAMS
CELLPHONE makers take great care to ensure their gadgets don’t heat up your brain, but could the radiation cellphones throw out damage your cells in some other way? Israeli researchers have now identified a mechanism through which the radiation may affect the differentiation and division of cells. Claims of connections between cellphone radiation exposure and health problems such as cancer have been controversial, largely due to a lack of convincing evidence, but also because no clear mechanism was known by which radiation at cellphone frequencies and power levels could harm living cells. The frequencies are too low to damage DNA directly and the power of the signal is well below the level that could overheat cells. Previous 18 | NewScientist | 1 September 2007
THIS WEEK 50 YEARS AGO Arms race goes ballistic Trials of new Russian long-range rockets began in late summer. Soviet scientists seem to have learned enough about the unpredictable behaviour of these weapons to control them, and they are now forming the prototype for the first intercontinental ballistic missiles, accurate to within about 12 miles. Meanwhile, the US long-range weapons programme revolves around the 5000-mile-range Atlas missile. One was first fired a few weeks ago but had to be destroyed when it strayed off course. The Russian announcement therefore puts the Soviet Union a short neck ahead of the US in the race to develop weapons capable of reaching into the heart of each other’s territory. Previously, only strategic long-range nuclear bombers could reach opposition airspace, but some form of ground-to-air defence against these planes was always possible. Missile warheads, however, arrive at 20 times the speed of sound, or about 15,000 miles per hour, and so are obviously far more difficult to halt than relatively slow-moving aeroplanes. So the emphasis is now switching to defensive missiles capable of intercepting these ballistic monsters at the peak of their flight, when they are between 600 and 800 miles above the Earth and flying relatively slowly. The US is developing two types of antimissile missile as well as long-range radar that might extend the present warning radius from hundreds to thousands of miles, so giving the defence system a margin of up to 15 minutes in which to go into action. Ballistic weapons create so much disturbance in the atmosphere during flight that they present a reasonably trackable target, but even so, the time and effort it will to take to design a defence system fast enough to catch them is probably going to be even greater than that which has gone into the development of the ballistic missiles themselves. From The New Scientist, 5 September 1957
www.newscientist.com
“There had been no clear mechanism by which cellphone radiation and power levels could harm living cells” very low-energy, and our sensitive thermostats did not register a change in the temperature of the cell medium,” says team member Rony Seger. “The significance lies in showing that cells do react to cellphone radiation in a nonthermal way.” While mutations in ERK pathways have been linked to –Cellphone radiation is a subtle customer– several cancers, experts caution that this is not necessarily evidence of a cancer-causing effect. “Transient and reversible activation such as this is unlikely to [cause cancer],” says Simon Arthur at the University of Dundee in the UK. In fact, he says, “transient activation of ERK1/2 occurs frequently in response to a huge variety of signals and is an evidence of non-thermal effects essential component of many on cells is mixed, because it is aspects of cellular physiology”. very difficult to expose cells to Dariusz Leszczynski of the radiation without heating them Radiation and Nuclear Safety to some degree. Authority in Helsinki, Finland, In the new study, Joseph also cautions against making the Friedman and colleagues at the leap between cells and health Weizmann Institute of Science in effects, but says they cannot be Rehovot exposed rat and human ruled out. “If cellphone radiation cell cultures, and also isolated cannot induce biological effects cell membranes, to low-level then there will never be any electromagnetic radiation at health effects,” he says. “On the 875 megahertz – a similar frequency to those of GSM phone other hand, if we can show that this radiation is able to induce signals. The power of the signal biological effects then we have was far lower than the intensity a different story. It doesn’t of the typical cellphone, yet after automatically mean that it will be just 10 minutes of exposure, harmful, but we will need to study the team identified activation it further.” of the pathway for ERK1/2, an In 2002, Leszczynski enzyme that regulates cell reported that cellphone radiation differentiation and division. stimulated a stress-related The researchers then inhibited pathway downstream of ERK1/2, various stages in the pathway but did not investigate what could upstream of ERK1/2 and be triggering it. ● concluded that the molecular
Can ‘cold calls’ affect your brain? CAROLINE WILLIAMS
CELLPHONE makers take great care to ensure their gadgets don’t heat up your brain, but could the radiation cellphones throw out damage your cells in some other way? Israeli researchers have now identified a mechanism through which the radiation may affect the differentiation and division of cells. Claims of connections between cellphone radiation exposure and health problems such as cancer have been controversial, largely due to a lack of convincing evidence, but also because no clear mechanism was known by which radiation at cellphone frequencies and power levels could harm living cells. The frequencies are too low to damage DNA directly and the power of the signal is well below the level that could overheat cells. Previous 18 | NewScientist | 1 September 2007
THIS WEEK 50 YEARS AGO Arms race goes ballistic Trials of new Russian long-range rockets began in late summer. Soviet scientists seem to have learned enough about the unpredictable behaviour of these weapons to control them, and they are now forming the prototype for the first intercontinental ballistic missiles, accurate to within about 12 miles. Meanwhile, the US long-range weapons programme revolves around the 5000-mile-range Atlas missile. One was first fired a few weeks ago but had to be destroyed when it strayed off course. The Russian announcement therefore puts the Soviet Union a short neck ahead of the US in the race to develop weapons capable of reaching into the heart of each other’s territory. Previously, only strategic long-range nuclear bombers could reach opposition airspace, but some form of ground-to-air defence against these planes was always possible. Missile warheads, however, arrive at 20 times the speed of sound, or about 15,000 miles per hour, and so are obviously far more difficult to halt than relatively slow-moving aeroplanes. So the emphasis is now switching to defensive missiles capable of intercepting these ballistic monsters at the peak of their flight, when they are between 600 and 800 miles above the Earth and flying relatively slowly. The US is developing two types of antimissile missile as well as long-range radar that might extend the present warning radius from hundreds to thousands of miles, so giving the defence system a margin of up to 15 minutes in which to go into action. Ballistic weapons create so much disturbance in the atmosphere during flight that they present a reasonably trackable target, but even so, the time and effort it will to take to design a defence system fast enough to catch them is probably going to be even greater than that which has gone into the development of the ballistic missiles themselves. From The New Scientist, 5 September 1957
www.newscientist.com