Jeff Gossett asked:
Recently read an article on effects of wifi on the brain, especially small children and while there seems to be a strong debate over the findings, I've become a bit concerned. Our 3 yr. old son Gus attends preschool where the admin. use wifi, so I have curtailed use of wifi in our home and hardwired the computer. Of most concern, if there need be, is that we are still inundated with a dozen other signals in our building. Care to take a whack at this one? Should we break out the aluminum foil hats? Great job, The Naked scientist is my go to podcast.
Thanks, Jeff in Spain
Hannah - There is a paper that was published in 2010 by Martin Bootman at the Babraham Institute in Cambridge and they looked at rat hippocampal neurons, which are primary neurons that are quite susceptible to external environments while getting their neural circuitry together...
Chris - These are brain cells.
Hannah - These are brain cells in a Petri dish and they exposed these brain cells in a Petri dish to 900 megahertz electromagnetic radiation for 30 minutes.
Chris - Dave, where does that sit in the spectrum of wavelengths? A microwave oven will be around 2 Ĺ gigahertz. That will be about 2 Ĺ times higher frequency than that. So where is 900 MHz?
Dave - 900 megahertz, is still in the microwave region, but itís at the bottom end of the microwave region. Some mobile phones work on that, others are a bit higher.
Chris - So itís in the right sort of ballpark. What did they find, Hannah?
Hannah - Well they looked specifically at calcium signalling in these nerve cells and they looked by labelling, using a fluorescent dye to tag to calcium activity. Calcium signalling is very important because itís involved in neurotransmission and enzyme activity, and brain inflammation processing and transfer.
Chris - So you use the calcium signal as an index of what the cells are doing, asking if we zap the cells with microwaves or not, if there's a difference?
Hannah - Exactly.
Chris - What did they find?
Hannah - They didnít find any difference at all. They had a look at the baseline calcium levels after 30 minutes of 900 megahertz and they found no effect, no significant effect on the calcium signalling. They also provoked a calcium response by adding in an agonist that caused a large calcium response and they found that the electromagnetic radiation had no effect on these cells in a Petri dish.
Chris - And obviously, weíre interpreting this within the constraints that this is a certain frequency, weíre exposed to many others. I mean, what do you think, Dave? Are you happy with that piece of research or would there be other questions you'd like to ask?
Dave - Itís not a kind of electromagnetic radiation which is likely to give you cancer directly. The wavelength from mobile phones is several centimetres so itís not going to interact strongly with anything which is a lot smaller than that. So, the only conceivable effect I could imagine would be some very large scale thing, but there hasnít been any big effect which people have noticed. People havenít suddenly all started keeling over and dying, so I'm not worried about it anyway.