CCD and electromagnetic radiation
As I was saying, I’m not so sure that electromagnetic radiation should be so easily dismissed as a possible cause of colony collapse disorder (CCD).
There is clear evidence (see Hsu et al and the references therein) that electromagnetic fields can impact both the behavior and the navigational abilities of honeybees. As I started to explain, with the emergence of Wi-Fi and coming WiMax, the thing that is different now compared to the past 10-15 years is the frequencies involved with our wireless devices. Part of my MS thesis research (Go Illini!) involved simulating the EM radiation from a cell phone through a 1 cubic mm voxel resolution model of a human head taken from MRI data.
I was not involved with any medical research. Rather, we were looking at it from a purely engineering perspective, e.g. how does the human head impact the performance of the antenna, etc. Nonetheless, I would get questions after each presentation about whether I thought cell phones were safe. At the time, cell phones were operating at 900 MHz. At these frequencies, the wavelength of the radiowave is a little over 30 cm (~1 foot). The length of the wave is important due to the phenomenon of resonance (as in the Tacoma bridge). Radiowaves tend to interact more strongly with objects that are roughly the same size as the wave (or integer multiples thereof). In the human body, roughly speaking, the length of the wave is about half of its length in air. At 900 MHz, this means that the length of the wave in the body is roughly 6 inches. Therefore, even at low power, there is a remote chance that the wave can begin to resonate strongly with organs that are 6 inches in diameter. The brain? Maybe. I dunno. I’m not a doctor 🙂
The point is that I was fairly certain that 900 MHz radiation did not pose a health risk and that was the story I stuck to whenever anyone would ask. But 1900 MHz? 2500 MHz? Anything above 1000 MHz (or 1 GHz) is beyond my comfort zone. At 1900 MHz, the length of the wave in the body is a little over 3 inches. The size of an eyeball maybe? Now I’m getting a little uncomfortable. At 2500 MHz (the frequency at which Wi-Fi and Wimax operate… not to mention microwave ovens), the length of the wave in the body is a little over 2 inches. Hmm…
Are we sure we want to be radiating ourselves with the exact same radiation frequency that is used in microwave ovens (whose very operating principle is based upon resonance with water molecules)? That is not a rhetorical question. I would really like to know the answer and don’t. What I do know is that there has not been enough research at these frequencies (unlike at the lower/older cell phone frequencies) to say with certainty either way. At high enough power, microwave radiation is certainly known to cause cataracts in the human eye and that was one of the first papers I read in computational electromagnetics. Is it really so outrageous to think that microwaves could throw a honeybee off course?
So it is not so unlikely that some kind of electromagnetic resonance could be causing CCD. The papers referred to in the link above make it clear that honeybees are sensitive to electromagnetic fields and if that is the case, then resonance could be a culprit.
I was even more convinced about the possibility of a link between CCD and electromagnetic radiation when I learned (via blogs, so it may not be totally accurate) that only genetically altered honeybees were being affected. These affected bees were roughly twice the size of the unaltered bees who were not impacted. Resonance. Resonance is very sensitive to the size and shape of the object the radiowaves are interacting with.
Radiowaves possess a beautiful symmetry called “conformal symmetry”. Roughly, what the means is that as far as radiowaves are concerned, doubling the size of something is equivalent to doubling the frequency of the radiowaves it interacts with. So what one honeybee experiences at 2.5 GHz will be the same as what another honeybee half the size will experience 5 GHz!
It is the size and shape of the honeybee that determines how strongly it will interact with radiowaves at different frequencies and I’m a little disappointed not to see more people (except maybe in Taiwan) taking the possibility seriously.
Edit: I forgot to mention that one of the reasons for me to write these last two articles at this time (I planned to write about it eventually anyway) was the announcement yesterday that the USDA is launching a research action plan to look into CCD. They listed four possible causes of CCD they plan to pursue:
- New or reemerging pathogens,
- New bee pests or parasites,
- Environmental and/or nutritional stress, or
Radiowaves MIGHT be included in “environmental”, but it seems not very likely that it is a central focus (which I think it should be).