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RF is killing bees!

I found this article and video interesting:  Study links bee decline to cell phones.

The article goes on about CCD (Colony Collapse Disorder) where entire bee colonies die off for unknown reasons.  Some speculate that increased use of pesticides might be to blame (makes perfect sense to me).  Still others think that cell phone towers are the culprits.  Noting:

“Animals, including insects, use cryptochrome for navigation,” Goldsworthy told CNN.

“They use it to sense the direction of the earth’s magnetic field and their ability to do this is compromised by radiation from [cell] phones and their base stations. So basically bees do not find their way back to the hive.”

One study in India involved attaching a cell phone to the side of a bee hive and powering it on for two fifteen minute periods each day. These researchers found that the honey production in the hive dropped off and the hive queen’s egg laying was cut in half.

All of that is indeed interesting, but somehow I think that a lot of information is lacking.  First of all, any first year physics student can tell you, the RF field around a cellphone antenna decreases logarithmically as a function of distance.  In other words,  for each unit of distance away from the antenna, the power density decreases by 10 times.  Therefore, placing even a mobile phone directly on a bee hive will likely generate much higher RF fields than would otherwise be encountered, unless there was a bee hive in one of the cell tower antennas.

Secondly, there is no mention of power levels, although the frequency appears to be in the 900 MHz range, if this is the study (.pdf) being referred to in the article.

Finally, the compound referred to, cryptochrome, is also interesting.  Breaking the word down, one finds “Crypto” which means hidden, and “Chrome” which means color.  According to the Wikipedia article, which most often can be believed when it comes to such subjects, it is indeed used by some animals to detect magnetic fields.  However, RF used by cell phones has long been in use by other technologies such as two way radio, pagers, cordless phones, baby monitors, TV, early radar and other high power emitters.  It would be most unusual that RF induced CCD would just now be showing up.

In short, there is very very thin evidence that cell phone are causing CCD and it is a shame on CNN for propagating such non-sense without doing research.

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3 comments to RF is killing bees!

  • Gary

    A minor (repeat – minor) quibble: your power density statement (10 times drop with each unit of distance) is a bit confusing. I prefer to say either that the *electrical field* drops off linearly with distance (ie every doubling of distance drops the electrical field by 1/2) -OR- the power density drops off as a square of the distance (ie every doubling of distance means the power density drops off by a factor of 4). But I agree with your statement. Thin. Further, making a few quick assumptions of a 900 MHz transmitter and an antenna ~10 cm long (runs the length of the phone), the far field is ~2 inches. Which means that the bees are being hit with a far higher magnetic field (which predominates in the near field) than they would by cell phone towers and other RF transmitters that are a long way off. This study only looked at *one* frequency and *one* power level. Plus, they only used GSM phones. Did their simple power meter accurately report the average power from a pulsed transmitter such as a GSM phone? And was the phone frequency-hopping? And was the beehive activity enough to activate the VOX in the phone mike? And is the average power important, or is it the peak power? In short, sounds as if they know a lot about bees, but diddly about RF or cellphones.

  • admin

    Hey Gary, I was going for power density, which is how tissue heating from RF is determined. If I remember my physics 101 correctly, that is a log function. The premise I was using was the “exponential decrease” as one program director put it, where, if a station was transmitting with 100 watts and wanted to double the coverage distance from the tower, they would need to increase to 1000 watts, a factor of 10. The coverage area would be increased by a factor of 4, as you noted.

    Anyway, as we both agree, the so called story and the study it is based on is full of technical errors.

  • Chuk Gleason

    Interesting bit of sensationalist quackery, to blame bee decline on cellphone radiation. But there has been much talk in the apiary community about the sensitivity of bee colonies to the herbicide Roundup. This is a subject which has been getting better reporting exposure now than when this ‘study’ came out in 2010.

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