Breaking down radiation fears

SINGAPORE - The BioInitiative Report, first released in 2007, reappeared in a major update in January. The 1,479-page self-financed, self-published online document incorporates the 2007 version with new sections.

The updated report argues that there are indeed adverse health effects from electromagnetic fields (EMFs) at both the frequencies that mobile phones and Wi-Fi (wireless) transmit and also at the extremely low frequencies that powerlines transmit.

As power lines are buried underground in Singapore, the EMFs they radiate are very weak at ground level and so are of much less concern here.

The report claims that EMFs at their officially permitted levels today are linked to autism, neurological problems in children whose mothers used cellphones in pregnancy, Alzheimer's, cancer and so on. It manages to reach such conclusions by cherry-picking studies that support the thesis while ignoring those that don't.

Reviewing the 2007 report, the Health Council of the Netherlands concluded in 2008 that given its "selective use of scientific data and other shortcomings noted, it is not an objective and balanced... report (so it) does not provide any grounds for revising current views" about EMF risks.

The revised edition, a compilation of 24 main chapters written by 29 individuals about five years apart, is no different. Except for three of them, all writers have earned science doctorates or medical degrees but are also well known for their unconventional stand on EMF health effects.

The project organiser who co-authored the introduction and the conclusion is an activist without a science doctorate or medical degree: Mrs Cindy Sage, whose own firm consults on the hazards of EMF exposure, also contributed sections on how official EMF exposure limits are inadequate, so new standards a million times weaker than currently permitted under United States and international regulations were proposed.

But this is not a consensus of the chapter authors as one of them, Dr Henry Lai, emeritus professor of bioengineering at the University of Washington, has noted. Under these new standards, signals from cellphones, Wi-Fi devices, cellular base stations and other items would not be in compliance. Presumably, this might generate lots of consulting work assessing compliance for Sage EMF Design environmental consultants.

These claims are highly contested. When you get a call, Wi-Fi signals reach your phone - and your brain. But Wi-Fi signals carry very little energy, so they cannot break down the chemical bonds in DNA. It cannot cause mutations that lead to cancer. It has enough energy to only heat up water found in cells. Safety limits for Wi-Fi exposure are set to guard against such thermal damage.

However, in 2011, the World Health Organisation (WHO) announced that cellphones are "possibly carcinogenic to humans". It noted a possible link between cellphone use and glioma, a malignant brain cancer.

Perhaps Wi-Fi can somehow cause DNA to break down anyway? To postulate a possible mechanism for this, the report turns to an offbeat hypothesis from one of its authors, Dr Martin Blank, who retired as an associate professor at Columbia University's department of physiology and cellular biophysics in 2011.

It is recognised that thermal, chemical and other stresses are associated with a specific type of protein called "stress proteins". For any cell to make any protein, the DNA double helix must first be opened up to be read. Dr Blank thinks that the production of stress proteins in the presence of Wi-Fi implies that Wi-Fi can open up the DNA double helix.

He contends that DNA coiled up inside each cell nucleus acts like an antenna that picks up a range of frequencies, some of which may be able to open up DNA to be read. If DNA is misread, mutations may occur and some may cause cancer.

The Blank hypothesis remains unproven but is repeatedly cited as the mechanism by which weak Wi-Fi signals could damage DNA. A more conventional decade-long, 13-nation study called Interphone conducted under the WHO's auspices and published in 2010 concluded: "Overall, no increase in risk of glioma or meningioma (the most common types of brain tumour) was observed with use of mobile phones."

It did note an "increased risk of glioma at the highest exposure levels" of 30 minutes a day for 10 years but only in those who started cellphone use most recently, usually the young. This was the basis of the WHO's "possibly carcinogenic to humans" note.

As the US was not included in the Interphone study, its National Cancer Institute conducted its own study, which was published last year in the British Medical Journal. While cellphone use jumped from nearly zero to almost 100 per cent of the US population from 1992 to 2008, glioma incidence rates remained unchanged in all age groups. Thus, it found no link between cellphone use and gliomas.

Sceptical folks may argue that cellphone use rose only after 2000, say, so we need data up to 2020 to properly assess the risk with 20 years of exposure or more, as is usual for cancer studies.

We will also need better data. A critical flaw in most such studies is cellphone use being estimated through user recall, so recall bias creeps in. Telcos have precise usage data for each cellphone user. If such data becomes available - anonymised to obviate privacy concerns - then future studies may shed more light.

For now, the science doesn't suggest you drop that smartphone for a good old land line. Your current cellphone emits much less Wi-Fi than your old ones. But usage now is much heavier too. So just use it less.

andyho@sph.com.sg


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