Prof. Henshaw article says "electrical field more important"


15 March 2001

The London Times news report below does a good job in its interview of Professor Denis Henshaw, the Bristol University researcher who has effectively proved the power line hazard issue.

Note, that he focuses on the importance of the electrical component of the powerlines 'electromagnetic' emissions.  OVERWHELMINGLY (since EPRI in the U.S. first postulated that the magnetic field was to blame) other researchers on the EMF hazard matter have researched  primarily the "magnetic" field effects......

The two (electrical field and magnetic field) are separate and different  in their effect in the ELF frequency ranges!!  Thus, professor Henshaw's comments below on that aspect ... are of enormous

-------- Original Message --------
Subject: Required Reading!! Prof. Henshaw article (Royds)..
Date: Tue, 13 Mar 2001 06:09:07 -0600
From: Roy Beavers <>
Organization: EMF-L List
To: undisclosed-recipients:;

........From EMF-L.......

If you have been reading the EMF-L traffic over the past 2-3 years, you are already well informed about the following.....  But look!!

It is being treated as if the British were just now becoming aware!!

-------- Original Message --------
Subject: Prof. Henshaw article
Date: Tue, 13 Mar 2001 06:15:26 -0000
From: "John Royds" <>
To: <>
References: <>


There was an excellent article in yesterday's (12th March) UK Times about Prof. Denis Henshaw and powerlines,,74-97331,00.html

I have pasted the article below.


John Royds
Timmore House
Co. Wicklow
Republic of Ireland
tel/fax:  +353-1-281 9283

The Times (UK)


Live and extremely dangerous

A study last week linked power lines to leukaemia. Physicist Denis Henshaw says they also cause skin cancer, lung cancer, depression and 60 suicides a year. Interview by Anjana Ahuja

Knowing what he knows, Denis Henshaw says he would never live in a house near overhead power lines. A physics professor at Bristol University, he has been studying the health effects of power lines since 1994. Last week, one of the issues he has championed for years - the link between childhood leukaemia and power lines - finally came out into the open. The National Radiological Protection Board (NRPB) concluded that exposure to magnetic fields may double the chances of a child developing the disease.

While welcoming the report, Henshaw says that the focus on childhood leukaemia, which is extremely rare, is a smokescreen that has served to conceal the real perils of power lines.

He estimates that power lines notch up the following grim tally each year: eight cases of childhood leukaemia, 14 cases of skin cancer, up to 400 cases of lung cancer, several thousand cases of illnesses associated with air pollution (such as respiratory disease, allergies and aggravated asthma), 9,000 cases of depression and 60 suicides.

The vast majority of these cases, he says, are caused by electrical effects, not by the magnetic fields that were under investigation by the NRPB. "These are figures comparable to the number killed on roads," says Henshaw, 54, whose smart appearance makes him look more like a company executive than a heretical professor. "But road deaths are spread throughout the country, while only one in 50 of the population lives under power lines. So the rate of casualty here is 50 times greater than the risks of being on the road."

He wants to see planning laws frozen so that no more homes are built near power lines, and new cables are strung up as far as practicable from populated areas or, where possible, buried.

He argues that although there may be no absolute causal proof yet, the correlations are so strong and the biological mechanisms so plausible that there should be a programme of "prudent avoidance". He says: "To say we need another ten years of research means we will go precisely down the BSE  route."

The Department of Health is listening - its officials have met him and seen his experiments - but his views have largely been ignored or rubbished. The electricity industry has accused him of scaremongering. He is not bothered: "People who accuse you of scaremongering are those who don't want the truth to come out. The utility companies can never admit in public that there is an effect, because that would be admitting liability."

But he is bothered by the personal abuse sometimes levelled at him. It is easy to compare him to Richard Lacey, the scientist who foresaw that BSE could infect human beings, and to Sir Richard Doll, who first posited the link between smoking and lung cancer, which was decried for decades by tobacco companies. "It's exactly the same problem," he agrees.

"He (Doll) was described as a young upstart and suffered other terms of abuse not terribly different from those used against us. The industry has written stinking letters about me, but thankfully the university has stood by me. I have been libelled on a number of occasions. We have had to remind people that we will take action against them."

The NRPB has offended him three times; on each occasion he has received an apology. He will not be pressed on the precise nature of the abuse, but says that the NRPB once claimed that his assessments of risk were coloured by the need to win research funds. He adds, somewhat indignantly, that his funds from the Medical Research Council and the Department of Health have been won through the normal process of academic assessment. The Foundation for Children with Leukaemia has also supported his work.

Ironically, the latest NRPB report suggests that Henshaw's work is worth further investigation. Yet the organisation has never consulted him personally on power lines and health, which he finds "extraordinary"." Dr Michael Clark, from the NRPB, says: "Professor Henshaw is a perfectly reputable scientist who has an interesting and plausible hypothesis. But it is a long way from that to a demonstrable health effect."

The dominant effect of the magnetic field, Henshaw says, is in influencing mood. His survey of existing data leads him to the figure of 60 suicides a year, as well as thousands of cases of depression. "There have been papers on this for 20 years," he says. "What strikes me is that they all show positive correlations and are not conflicting in any way. This is considered biologically plausible - one mechanism is that magnetic fields disrupt the production of melatonin in the body, which regulates mood. Another is that magnetic fields induce electrical currents in the brain, which create an electrical imbalance.

"Melatonin is produced by the pineal gland at night. Populations living near these things are obviously sleeping near them, and they show striking effects. Utility company workers show lower effects but they are exposed during the daytime, so that's what you would expect."

He rejects the popular claim that people who live near power lines are depressed for other reasons, perhaps because they simply don't like living near them, or because they tend to belong to lower income groups.

But Henshaw and his colleague, Dr Peter Fews, say that the gravest physical health problems stem from the electrical fields bathing power lines. In 1996 they reported that cables from domestic appliances, such as hairdryers, acted like magnets for radioactive substances. These substances were formed by the natural decay of radon in the atmosphere into so-called radioactive "daughters". The implication was that radioactive products were attracted to oscillating electrical fields. "Nobody seemed to spot the importance of that," says Henshaw.

"The importance is that these substances, which are known carcinogens, can land on you. When you stand under a power line, the electrical field distorts around you because you are a conductor. These pollutants are oscillating back and forth around you at 50Hz and they can land on you. Applying the NRPB's own risk factors, you can predict an increase in skin cancer."

He found that if a person spent 10 per cent of his time close to power lines, he would be subjected to up to twice the acceptable level of radioactivity, even in windy and wet weather. "Critics said that people don' t spend 10 per cent of their time near power lines, but my argument is that if they live there, they're entitled to," says Henshaw.

However, radon daughters pale into insignificance next to another set of villains named by Henshaw - corona ions. High-voltage power lines produce a strong electrical field on the line itself. This field is big enough to ionise the air around it - in other words, to strip electrons from atoms.

The effect is like nudging a line of dominoes: the ionisation of one atom triggers the ionisation of another, leading to a chain reaction. The result is a line of charged, highly reactive particles streaming away from the power cable. Henshaw has measured the streams as far away as several kilometres from the line.

These charged particles, or corona ions, act as magnets for air pollutants, including carcinogens such as aromatic hydrocarbons from car exhausts. The electric charge gives the pollutant, when inhaled, a greater ability to stick to the lung - so rather than being exhaled, pollutants become lodged. "New York scientists have found that if there is a charge, pollutants of this size are two or three times more likely to be deposited in the lungs," he says. "In the confined space of the lungs and airways, this charge makes a big difference.

"The upshot is that you are retaining air pollutants, some of which are known to be linked to lung cancer, in your lungs. You can then do a rigorous assessment for lung cancer, which I put at between 250 and 400 cases a year. There is actually a paper - not mine - that shows a doubling of lung cancer under power lines, but it hasn't been talked about."

When the other effects of air pollutants, such as allergies and respiratory disease, are factored in, Henshaw estimates that corona ions probably damage a few thousand people every year. He also points out that corona ions have been known about since the Fifties, and have been studied extensively by the industry.

His final analysis is simply this: there is a vast body of evidence to indicate an association between power lines and ill-health. It includes cancers and non-cancers, affects both adults and children, and the risk of ill-health is high enough to justify immediate action. This does not mean that people living near power lines should panic - the risk of death on the roads does not panic car-owners into selling their vehicles. Likewise, even if several thousand people are at risk from power lines, the probability of an individual falling ill is small.

However, given the response to BSE and the rail tragedies, the refusal to acknowledge that there is a problem or to act on these statistics confounds Henshaw. "I am struck by what society accepts," he says. "The Paddington rail crash killed 31 and triggered a £1 billion commitment to advanced train protection. Governments have to respond to risk assessment, not hide behind wanting strict causal proof. Risk assessment grounded the whole Concorde fleet. I'm saying that this is comparable.

"A hundred years from now, we will look back at pylons as relics of the mid-20th century. It probably won't happen in five or ten years, but eventua lly a new generation will come along, change things, and wonder why we did nothing."

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