Dr. Alice Stewart (again)

[BobCherry@aol.com]

FYI.

Bob Cherry
bobcherry@aol.com
=================================

   The survivor 

In the 1950s, Alice Stewart found that exposing pregnant mothers to X-rays 
doubled the risk of cancer in their children. Ever since, the physician and 
epidemiologist has argued that low doses of radiation might be harmful. It's 
a view that has put her at odds with governments, the military and the 
nuclear industry. This week, Stewart, who is 93, publishes new research 
supporting her claims. Michael Bond spoke to the maverick of radiation 
epidemiology and found her in fighting form 

What new evidence do you have to support your claims that low-level 
radiation 
could be dangerous? 

Radiation safety standards are derived from studies of the A-bomb survivors 
of Hiroshima and Nagasaki. These studies were food for people supporting 
hormesis, the theory that a little bit of radiation can be good for 
you--that 
it stimulates the immune system. When it was found that a small number of 
the 
A-bomb survivors were living longer than they ought to, this was seen as 
proof that radiation had done them good. But we have new data that should 
put 
paid to that. We have proof that the A-bomb data have been wrongly 
interpreted. (See "Radiation: how safe is safe?") 

What does your research show? 

It shows that cancer was not the only effect of the A-bomb radiation. People 
died from immune system damage as well. Our paper also shows that the A-bomb 
survivors were not a normal, homogenous population. They were the best 
athletes--the top 10 per cent--and did not include the young and the old. 
This means that we cannot base standards of radiation safety on such an 
elite 
cohort. 

Do you think that the authorities will now reassess the idea that radiation 
at low doses is not harmful? 

I think this new paper will do it. But I don't think it will lead to an 
immediate reaction. 

Why do you think your findings always take so long to be taken seriously? 
Take your work in the 1950s showing that a fetus exposed to X-rays has a 
higher risk of cancer. Or your findings in the 1970s that workers at the 
Hanford weapons complex in the US were getting cancer after supposedly safe 
levels of exposure. 

The trouble is that I've always had a very small set-up, with only just 
enough money to employ people to do the research. I've never had a 
department 
that's out selling the message to other people. So it's been a bit slower 
than usual. 

When it came to my work on X-rays, nobody wanted to believe it. X-rays were 
a 
favourite toy of the medical profession. But much more than that, it was 
just 
the moment when the nuclear industry was taking off. If we were right, the 
industry couldn't develop properly. 

Your work has tended to attract a lot of criticism from scientists, one of 
whom is the leading epidemiologist Richard Doll. Why do you think he doesn't 
like your work? 

I moved to Birmingham University for that reason. I knew that if I stayed at 
Oxford I would always be under the thumb of Doll. But that is the 
extraordinary thing. I can have reason to be angry with him because he was 
powerful and I was weak. He can have no reason at all to be angry at me, and 
yet he must resent me for some reason. Something irks him about me, and I'm 
conceited enough to think he suspects I'm a better epidemiologist than him. 
Now, he will tell you he has never had any quarrel with me at all. 

Doll has criticised your methodology on the Hanford Studies. Why? 

He's criticised my methodology from the word go. I don't know why. He's even 
criticised the mathematics of George Kneale, my statistician. But Doll 
doesn't know a fraction of the mathematics that George knows. I don't know 
what he means when he says our method is wrong, but he should be called to 
account. 

The main objections to my X-rays study was that the mothers were lay 
informants --that they weren't scientists, and they could have made up 
stories. We always knew there were weaknesses in our story. But we'd done 
our 
best to check this through the hospitals where they had their X-rays. 

You've been described as "an avowed opponent of the nuclear industry". Are 
you? 

Well, I've never avowed it to anybody. But if by the nuclear industry you 
mean the war and energy industries, then yes I'm against it. If you mean, do 
I think we should stop using X-rays, then no, but you must use them knowing 
they are a dangerous toy. I think the medical profession has quite a lot of 
uses for it. Take, for example, irradiated food. If this was going to 
prolong 
the life of food that you could send to a country to save it from starving, 
it would be excellent. But what you've got to be careful of is not to allow 
industry to indiscriminately use this radiation and to find it's going down 
your back drains. 

I'm automatically against it for war, and you have to remember that the 
nuclear military and energy industries have always been far more intimately 
connected than most people realise. 

The discovery that made your name in 1956 was that a fetus exposed to an 
X-ray is twice as likely to develop cancer within 10 years as one that is 
not. Did this finding come as a complete surprise to you? 

Yes. We weren't particularly looking for a link between cancer and X-rays. 
We 
were comparing the medical records of children who had died from leukaemia 
with those of healthy children from the same regions. And in the 
questionnaire, we had asked mothers if they'd been X-rayed. It looked to me 
as if there had been something before birth that produced a little epidemic 
at a certain age group that never repeated itself. But the risk was so small 
that if we'd tackled it any other way we'd never have discovered it. 

We were lucky, but it wouldn't have been thought of by someone who hadn't 
had 
some experience of medicine, and it might have been wrongly interpreted. 

So if you hadn't found the link it might have been another 20 years before 
someone else did? 

No, not 20 years. To this day we would be thinking X-rays were safe. This is 
because, as I've indicated, the A-bomb survivor studies from Hiroshima and 
Nagasaki, which was the only other study on this, was saying it was safe, 
and 
this would have been considered satisfactory to the point where everybody 
would have been quite happy about X-rays. 

How much do you think being a woman helped or hindered your career? When you 
first walked into the lecture hall as a medical student at Cambridge in 1925 
you were met with 200 male students stamping their feet at you. 

I'm sure my sex made a tremendous difference. But thanks to my family--my 
mother was a doctor--and thanks to the war, rather than being a crippling 
difficulty it actually proved to be rather a helpful one. I found I was 
constantly thinking of things in an unusual way. I didn't expect to be 
allowed to get to the top rung, which is something a man would expect, and 
so 
perhaps that made it easier to stay with a subject that wasn't very popular. 

Has that bothered you? 

Not at the time, but in retrospect I think it's the one thing I rather 
regret 
. . . that I should have pressed for something more. But I was stuck, I 
could 
only do one or other of two things: I could either be fighting the battle 
for 
women or I could be getting on with my job. I couldn't win both. And I chose 
to go on with my job. But I think a braver person might have done something 
about it. 

Were you ever bitter about being sidelined? 

No, I think I personally had everything to gain by it. It's always worked in 
my favour. An element of uncertainty is always a good thing. It's been a 
constant help. You need some resistance and criticism to bring out the good 
work. One of the reasons it's been so interesting for me is that no one has 
ever lost interest in what I've said about radiation. They may despise me, 
they may hate me, but the problem is there and will stay there if nobody's 
solved it. 

Most people think about cutting back on work when they reach seventy. Did 
you 
miss out on anything by carrying on in your nineties? 

I stayed working because I was enjoying it, and it was all voluntary. It 
became obvious early on that we had hit on something that was going to take 
more than a lifetime to resolve. It wasn't just the radiation thing that 
interested me. I was really interested in where the other cancers were 
coming 
from. You need to follow it for a long time. 

Who will carry on your fight in the radiation debate? 

I've got a voice in the next generation in Steve Wing and his department at 
the University of North Carolina at Chapel Hill. Mind you, they're going to 
make life difficult for them, with grants and everything. People in the 
nuclear industry will do their very best to stop it. But I'm a great 
believer 
that in the end, they'll get caught up in their own machinations and the 
truth will emerge from an unexpected quarter. 



Further reading: 

"A bomb survivors: factors that may lead to a re-assessment of the radiation 
hazard", International Journal of Epidemiology, volume 29, no 4 (4 August 
2000) 
The Woman Who Knew Too Much by Gayle Greene, University of Michigan Press, 
£19.99, ISBN 0472111078 



Radiation: how safe is safe? 

The A-bomb database--a record of the health and mortality of the survivors 
of 
the Hiroshima and Nagasaki atomic bombs--is considered the gold standard 
when 
assessing the health risks of radiation. Alice Stewart, however, has spent 
much of her career arguing that it cannot be trusted. Her latest research, 
published this week in the International Journal of Epidemiology (vol 29, no 
4), strengthens that argument. 

The database is used to compare the mortality rates of A-bomb survivors with 
other Japanese citizens born at the same time. The results have always been 
the same: people exposed to low doses do not have a higher than average risk 
of cancer. 

Stewart says these conclusions are unreliable because the bomb survivors are 
not truly representative of Japanese society. 

In her latest paper, she focuses on the 2600 people who suffered severe 
radiation injuries even though most received only a small radiation dose. In 
particular, she wanted to compare their incidence of cancers and other 
diseases with that of around 60 000 low-dose survivors who did not suffer 
from serious injuries. 

Stewart found the minority group had a much higher incidence of cancer and 
heart disease. She says these findings were reported to the European 
Parliament two years ago (see New Scientist, 28 February 1998, p 12) but 
that 
the assembly, curiously, decided not to make them public. 

Stewart's detractors have pointed to a series of studies showing that 
certain 
survivors of the Hiroshima and Nagasaki bombs lived slightly longer than 
people who had not been exposed. 

But research published in The Lancet (vol 356, p 303) at the end of last 
month casts doubt on these results. Researchers from the Radiation Effects 
Research Foundation in Hiroshima examined the effects of radiation on the 
120 
000 A-bomb survivors and found that people who received low doses did not 
live longer than average.