Alice queries science's wonderland

The devastation of Hiroshima and Nagasaki in 1945 was plain to see, but the true horrors of radiation damage to thousands of survivors were concealed by the nuclear establishment and self-deluding politicians. Worse, their gross underestimates became benchmarks for radiation hazards. One of the courageous few to challenge the establishment view, from the 1970s, was the epidemiologist Alice Stewart, the maverick subject of this biography. She uncovered the true hazards of X-raying pregnant women, linking them to childhood leukaemia and cancer, and in all her research she challenged accepted safety standards.

Her story is well worth telling, not least because it is insufficiently known. Like her mother, she was a pioneer doctor. She qualified in a female medical school then led an enviable intellectual life at Cambridge in the 1920s. She heard Virginia Woolf's talk to the "One Damn Thing after Another" Society that later became A Room of One's Own .

Although William Empson was Stewart's first and last love, she married Ludovick Stewart. His appointment to Harrow School in London helped her career. She became a registrar at the Royal Free Hospital, sharpening her diagnostic skills, and a consultant at the Garrett Anderson Hospital in 1939, evacuating to St Albans during the war. The Stewarts' careers diverged when Ludovick went to Bletchley Park and Alice moved into social medicine at the Nuffield Hospital in Oxford. "The war enabled me to leap over barriers that would otherwise have blocked my way as a woman," she says.

Stewart was elected fellow of the Royal College of Physicians in 1946 - the ninth female fellow, and the first under 40. She was co-founder of the British Journal of Industrial Medicine .

It was in Oxford that she studied the health risks of industrial chemicals in factories doing war work. With 40 undergraduate volunteers filling shells with TNT, she showed the risks of anaemia and liver disease to be dose-related.

She studied pneumoconiosis among coal miners in Wales, working with their communist leader, Arthur Horner. Risks were downplayed. The deaths of miners at 55 were recorded as "succumbed to old age". A miner who died of drink at 82, she reckoned, was an excellent advertisement for drink. As ever, she battled against the established view.

In 1943, appalled by disparities in infant mortality between the rich and poor, John Ryle founded an Institute of Social Medicine in Oxford and appointed Stewart as his assistant. After Ryle died in 1950, Stewart was made head of a social medicine unit as a reader, and fellow of Lady Margaret Hall. With no resources she raised money to hire an assistant and a statistician, systematised the records and studied leukaemia. The Oxford Survey that Stewart produced was rich in detail, which, with her insight, uncovered vital correlations. For example, she found that exposure of either parent to ionising radiation correlated with childhood leukaemia, often recorded as cot death. She fought to establish that there is no "safe" or threshold dose of radiation. Nowadays we recognise the hazards to cells in division, and therefore to the foetus - a single hit can cause mutation. X-raying of pregnant women was discontinued and X-ray viewers disappeared from shoe shops.

Stewart left Oxford in 1974 and, along with George Kneale, her statistician, took the Oxford Survey to the University of Birmingham, which later made her a professor.

Invited to the United States in the 1970s, she observed workers in the nuclear weapons industry at Hanford and Oak Ridge dying of radiation-induced cancers. Safety standards, though better than elsewhere, were too low. High exposures were concealed, injury was disputed, compensation was mean and whistleblowers were blacklisted. Stewart noted subtle factors, such as the survival of the healthiest workers, even though they were put in higher-risk occupations, which pointed to a genetic link. When she was 80, she was awarded $2 million (Pounds 1.3 million) to study the records of nuclear workers from the US weapons complex.

Her evidence of the hazards of parental exposure to radiation around nuclear installations is still disputed. She showed supposedly "safe" levels to be too high, but lowering them would open the floodgates to claims. A 1982 study by the National Cancer Institute, commissioned by Congress, estimated that in the west of the US, people received doses of radio-iodine in atom-bomb fallout that were 100 times greater than those estimated in 1959, ten times greater than at Chernobyl, leading perhaps to 10-75,000 thyroid cancers, most as yet undiagnosed.

Stewart's 1970 Lancet article on "Gene-selection theory of cancer causation" quotes from an Empson poem: "How small a chink lets in so dire a foe." Slowly international researchers are demolishing what she calls "the gold standard": the long-standing, meretricious interpretation of the Hiroshima data. "Truth is the daughter of time," she says.

Gayle Greene's biography is well referenced, while betraying its American origin. It tells a good story, much of it in its subject's own spirited words. Photographs show Stewart's family and friends, and her progress from charming young woman to lively, indomitable 90-plus year old. Nuclear weaponry has done more damage than Hiroshima, Nagasaki and nuclear testing. The killing of Lumumba, support of Mobutu and Kabila, and much of the subsequent tragedy of sub-Saharan Africa can be traced to "safeguarding" Congolese uranium. What will Sellafield do with its 60 tonnes of plutonium (half-life 24 millennia)? The Barents Sea, rich in fish, is described as "Chernobyl in slow motion" - what are those nuclear submarines doing? We need more whistleblowers like Alice Stewart.

Joan Mason is senior affiliated research scholar, department of history and philosophy of science, University of Cambridge.