Professor Al Rowland won't go into the politics of the matter. That's not his role, he says, though he admits he was elated for nuclear test veterans when they won the right to sue the British Ministry of Defence.

But he does repeat a remark from last month: "I said it's time for the politicians to put politics to one side and just acknowledge that something dreadful has happened to these men."

So though he is not a political beast, the recently retired scientist has much to be proud of.

It was Rowland's work on chromosome damage, described as pivotal by a British High Court judge , which tipped the decision to finally give former servicemen the go-ahead to seek compensation for radiation exposure from Operation Grapple, the nuclear bomb tests in the Pacific in the 1950s.

The troops, from Britain, Australia, New Zealand and Fiji, witnessed the explosions and sailed through the aftermath. At the time, some of the navy personnel were as young as 15.

They believe death, illness and psychological trauma have trailed them since.

Among the sailors were 551 New Zealanders on board the frigates Pukaki and Rotoiti. The vessels were used as weather ships during the tests and were sent with the consent of the New Zealand Government.

Professor Rowland is playing Bach when we call. Trained as a concert pianist, the 63-year-old spends most of his afternoons at the piano.

The Bach is tricky, he says, but he has learnt the piece and is at the polishing stage. He will put on a private recital for friends soon.

He agrees there just might be some correlation between the brains of scientists and musicians. "When you go to concerts and things in Palmerston North there's a lot of scientists who go along..."

As a youngster he had to make a choice which route in life he would take. Science won.

"I didn't have the temperament to become a concert pianist. On stage I used to fall apart, go to pieces and shake and quiver so I concentrated on the science."

Rowland is unfailingly polite, kindly and patient when explaining complicated science.

It's easy to see why, in 2008, the year before he retired, students voted him lecturer of the year at Massey University's Institute of Molecular BioSciences in Palmerston North.

He was inspirational, the students said, and always willing to help and encourage them.

When I describe the British Court decision as a victory, he says, well, that's very kind of you.

And he points out that though he found significant chromosome damage in the blood of New Zealand nuclear test veterans, it is up to others to decide on the cause.

Rowland drifts back in time to the early 2000s.

He had met with Roy Sefton, chair of the New Zealand Nuclear Test Veterans Association. Sefton's group had funding to prepare a legal claim against the British Government and for a study to see if there was genetic damage in veterans.

The investigation was to be conducted by British scientists but they couldn't get ethics approval.

Sefton asked Rowland if he would like to do it.

Rowland said he would have to think about it. The bomb blasts were 50 years ago and he wasn't sure there would be anything to find.

But the science would be fascinating. There were new tests, especially one which looked at translocations between different chromosomes - the swapping of genetic material.

Translocations show evidence of genetic damage and there's a strong link between them and cancer.

Before he took the project on Rowland talked to Massey colleague John Podd, a neuropsychologist with experience on the study of human populations.

Podd told him: "Look, you can't just go out and take the blood of the veterans. You have to design the study methodically and you must have matched controls."

Such a study would succeed or fail depending on how well the control group was selected.

They decided to give it a go. Says Rowland: "The alternative would be to do nothing and I thought that's not a good enough reason."

Rowland's team sorted out which tests or assays to use and Podd figured out how to select the veterans and the control subjects.

Selecting participants took ages. It was almost like a military exercise in itself, Rowland says.

"If the veterans were smokers, we had to have controls who smoked the same amount and if they drank alcohol the controls had to drink the same amount."

Participants were interviewed individually. A 64-page questionnaire detailed their medical background, lifestyle and work history. They wanted military men as the controls, and roughly the same age.

They had to select the same number of people from the same area.

"For instance, if a veteran lived in Kaitaia we hired a plane to fly [there] to interview the veterans and the prospective controls, just in case there was something odd about living in Kaitaia.

"Mortality rates around the country vary enormously and we had to be very careful in case there was some other confounding factor about living somewhere."

They had enough money to study 50 veterans, which meant they needed 50 controls, but Rowland says by the time they had set their strict inclusion criteria they were struggling to get 50 veterans, because many were ill.

Podd's group ran a parallel study on psychological impact, collecting data on state of health in the controls and the veterans and reported a whole range of illnesses.

Two significant differences stood out between the groups - the veterans had far more cancers and skin problems. They were also more depressed.

In the end, the results were stunning. The level of translocations in veterans was three times as high as in the control group.

How did Rowland feel about this?

"Oh, well, it was pretty scary. We knew that this was going to be politically very hot..."

And hot it has been.

* * *

Roy Sefton is happy to talk politics.

The 71-year-old, who suffers from muscle and skeletal pain, has been a tireless campaigner to get justice for nuclear test veterans.

Despite the big win in Britain, and as Australian veterans plan a class action against the Australian Government, the New Zealand veterans are considering seeking compensation from ours.

Sefton says this has been on their minds since a precedent of compensation to military personnel was achieved through the Vietnam War veterans a few years back with the decision to compensate some of those affected by Agent Orange.

And the British court decision gives Rowland's study much needed clout.

There have been so many delays already in getting to court, while veterans die, and the British Ministry of Defence has sought and won the right to appeal, which if they do will take further years veterans don't have.

Sefton says if a satisfactory settlement of compensation for a satisfactory range of health conditions could be obtained from the New Zealand Government, in a reasonably quick time, that would be a nice, tidy outcome.

But even this is complicated.

With some of New Zealand's Operation Grapple veterans - and their widows - connected by an agreement with the UK veterans' legal team, there may still be legal and political difficulties to overcome, Sefton says.

And why should the Kiwi veterans get compensation from the New Zealand Government when they have a chance to achieve a payout from the United Kingdom?

Because of negligence and a denial of human rights, says Sefton.

New Zealanders were sent as part of an experiment and back then a decision was made not to perform blood checks on naval servicemen, so that in the future it might have been hard for authorities in the UK to deny certain conditions were caused through their Grapple service.

"I consider," says Sefton, "that some of the recorded actions of the UK and their irresponsible radiation and service practices applying to the servicemen is on a par with the use of gas in World War I."

He says that Britain may have withheld a lot of information from the New Zealand Government at the time of the testing, but there was still enough concern to have withdrawn the Kiwis from the testing programme.

"Further ignorance offers no excuse for any New Zealand Government then and since," he says.

Human experimentation, says Sefton, is perhaps the lowest act that can be enacted on fellow human beings.

"Worst still when those performing the experiment are, in fact, your own people."

Sefton is at an age where he should be winding down and relaxing. No chance, he says.

" I've got the tiger by the tail."

An Expert Panel on Veterans' Health has been set up and tasked with looking at research into the health effects of New Zealand nuclear test veterans. Sefton's group will be making submissions.

VOYAGE INTO TROUBLE

Sailors exposed to fallout from Britain's nuclear tests in the South Pacific may have been soaked by radioactive rain.

Crew from two New Zealand frigates were on duty during nine nuclear tests near Christmas Island - now Kiribati - in 1957-1958. Sailors who witnessed the atmospheric tests recall that after the intense blasts they could see the bones of their fingers through closed eyes.

Professor Al Rowland says nuclear veterans told him the ships sailed through ground zero after the blasts. The sailors also removed their shirts, and being the tropics it often rained.

He thinks that if the men were poisoned by radiation it would be from ingesting the radioactive water. "That's the only explanation I can think of, through their skin and inhaling and ingesting in the food. That's what I suspect is the explanation for their high translocation frequencies today."

The high level of translocations - where fragments of chromosomes were broken off and attached to others - were found with the help of a software programme used in the study. The finding was critical because they can be the first step in the formation of cancer.