Strontium 90 - the fallout
By Peter Ewen
The nuclear industry is only some 75 years old and many scientific assumptions have been proven wrong. The American nuclear test at Bikini Atoll in March 1954 is a case in point. Its yield was over two and a half times greater than what scientists predicted. The safety issue of what to do with the growing problem of the nuclear waste is another, and the old sea dumping of waste, potentially, may come back to haunt future generations. Looking back at old news and documents of the era, such practices and acceptances of the time. may, or may not, have been a contributor to some statistics West Coasters did not want. The science community may come up with some conclusive answers to either discount, or confirm, in perhaps 100 years, what some suspect.
A Maralinga test, 800km north-west of Adelaide, Australia, carried out by the UK between 1956-63.
Why does the West Coast feature at the top of some of the nation's cancer rates -- is it because of our 'post-code' health service with the difficulties in seeing health professionals? Could practices and events of the past be a factor?
The screening last year of Chernobyl on Prime, was a chilling, captivating series.
The potential risk Europe -- and the world -- faced was truly frightening, and while most of us knew a bit about it at the time the real consequences were expanded on in greater detail during the television series. It was an eye-opener.
Russia seemed so far away that few of us were really concerned about the nuclear business and how it all worked. In the main, it was an unfamiliar subject to most.
One of the most alarming aspects of what led to the Chernobyl disaster was the ignorance and cavalier attitude of the operators of the plant, irrespective of a major design fault with the RBMK 1000 reactor.
The former Soviet Union was everything Big Brother and officials were fearful of the system -- the KGB in particular.
Safety often became secondary as a result and in a place like Chernobyl, that led to catastrophe.
Were New Zealanders and more importantly West Coasters, ever exposed to a wider nuclear risk given the Cold War era?
Circumstantial evidence suggests we could/might have been, but natural radiation does occur from rock, the Sun and particles entering the atmosphere from out of space.
Health-wise the West Coast is up there having some of the highest rates of some forms of cancer in the country, and this has to be due to something.
In saying that, the high rates could be due to lifestyle with our remoteness, leading to individuals putting off having regular check-ups.
The lack of specialists locally and having to travel huge distances to see one, could also be a factor in the region's statistics.
By the time an issue is seen to, it may be too late if it has continually been put off, so this could be a factor.
Leukaemia rates in children on the Coast are said to be high, but other regions too have similar stats.
A dangerous element Strontium 90 is a product of fission, a man-made process -- it never occurs naturally.
It is formed in nuclear reactors or during the explosion of nuclear weapons, and also from nuclear accidents.
It has a half-life of 28.8 years and generates beta particles as it decays. It takes 289 years to completely disintegrate down to a level where it is not a concern.
Radioactive Strontium is recognised as a bone seeker - it mimics calcium and if a bone is deficient in calcium, it will take up Strontium 90 in its place.
Post-war Strontium 90 was distributed through the stratosphere care of atmospheric tests. It was curiously referred to as the sunshine unit at one stage.
Attaching itself to bone and plants, this is where humans can be exposed to radioactivity through eating food grown in contaminated soil, or through drinking the likes of milk, and water.
For a number of years during the 1950s and 1960s the National Radiation Laboratory carried out what were called seasonal sampling of milk at eight stations/locations throughout the country to see what the levels of Strontium 90 were.
This product of the nuclear age keeps accumulating in the soil over time, if it continues to be part of the environment. That is why it is a health risk to humans.
During the 1960s the New Zealand average for all stations over a number of sampling periods was determined at around 6.8 Strontium 90 units.
As with most things concerned with radiation and nuclear issues in general, there is a degree of bias with the narrative. Experts differed greatly on the detail, the level of risk and what was considered a 'safe exposure'.
Whatever a unit is, some experts consider just one is dangerous, as with any radioactivity, potentially it only takes one unit to alter one cell for adverse health outcomes.
For example -- depending on who pays the salary, scientists and experts to this day have different positions on the effects of considerable contamination (plutonium) and continuing pipeline waste discharges into the Irish Sea from the nuclear facility of Sellafield, Cumbria. It was previously known as Windscale.
Tens of thousands of drums containing nuclear waste were dumped in the Atlantic, the shallow water of the Irish Sea and the English Channel, from sites like Sellafield.
Amounting to 100,000 tonnes, with 80% of that from the UK, this is a food-chain time-bomb running down as these drums are rusting away in the depths. Few today believe the spin at the time that all the drums, only contained low grade nuclear waste.
Accordingly, gauging what was once considered safe as an exposure dose to present days standards, may be considerably different.
However, in New Zealand, locational differences in Strontium 90 units levels between west and east coasts, was documented. The mountains were the reason.
The figures recorded were said by officials to be 'within the permissible levels for exposure', measured against recommendations made by the British Medical Research Council.
With the then knowledge of the risk, this was no doubt reassuring for the population, but much that was previously viewed as safe in the past for numerous things, has been found to have not been accurate.
For example -- during the time milk was tested for Strontium 90, in the Greymouth Star (March 22, 1966) an article stated: 'A spray -- 245T -- being used by the Railways Department here for spraying weeds and blackberries, is not regarded as being poisonous a department official said today. The spray is being used mainly for controlling weeds between railway tracks, but the official said that the individual gangs sometimes sprayed blackberries and other growth alongside railway lines as well. While it could be harmful if drunk from a bottle, he did not think that people who ate blackberries which had been sprayed, would be affected.'
A jaw-dropping claim now, given what we know now -- 245T is extremely dangerous.
So too is asbestos, paraquat, DDT and agent orange -- to name but a few.
Back to Strontium 90.
Strontium 90 is much less volatile that Caesium-137, but some science papers on it ominously state that it "is probably the most dangerous component of radioactive fallout from a nuclear weapon."
In high doses in children it can impair bone growth.
When Strontium 90 is ingested, about 70-80% gets excreted, but the rest is deposited in bone and bone marrow with about 1% remaining in blood and soft tissues. This continues over the length of the exposure.
Over time and with its half-life of nearly 29 years, this could be a deadly issue for an ignorant population.
During the 1950s and most of the 1960s, those old enough to remember had their daily half-pint (284ml) bottle of milk at primary school. This government scheme ran from 1937 until 1967.
Kiwi schoolchildren have a break to have their government provided milk - 1960s.
There were also no supermarkets back then so many Coasters by necessity, tendered great vegetable gardens. And other than main towns, most households relied on tank water from rainfall.
Such supplies couldn't be tested, however, the free milk in schools throughout the country could be and it was.
Many of us 50 to 60 years ago, were children who looked forward -- some reluctantly -- to downing the school milk. That item was the food-chain sample product to get a steer on what the environmental situation was at the time.
With all the tests that were carried out, unfortunately, the West Coast in the Strontium 90 stakes, always topped the poll with the highest levels.
Our location in the Roaring Forties and our high rainfall due to the Southern Alps, had a lot to do with it.
Christchurch, in the lee of the alps, had a figure usually between 2 to 3 units, the lowest in the country.
Greymouth however, following the results of one round of sampling, the report stated (verbatim) -- 'With 17.4 units of Strontium 90, Greymouth easily had the highest rate in the Dominion, while Taranaki came second with 13.8 units, Northland had 12.7 units."
Given cancer rates on the Coast, perhaps it is a physics thesis in waiting for some budding scientist to dig a bit deeper into the issue. There were levels exceeding 17.4.
High cancer rates through all age groups through the years, may be more than just coincidence for Coasters.
For one thing, it is not down to eating vast quantities of whitebait or drinking Monteith's.
Children are more susceptible than adults to the harmful effects of radioactive Strontium.