Discover N U C L E A R - B A S E D S C I E N C E B E N E F I T I N G A L L A U S T R A L I A N S
CONTENTS 3
6
a national research organisation ANSTO works across health, environmental science and materials research to find solutions to some of the biggest science questions.
4
research reactor
Neutrons are a reactor’s lifeblood. Follow their journey from the nucleus of a uranium atom, to producing nuclear medicine and facilitating cutting-edge scientific research.
6
14
research in focus From medical applications to environmental science, ANSTO research is making its mark worldwide.
12
a bright future
The Australian Synchrotron can reveal the inner structure of everything from cancer cells to proteins. Particle accelerators use different techniques to examine small samples.
14
going critical
4
In its almost 50-year lifetime, the main job of Australia’s first nuclear research reactor was generating millions of doses of radiopharmaceuticals used in nuclear medicine.
16
global exports ANSTO’s nuclear medicine program meets the needs of Australians and many more people around the globe, with these numbers set to rise.
12
Publisher Karen Taylor Editor Heather Catchpole Art director Lucy Glover Designer Alison Eaton Production Editor Heather Curry Sub-editors Keira Daley, Rivqa Rafael PO Box 38, Strawberry Hills NSW, 2012, Australia Email info@refractionmedia.com.au Copyright 2014 Refraction Media Pty Ltd. All rights reserved. No part of this publication may be reproduced in any manner or form without the express written permission of the Publisher. The views expressed herein are not necessarily those of the editors or publishers. This app was published on 17 November 2014.
DISCOVER THE iPAD EDITION This extended and immersive app combines stunning panoramic imagery, slideshows, animation, maps, graphics and video to showcase ANSTO’s achievements and innovation in an awe-inspiring interactive format. Free to download from the App Store.
2
This app was originally developed and published by Cosmos Media Pty Ltd in 2012. Thank you to the ANSTO scientists and research partners who assisted with this publication. www.ansto.gov.au
INTRODUCTION
ANSTO
a national research organisation ANSTO works across health, environmental science and materials research to find solutions to some of the biggest science questions.
E We are proudly one of Australia’s largest public research organisations.
VERYTHING, FROM OUR bodies to the air we breathe, to the floor and walls of our homes, is made up of atoms. It’s not surprising then, that the science that probes the atomic world, nuclear science, is called on by researchers in almost every other scientific field to provide the tools and techniques to support a wide range of studies. Nuclear science and technology enables researchers to go beyond the bounds of the smallest substances on the planet to see inside matter and learn how things work from the inside out. Nuclear science and technology is helping to find answers to some of the big science questions – improving health outcomes, increasing our understanding of the environment, and identifying new opportunities for Australian industry.
The Australian Nuclear Science and Technology Organisation (ANSTO) is home to Australia’s nuclear science and technical expertise. Like the CSIRO, ANSTO is an organisation funded by the Federal Government. While many Australians may not be familiar with the name ANSTO, we are proudly one of Australia’s largest public research organisations and a widely recognised international player in high-end nuclear science and technology. We operate much of our country’s landmark science facilities including one of the world’s most modern nuclear research reactors, OPAL, a comprehensive suite of neutron beam instruments, the Australian Synchrotron, the National Imaging Facility Research Cyclotron and the Centre for Accelerator Science. These facilities are used by our own scientists and visiting scientists from other local and international research organisations and universities. Importantly, ANSTO is helping to improve our health with one in two Australians benefiting from the nuclear medicines produced using the OPAL research reactor when being treated for serious illnesses such as heart disease and cancer.
3
SNAPSHOT
research reactor Words Gemma Black Illustrations Jamie Tufrey
ANSTO
If a reactor’s core is its heart, then neutrons are its lifeblood. Follow their journey from the nucleus of a uranium atom, to producing nuclear medicine and facilitating cutting-edge scientific research.
Platypus
beamlines Leading from the reactor core are four beamlines that guide neutrons to the scientific instruments in the adjacent hall, up to 40 metres away.
ANSTO
Beamline
neutrons in research Platypus is a neutron reflectometer, one of several neutron-scattering instruments at ANSTO, and is used for
4
studying the molecular structure of soft matter such as proteins in membranes. Neutrons have wavelengths comparable to the inter-atomic spacing within matter. So they can reveal the position and motions of atoms in exquisite detail. They can penetrate materials more easily than electrons and X-rays, and are particularly useful in determining the presence of hydrogen, for example to locate water
in microscopic cracks in aircraft components. Inside Platypus, neutrons are precisely directed at a sample – thin-film magnetics for computing, or proteins on a cell’s surface, for example. Samples are placed on an almost perfectly flat surface. Scientists then measure the intensity and the angles at which the neutrons scatter after hitting the sample to gather information about its molecular structure.
Translated into data, neutron scattering is a powerful tool for science.
nuclear fission
ANSTO
Neutrons striking the core of a uranium-235 (U-235) atom split the atom’s nucleus, releasing two or three neutrons – a process called fission. Some neutrons are guided down beamlines for research; others are reflected back to the core to maintain fission – a far from simple process. As the reaction continues, the number of U-235 atoms drops, and eventually new fuel rods are required. Destabilised by an incoming neutron, a uranium atom breaks into smaller atoms, releasing neutrons and energy.
irradiation facilities Inside the reflector vessel, irradiation ‘targets’ such as silicon ingots are placed alongside the reactor core, where they pick up stray neutrons. Silicon develops an atomic impurity inside the reactor; this alters its conductive properties for use in electronics. Other irradiation targets include uranium-target plates that undergo fission and produce a useful radioisotope called molybdenum-99, crucial for nuclear medicine.
Beamline
the reactor core OPAL’s reactor core comprises a 2.6 x 1.2 metre2 reflector vessel made of tough, corrosion-resistant zirconium in a 13 metre-deep pool. Protected in a high-security building with an aircraft-proof cage, the core has been compared in size to a bar fridge. Perhaps a more captivating analogy, however, would be 200,000 incandescent light bulbs: that’s roughly the equivalent heat energy – cooled by a constant flow of water – produced by the 16 fuel assemblies that comprise the reactor core, each made up of 21 uranium plates. The fuel assemblies are surrounded by a reflector vessel filled with ‘heavy’ water (deuterium oxide or 2H2O), which ‘reflects’ the neutrons back to the uranium fuel source. Spent fuel from the reactor is sent to the U.S., where it is stored or reprocessed, and may eventually be reused.
>>
5
RESEARCH IN FOCUS
NUCLEAR MEDICINE
W
HEN JOHN Kearley, a 48-year-old Sydney-based doctor, suffered a heart attack in mid-2012, his physician Louise Emmett wanted to check how this episode might affect Kearley’s future health. As part of a routine ‘stress test’ to survey the damage caused by the heart attack, Emmett, deputy director of diagnostic imaging at St Vincent’s Hospital, Sydney, arranged for Kearley to be injected with technetium-99m. This radioisotope is used in more than 80 per cent of the world’s 45 million nuclear medicine procedures every year. The technetium-99m was combined with a tracer molecule called MIBI (methoxyisobutylisonitrile), which identifies healthy heart muscle cells, revealing where damage to Kearley’s heart tissue had occurred. Gamma rays emitted as the technetium-99m decayed in Kearley’s bloodstream enabled Emmett to image Kearley’s heart at rest. Kearley then took a different medication to artificially dilate his arteries, before jumping on a treadmill to get his heart pumping for another, comparative scan. While CT (computed tomography) scans can identify heart disease and artery blockages, “it doesn’t always mean it’s significant,” Emmett says. The technetium-99m stress test helps
doctors determine if the blockage is of concern – “whether it’s going to put the patient at an increased risk of another heart attack,” she adds. After experiencing further chest pains, Kearley returned to St Vincent’s for another scan in early 2013. “I kept getting weird and unexplained pain in my chest. It’s really scary,” he says. “The nuclear medicine scan had tried to work out if there was lack of blood flow to parts of my heart muscle when I exercised – and there wasn’t. This information has removed a lot of my worries and helped me stay positive after a heart attack.”
250 hospitals and medical practices around Australia. “It’s a fantastic imaging agent,” Emmett says. ANSTO IS building an export-scale nuclear medicine facility at its Lucas Heights campus, in response to a looming global shortage of molybdenum-99, the isotope used to produce technetium-99m (see ‘Reactorto-patient delivery’). Such shortages have occurred before, and could happen again when older, existing reactors – particularly the National Research Universal Reactor in Ontario, Canada, and the High Flux Reactor in the Netherlands – are shut down in the coming years. Worldwide, reactors responsible for 70 per cent of the world’s molybdenum-99 are due to be shut down in the next few years. Australia aims to step up as a key global supplier, building a new nuclear medicine production plant in Sydney and a co-located waste facility using a technology called Synroc (synthetic rock), which reduces waste volumes from nuclear medicine byproducts by 99 per cent compared with methods such as cementation in cement-clay mixtures. “Every so often, it gets to a crisis point when there’s a global shutdown and people have to wait for their therapy and their diagnosis,” says Emmett. “In terms of treating our patients who are sick and really need treatment and diagnosis – it’s extremely important.” In addition to technetium-99m, ANSTO produces a range of other nuclear medicines, including
Nuclear medicines play a key role in cancer therapy.
6
Radioisotopes – varieties of radioactive elements – are used widely in nuclear medicine, primarily in diagnosing heart disease and cancer (the extent of melanomas, for example), two of the leading causes of death in Australia, but also for imaging the lungs, bones, brain or kidneys. Nuclear medicines play a key role in cancer therapy, targeting thyroid cancers and cancers of the bloodstream, among others. Every year, ANSTO’s OPAL research reactor provides about 500,000 technetium-99m nuclear medicine doses to more than
ANSTO
Many Australians will require some sort of nuclear medicine procedure in their lifetime. With global supplies under threat, ANSTO is stepping up to deliver radiopharmaceuticals not just locally, but also worldwide.
ANSTO
scanning for diseases
H E A LT H R E S E A R C H
I ithin the strips 1of aWreactor, uranium–
ANSTO-developed Gentech generators, and decays into technetium-99m (Tc-99m).
ANSTO
Mo-99 is ‘stuck’ to 2 aluminium oxide in
Combined with a tracer agent, 3 Tc-99m is injected into a
patient. The radioisotope rapidly decays and does not harm the body.
Gamma cameras detect the radiation emitted from 4 the Tc-99m, enabling doctors to image the body in detail.
iodine-131, used to fight thyroid cancer, and samarium-153, used for pain relief in patients with tumours that have spread to the bone. Emmett says the use of radiopharmaceuticals is growing, with exciting implications. “We’re now able to do lots of experiments with different tracer agents,” she says. “I think in 10 years, we’re going to see hundreds of new tracer agents. There’ll be a specific breast cancer agent, a prostate cancer agent, a melanoma agent, and they’ll all be labelled to these radioactive particles.” – Gemma Black
ANSTO
SPL
aluminium alloy are bombarded with neutrons. Six per cent of the resulting product is an element called molybdenum-99 (Mo-99).
N THE 1990s, studies revealed that the breakdown of starch in the large intestine can prevent bowel cancer. The obvious next step was to try to maximise this, so-called, resistant starch in foods, particularly processed foods in which the healthy starch is often lost. To do this, ANSTO scientists are using a technique called small-angle neutron scattering (SANS) to study how starch changes when it’s processed. This could lead to new ways of processing the Neutron common carbohydrate, found in bread, research can reveal biscuits and cereals. starch’s “We want to maximise the amount molecular of starch that’s left over,” explains Elliot structure. Gilbert, who leads food science research projects at ANSTO. Gilbert’s team uses ANSTO’s SANS instrument, called Quokka, to follow how enzymes break down the starch to see how readily it’s digested. With a Rapid Visco Analyser, a modified commercial instrument, his team has also been able to follow how the starch structure changes during processing along with its viscosity, like a “mini pilot-plant”, Gilbert explains. Using Quokka, scientists study the structure and behaviour of the starch on the molecular scale before, during and after processing, as well as during digestion, by firing neutrons at the starch and then measuring the resulting angles of scattering. “You can then start modifying the processing conditions to prevent the starch from being digested,” Gilbert explains. “If you can delay the digestion until it reaches the large intestine, then you maintain the cancer-preventative characteristics.” – Gemma Black
reactor-to-patient delivery THE HALF-LIFE OF technetium-99m – the time it takes for half the substance to decay – is just six hours. While key for patient safety, it’s impractical for transport. Instead, its ‘parent’ isotope, called molybdenum-99, with a half-life of 66 hours, is produced in the OPAL reactor and transported to hospitals in custom-built generators. OPAL produces all of Australia’s supplies of molybdenum-99. Inside the reactor, uranium– aluminium alloy strips are bombarded with neutrons, kickstarting the process of nuclear fission. Molybdenum-99 comprises 6 per cent of the resulting fragments on the alloy strips.
These fragments are separated and purified. ANSTO-developed generators, branded Gentech, contain the molybdenum-99 inside a lead pot, ‘stuck’ to a column of aluminium-oxide powder. From here, the radioisotopes are transported to nuclear medicine centres around Australia. At the hospital, molybdenum-99 is already decaying into technetium-99m. Vials of saline are passed through the generator, which extracts technetium-99m from the column of aluminium-oxide powder, leaving behind the insoluble molybdenum-99. The technetium99m is combined with a tracer agent for use.
7
SPL
fighting cancer with starch
RESEARCH IN FOCUS
U N D E R S TA N D I N G O U R E N V I R O N M E N T
an element of time
W
E LIVE IN a radioactive world. From bananas and brazil nuts, to the nuclear fusion reactor that is the Sun, the radiation of energetic particles – often at minute and therefore harmless levels – occurs all around us, all the time. That’s why the Gamma Spectrometry Control Room, where ANSTO scientists use gamma spectrometry to unveil the history of environmental changes, is built tough. The least radioactive space in Australia, it is made from special low-radiation concrete to prevent interference from naturally occurring background radiation. The resulting research provides key insights into climate change – past and future. Henk Heijnis, a senior scientist at ANSTO’s Institute for Environmental Research, leads the Isotopes in Climate Change and Atmospheric Systems project. His team looks for certain radioisotopes – radioactive elements with a specific number of neutrons – that, thanks to their known rates of decay, can reveal the age of sediment cores. Then, working with universities studying other properties of the sediments, they can begin to paint a picture of a changing landscape over time. “The sediment core is like a history book of past environments,” Heijnis explains. Researchers place 2.5 mm slices of the core – the book’s ‘pages’ – inside a petri dish, then into a gamma
8
spectrometer. The gamma radiation emitted by the sample pinpoints radioactive isotopes and uncovers the story of what has happened in the environment over time. Elements such as lead-210, with a half-life of 22 years, are useful to study processes “in the past 120 years or so,” says Heijnis. “It can tell us a great deal about what happened in a region in the late 19th century and the whole of the 20th century.” Hydro-geochemist Karina Meredith, from ANSTO’s Isotopes for Water project, uses similar methods to analyse Australia’s water supplies and groundwater systems, such as the Gnangara groundwater system, which supplies up to 70 per cent of Perth’s tap water. “Knowing the age of the water is essential for understanding how frequently water is being replenished into the underground rocks or aquifer system,” she explains. The researchers focussed on a short-lived radioisotope called tritium – with a 12-year half-life – to determine the age of ‘younger’ waters. Radiocarbon dating is used to determine the age of older waters. “We discovered an area of younger waters, indicating groundwater replenishment is occurring at a faster rate than anticipated,” says Meredith. Such studies have significant implications in understanding the complexity of Australia’s rivers and groundwater systems. – Gemma Black
ANSTO scientists use radioactive isotopes to determine how fast groundwater is replenished.
ANSTO
Earth scientists are using geology’s natural radioactive ‘clocks’ to better understand climate change and manage our environment.
I N N OVAT I O N A N D I N D U S T RY
using your smarts As with any big science research organisation, core research can drive spin-off commercial success stories.
J
West secured a licence agreement for the technology and founded the company, BioGill Environmental Pty Ltd, which, in 2012, purchased all the intellectual property from ANSTO, with a view to export products globally and diverge into new market applications. BioGills are now successfully treating grey water, sewage and many different industrial wastewater streams such as effluents from breweries, wineries, food manufacturing and detergent plants. Collaborating with industry and commercialising technology is part of ANSTO’s mandate to “add value to the Australian economy and enable job creation,” says Rosanne Robinson, who manages business development at ANSTO. ANSTO’s research into sol-gel chemistry also initiated a spin-off subsidiary in 2007 called Ceramisphere and the company was privatised in 2010. Ceramisphere uses nano-sized ceramic (or silica) spheres to provide encapsulation and controlled release of active molecules for a range of applications including pharmaceuticals and anti-corrosion coatings. – Gemma Black
iSTOCK
OHN WEST WAS at an event at ANSTO when a new technique to treat water using nanoscale membrane technology caught his interest. An entrepreneur with his own business, he was immediately intrigued, and started a discussion on the research with ANSTO scientists. The nanoparticulate membrane bioreactor (NMB) treats wastewater using bacteria and fungi on a special porous membrane – a key to the design’s efficiency. “Most bioreactors have bacteria submerged in water, so the issue is a lack of oxygen, which makes them very slow to operate,” West explains. To counter this, membranes in the NMB design are ‘seeded’ with bacteria and fungi, and installed above ground, promoting micro-organism growth as they feed on the nutrients and toxins in the water. The invention stemmed from broader ANSTO research into applications for ‘sol-gel’, a matrix of solid nanoparticles dispersed in a liquid. Small-angle neutron scattering techniques revealed how the matrix of nanoparticles can be precisely modified to meet specific needs.
9
RESEARCH IN FOCUS U N D E R STA N D I N G AG E I N G
protein structure and alzheimer’s
T
10
ANSTO
HOUSANDS OF Australians live with Alzheimer’s disease or dementia, with the number expected to skyrocket as the population ages, with 2 billion people expected to be aged over 60 by 2050. An effective treatment, let alone a cure, remains elusive, but a key step forward could lie in an improved understanding of a single protein. Called the translocator protein, it is found in cells throughout mammal tissue where it plays several important roles, including in stress regulation. Its presence in the brain, however, is a sign of inflammation, which can be caused by injury, or neurodegenerative diseases including Alzheimer’s and multiple sclerosis. Biophysicist Claire Hatty recently completed her PhD with ANSTO and the University of Sydney, studying the translocator protein. “We want to understand this protein at the molecular level, so that we can better understand its role in neuro-inflammation,” she explains. “If we can better understand what it is doing and how it’s contributing to that process, we might eventually be able to create drugs that can modulate and even reduce the inflammation,” she adds. “It’s far-reaching, but it’s what we’re hoping for.” While the research is still in its early stages, Hatty, with instrument scientist Anton Le Brun from ANSTO, is using the Platypus neutron reflectometer to study the structure of the protein to figure out why it “suddenly appears when there’s neuro-inflammation”. By firing neutrons at a synthetic cell membrane embedded with the protein,
Biophysicist Claire Hatty studied a brain protein that could provide new insights for diagnosis and better treatment of diseases, such as multiple sclerosis and Alzheimer’s disease.
An MRI scan (left) shows the structure of the brain, while a PET scan (right) reveals areas of inflammation.
the researchers are hoping to reveal how it interacts with various binding molecules, including specific drug molecules and tracing agents. The protein could also be useful as an imaging agent, with other researchers at ANSTO studying, in parallel, its potential use in brain scans – offering the possibility of earlier diagnosis for people with Alzheimer’s disease. At present, Alzheimer’s can only be diagnosed when symptoms, such as memory loss, are serious – which may be too late for any effective treatment. “We’re using techniques that have traditionally been used in physics,” Hatty says. “I find it interesting how we can apply them to biology.” – Gemma Black
iSTOCK
The tools traditionally used by physicists can help biologists to decipher the processes of ageing and disease.
greener electronics GLOBALLY, ANSTO IS the leading provider of silicon irradiation services for the power electronics industry. Irradiating silicon, a process called neutron transmutation doping (NTD), changes electronic properties of silicon, making it more conductive of electricity. Silicon ingots ‘doped’ at ANSTO are used to manufacture a variety of devices in which quality is critical such as those used in industries including the automotive industry for hybrid cars; transportation for high-speed trains and; energy and renewable ‘green’ energy such as wind power. To achieve higher power densities, size reduction, and allow the device to operate at higher temperatures, both the device and the silicon wafer used in its manufacture should be of the highest quality. Some of the highest quality silicon wafers around the world are produced from NTD silicon ‘doped’ at ANSTO. “By 2050, it is predicted 40 per cent of the world’s energy demand could be provided through energy savings and much of these savings will be from devices made out of NTD silicon,” says Tatiana Karma, who manages ANSTO’s silicon irradiation business. “It gives us a chance to contribute to making our planet greener.”
U N D E R STA N D I N G T H E E N V I RO N M E NT
I
N 2002, Henk Heijnis, a senior scientist at ANSTO’s Institute for Environmental Research, went on a field trip with colleagues to a remote southwest corner of Tasmania. They went up the Gordon River to a landing site where initial works had been undertaken for a dam – before protests famously saw the project abandoned. Aside from the odd bushwalker, those 1980s works and protests were the only modern human interference the region had ever seen. “We were thinking, we won’t pick up any human signals,” Heijnis says of the sediment core research they were to undertake, believing that the signals they would find would be naturally driven – produced by climate and rainfall.
Tasmania’s wilderness areas seem unspoiled, but earlier human activity has made these regions less pristine than previously thought.
They studied a 7.5 cm sediment core from a subalpine lake. The sample showed contamination with heavy metals, including zinc, lead and copper, in excess of Australian and New Zealand safety guidelines, and evidence of the surrounding area’s mineral prospecting and associated history of logging. Using gamma spectrometry for lead-210 analysis, the researchers dated the sample to about 1811. They linked the sediment layers to specific periods in Tasmania’s history, such as a reduction in vegetation around the 1860s, associated with elevations in charcoal and trace metals due to tree clearing by burning. The period from the 1950s to the 1970s – when open-cut mining
I N D U ST RY & I N N OVAT I O N
smart rock technology
A
USTRALIA GENERATES very little nuclear waste compared to countries with larger nuclear programs. So when Australian geophysicist Ted Ringwood came up with the most promising method yet for securing high-level nuclear waste back in 1978, while working at the Australian National University in Canberra, it was a case of a minor producer of nuclear waste punching well above its weight. Ringwood, who died in 1993, was analysing rocks from Sri Lanka and the Italian Dolomites when he noticed they contained radioactive elements such as thorium and uranium, as well as their decay products. The rocks had been exposed to the environment and immersed in groundwater for millions of years, without releasing any dangerous radioactive material, Ringwood discovered. He coined
the term Synroc, a portmanteau of synthetic rock, and took his idea to what was then the Australian Atomic Energy Commission. “Nature had shown him a way to lock up radioactive waste,” says ANSTO materials engineer Sam Moricca, who has overseen the transition of Ringwood’s idea to a viable product over the past 25 years. Synroc stores nuclear waste in a crystalline structure of minerals based on those already found to lock up radioactive elements in rocks in nature. These are compressed in stainless-steel canisters using argon gas, inside a 1200°C furnace. ANSTO’s Synroc team has adapted the latter compression method, called hot isostatic pressing, to secure nuclear waste for the Idaho National
Australian invention Synroc stores nuclear waste more safely than existing methods. ANSTO
123RF
an environmental legacy
escalated in Tasmania’s west – showed the biggest impact in reductions in vegetation, the researchers found. Heijnis says the results could have ramifications for mine site rehabilitation, suggesting the existing focus on direct run-off from polluted rivers should be supplemented with heightened consideration of aerial contamination by fine particles. “So, the study was useful on many levels and can inform our current mining practices. It’s very difficult to define a pristine area,” he says. “Ecologists and biologists keep talking about that, but I think with a little bit of geochemistry knowledge – the stuff we do – using nuclear techniques there is no way to hide. We can certainly confirm that some locations are not as pristine as they seem.” – Gemma Black
Laboratory, and to immobilise dangerous plutonium residues for the UK National Nuclear Laboratory. While the current favoured technology for storing high-level waste around the world is to dissolve it in glass, Synroc has the ability to lock up radioactive waste “thousands of times better than glass,” says Moricca, “because it locks the radioactive element into the structure, as opposed to just having it dissolved there.” In 2010, ANSTO set up a subsidiary, ANSTOsynroc, with a view to commercialising the technology. ANSTO is building the first operational plant to process nuclear waste using Synroc, as a demonstration facility for the rest of the world. “People worldwide are sold on the superior properties of Synroc to lock up radioactive waste,” says Moricca. “Once we have our plant in operation, it will open the doors to many opportunities to treat waste around the world.” – Gemma Black
11
X- R AYS A N D I O N B E A M S SYNCHROTRON
a bright future
T
HE AUSTRALIAN Synchrotron produces intense light to reveal the inner structure of everything from cancer cells to proteins and works of art, and can image materials at nanoscales. It operates on similar principles to the famous Large Hadron Collider, but with a focus on producing extremely bright X-ray beams to reveal the molecular structure of materials, rather than the fundamental forces of nature. Recent research ranges from mapping the nutrient content of rice grains, to releasing the first 3-D images of insulin in the process of binding to cells. Here’s how it works.
electron gun Generates electrons by heating a matrix of tungsten, and accelerates the electrons to an energy of 90 kiloelectron volts (90,000 electron volts, or eV). In the cathode ray tubes of old fashioned televisions, electrons are accelerated to about 20,000–30,000 eV.
linear accelerator In just 10 metres, electrons are accelerated to 99.99 per cent the speed of light and an energy of 100 megaelectron volts (100 million electron volts).
The Australian Synchrotron has capabilities far superior to those of standard laboratory instruments.
TONY GAY/DIGITAL IMAGE
12
end station Within the mostly remotely operated end stations, instruments collect data from samples illuminated by the beamlines. The intense light generated by the synchrotron can be anything from X-rays to infrared light, and can be used in research from determining the mechanics of cell death to exploring the possibility of storing hydrogen in nano-thin films of diamond.
beamlines Beamlines capture the emitted X-rays, select specific wavelengths, and focus them onto a sample for research.
storage ring Stored electrons are held in the 216 metre circumference ring continuously for days, with the electron current ‘topped up’ from the booster ring every few seconds.
J. MILLER
TONY GAY/PHOTOSHELTER
ACC E L E R ATO R S
fast particles
Particle accelerators use different techniques to determine the age and composition of tiny samples, making them key research tools across a broad range of scientific disciplines.
B
Y FIRING CHARGED particles called ions at a few per cent of the speed of light at small samples, scientists can detect a single atom among a quadrillion and reveal a sample’s elemental composition and in some cases its age as well. This is what goes on inside ANSTO’s particle accelerators, where applications range from finding the source of air pollution to uncovering evidence of covert
PAUL K ROBBINS
At the Australian Synchrotron, scientists study the structure of materials using intense light beams generated by electrons circulating in the main accelerator (storage ring).
booster ring In half a second, an electron in the booster ring completes more than one million laps of the ring’s 130 metre circumference, and is accelerated to an energy of 3 gigaelectron volts (3 billion electron volts).
ANSTO’s ANTARES accelerator creates high-energy ion beams ideal for dating small methane samples, for example.
Scientists use ANTARES for a variety of research applications, including, recently, characterising air pollution in Asia and Australia.
uranium enrichment for the International Atomic Energy Agency. Ion-beam analysis is one of two key capabilities of ANSTO’s four particle accelerators, STAR, ANTARES, VEGA and SIRIUS. When an ion hits atoms in a sample, it ‘excites’ electrons, generating X-rays with energies characteristic of the individual elements in the sample. Looking at these energies and their numbers, scientists can trace back the original components of the sample. Just two of the four accelerators that make up the Centre for Accelerator Science, STAR and ANTARES, accelerate particles at different energies (up to two and 10 million volts, respectively), allowing a broad range of different particles to be accelerated. This in turn allows for a greater variety of research applications. “We tailor the ion beam to suit the problem,” explains David Cohen, head of accelerator science at ANSTO. For example, to study the entire elemental composition of an air pollution sample, a light, energetic ion beam would be accelerated to pass right through the sample. On the other hand, a scientist could study just the first atomic layer of a sample using a heavier, slower, less energetic ion beam. – Gemma Black
13
HISTORY
going critical “
T
HIS REACTOR HAS saved a lot of lives,” says education officer Marian Jones in quiet awe as we emerge from a fortified airlock chamber into the dim interior of the HIFAR, Australia’s first nuclear reactor, now shut down. She’s referring to nuclear medicine produced here that benefited a generation of Australians in its 49 years and four days of operation. The building that houses the British-designed HIFAR, at Lucas Heights in southern Sydney, stands 21 metres tall and wide – an impressive white monolith with a domed roof. The reactor, deep in the building’s
14
core, was kickstarted on 26 January 1958 – a process called ‘going critical’. HIFAR was managed by the Australian Atomic Energy Commission (AAEC) and officially opened in 1958 by Robert Menzies, who was Prime Minister at the time. It was a momentous occasion in the history of Australian science. “We’re opening an establishment related to something so new in the world,” Menzies said at the opening, “that it’s not so many years ago that nobody, non-scientific at any rate, had thought of it.”
Australia’s first reactor, HIFAR, now shut down, is today a reminder of how far nuclear research has come since the 1950s.
As public opinion in the proceeding decades swung on the benefits and risks of nuclear energy, this little-known reactor’s job – with its modest 7 kg fuel load and 10-megawatt (MW) thermal output – was purely nuclear medicine production and research. HIFAR became a tool crucial for medical radiopharmaceuticals, and for scientific research in general. Accompanying Jones on our tour is nuclear and mechanical engineer Pertti Sirkka, who started work at HIFAR in May 1977. He points out
HIFAR became a tool crucial for medical radiopharmaceuticals, and for scientific research in general.
MAX DUPAIN/ANSTO
In its almost 50-year lifetime, the main job of Australia’s first nuclear research reactor was generating millions of doses of radiopharmaceuticals used in nuclear medicine.
123RF MAX DUPAIN/ANSTO
Robert Menzies, Australian Prime Minister at the time, officially opened HIFAR in 1958.
In the 20 years before closing in 2007, the HIFAR reactor produced most of Australia’s nuclear medicines and operated on a charter that focussed on scientific research rather than nuclear power generation.
the decades of scuff marks at the foot of the control room chair, left by hundreds of successive engineers overseeing operations in front of an array of dials and switches. In 1969, the Federal Government, headed by John Gorton, proposed construction of a 500 MW nuclear power plant in Jervis Bay, south of Sydney. Plans progressed as far as land clearing and pouring concrete at the proposed site. However, a new Prime Minister, William McMahon, was opposed to the idea and the project was abandoned by mid 1971. It was the first and last time a nuclear power plant was seriously tabled as an option in Australia. By the 1980s, with nuclear energy off the agenda, parts of the AAEC split to join with Australia’s other national science agency, the CSIRO. The remainder was renamed the Australian Nuclear Science and Technology Organisation, or ANSTO, in 1987, and
began operating under a new charter that focussed on science research. For the next 20 years, HIFAR continued to produce most of the country’s nuclear medicines and much of the world’s neutron-irradiated silicon – the heart of all computer chips, such as microprocessors – and facilitated important nuclear science and technology research. Sirkka was working as operations engineer at HIFAR when Senator Julie Bishop stood in Menzies’s place to officially close the reactor on
30 January 2007 – just shy of its 50th anniversary. “HIFAR had operated well past all expectations,” Sirkka says. HIFAR was replaced with a state-ofthe-art, Argentinian-designed 20 MW research reactor called OPAL, which went critical in August 2006 and officially opened in April 2007. “OPAL feels entirely different and modern,” says Sirkka. “But engineering challenges are generic, and hence no less challenging or interesting than on an old reactor design.” As HIFAR did, OPAL now produces vital nuclear medicines for Australia and Australasia and irradiates almost 30 per cent of the world’s silicon for high-power electronics for energy infrastructure and transport. Beaming neutrons to a hall of world-class neutron-scattering instruments, it is also the hub of nuclear science in Australia, used by scientists from research institutions here and around the world. – Gemma Black
opal is a research reactor HIFAR AND OPAL are designed to generate neutrons, and are vastly different to nuclear power reactors. Power reactors have cores with hundreds of times more uranium fuel and use the process of fission – the splitting of atomic parts – to create heat to drive energy production. Research reactors are used by scientists to learn about the molecular structure of materials using techniques such as neutron scattering. These techniques can address issues from tackling climate change to finding energy-efficient power sources for the future.
15
>>
ANSTO
HEAD IN HERE
SPECIAL REPORT
global exports
ANSTO’s OPAL reactor makes many of the world’s medical scans possible.
T
OKYO. AN ANXIOUS 42-year-old woman faces breast cancer surgery tomorrow. She has just had a tiny amount of the radioactive element technetium-99m injected into her breast ahead of a scan that will tell her surgeon which lymph nodes to biopsy – thereby increasing the effectiveness of her operation. She doesn’t know it, but her scan relied on ANSTO’s OPAL reactor in Sydney, which was designed for nuclear medicine and research. Radioactive molybdenum-99 (which decays to make technetium-99m), arrived just in time to get through customs and be rushed onto a Qantas flight to Tokyo. On landing, it was rushed to a nuclear medicine processing company, where
a half-life of just six hours, which means half of it will have decayed into something else in that time. This is why it is shipped as its precursor, molybdenum-99, which has a half-life of 2.75 days. ANSTO’s molybdenum-99 exports bring in over $10 million each year to Australia. This figure is set to triple after 2016, when its new $100 million nuclear medicine processing facility starts up, bringing with it 250 new jobs. “This will allow us to provide about 25 per cent of the global volume of molybdenum-99 and, with our joint venture South African partners NTP, supply about 50 per cent of the world market,” Jenkinson says.
ANSTO’s molybdenum-99 exports bring in more than $10 million each year to Australia. it was incorporated into a ‘generator’ – a heavily shielded device about the size of an esky – then couriered to the hospital, where the minute dose of technetium needed for her scan was drawn off. ANSTO has this process of sending time-critical nuclear medicine supplies across the globe down to a fine art, regularly shipping molybdenum-99 to Asia and the USA. “We can get product from Sydney to Boston as efficiently as it can be shipped there from Europe,” says Shaun Jenkinson, ANSTO Nuclear Business Group Executive. With radioactive elements, time is of the essence. Technetium-99m has
16
Most of the main reactors producing nuclear medicines are fuelled by highly enriched uranium (HEU) in the U-235 isotope, as well as HEU ‘target plates’ for making molybdenum-99. HEU is also a critical component for nuclear weapons. Hence, the use of HEU is discouraged in accordance with an international treaty on the non-proliferation of nuclear weapons. The OPAL reactor, however, is technologically advanced in that it uses low-enriched target plates when making molybdenum-99 and runs on low-enriched uranium fuel, which cannot be diverted to weapons. “We lead the way – being good citizens of the world by supplying
ANSTO
ANSTO’s nuclear medicine program meets the needs of Australians and many more people around the globe, with these numbers set to rise.
a product that’s proliferation-proof,” says Jenkinson. In Australia, ANSTO is the major supplier of technetium-99m in nuclear medicine. “About 600,000 Australians have nuclear medicine scans every year,” says Professor Paul Roach of the Royal North Shore Hospital in Sydney. Since only minute amounts are needed for each scan – including bone, cardiac, lung, thyroid and kidney scans – the entire Australian market uses just 60 ml of molybdenum-99 per week. But not all nations are self-sufficient in this way. “There have been real issues in the USA when people have struggled to get technetium because the old reactors have been down for repair,” says Roach. As North America’s older reactors retire from service over the next two years, ANSTO is well-placed to increase its output, and take up the challenge of providing the necessary medical exports to a growing global market. – Clare Pain
HEAD IN HERE
Nuclear science and technology benefiting all Australians Environment
ANSTO researchers use nuclear techniques to study our environment,
Health
produce nuclear medicines to aid diagnosis of diseases such as cancer,
Solutions for industry
and support Australian industries including developing clean energy devices.
www.ansto.gov.au www.facebook.com/DiscoverANSTO www.twitter.com/ANSTO
COSMOS 50
17 years of discovery
>>