Will Japan’s nuclear disaster affect the world?

UPDATE: WEDNESDAY, 9am: In breaking news, fire has broken out AGAIN at the Fukushima Daiichi No. 4 reactor. This follows a fire that broke out in the same reactor yesterday and was later extinguished with the help of the US Defence Forces.

TUESDAY, 1.40pm: A live press conference with Japanese Prime Minister and the Chief Cabinet Secretary has just taken place. Here are the updates. There is a fire burning at Reactor Number 4. The reactor did not have fuel rods in it but it did have spent fuel, which continues to emit heat and still needs to be cooled. Radiation levels from Reactor Number 3 are now at 400 milisieverts, which are at levels capable of causing instant ill health to humans. Humans become infertile at 100 milisieverts. Cooling operations continue at Reactors 1, 2 and 3.

TUESDAY, 11am: There are new reports of yet another explosion at Reactor Number 2 of the Fukushima Nuclear plant. Authorities are warning media and others not to physically approach the reactor for any reason although add ‘no significant jump in radiation has been registered’. The new blast may have damaged the suppression pool which is an important part of the containment chamber in a Boiling Water Reactor, to keep the fuel rods cooled. This news comes after it was revealed last night that the fuel rods were briefly, fully exposed.

MONDAY: There has been another hydrogen explosion at the Fukushima Plant in reactor number 3. TV news shows footage of smoke rising from the complex. Details are still coming to hand.

The crisis in Japan was today described by the Japanese Prime Minister as “the greatest hardship since World War 2” which indicates how serious the earthquake/tsunami/nuclear disaster is.

After what is being described as a mega-quake struck the region on Friday. Japan’s agencies upgraded the severity of the quake to magnitude 9.0 while the US still shows it as an 8.9. In any case, the earthquake and following tsunami resulted in utter devastation of the nation’s north-east.

More than 1000 people have been killed and 10,000 people in a north-east city unaccounted for. The city was washed away by the tsunami which struck just minutes after the earth shook. Authorities are warning of another massive aftershock in the days to come. More than 300,000 are living in emergency shelters and the operation to evacuate 215,000 from the areas surrounding the Fukushima nuclear power plant continues.

This morning, news came out that excessive radiation levels were recorded at the Onagawa Nuclear Complex in the Miyagi prefecture, the hardest hit of Japan’s regions. A state of emergency was called at the plant before levels returned to normal hours later.

That brings to three the number of nuclear plants with stability issues in Japan. But how close are they to actual ‘meltdown’ and is the situation as bad as it sounds? MM’s news editor Rick Morton top-lines it for us:

How does nuclear power work?

Einstein’s brilliant theory said it best. Energy is the product of the mass of something multiplied by the speed of light squared. In other words, the tiniest atom has an enormous, immense amount of energy. This is just to show that mass has energy, although nuclear reactions exploit a different kind of energy ‘binding energy’ in fission reactions. The reaction process results in tremendous amounts of heat being released which heats water, turns it into steam and converts it into electricity. This is the basics of a nuclear reaction. Of course, this creates a fair amount of radioactive waste which is usually diverted, captured as best of possible and stored in whatever country is poor enough to need the payment for doing so. In a nut shell.

So what is a meltdown? Is Japan experiencing a meltdown?

A meltdown is what happens when the fuel rods in a nuclear reactor melt, releasing energy and radiation outside of the nuclear reactor. What is happening in Japan at Fukushima might best be described as a partial meltdown as the fuel rods are melting themselves but not the protective dome in which they reside.

So what’s happening in Japan with the nuclear power plants?

Nuclear reactors in Japan have, as an absolute requirement, highly advanced cooling systems to prevent meltdowns. They also have emergency systems should the primary cooling mechanism fail. During the earthquake, both these systems were knocked out at Fukushima plants 1 and 2. This is the crux of the problem. Getting cooling water, or coolant, to the cooling systems and supply pumps at these plants where all basic services have been knocked out is not only extremely difficult, it is critical.

But let’s make it clear that almost all of the hazardous materials at the plants will be contained in the protective core at the nuclear power plants. The containment dome in the plants will be many times more radioactive than usual but not generally outside the plants themselves. There has already been, and may need to be in the future, more pressure release which will push-out some low-level radiation into the atmosphere. Japanese authorities claim that this is not enough to cause negative health effects.

At Fukushima, for example, authorities poured saltwater and boron into the reactor core to cool it, which may make the reactor unusable in the future.

But haven’t some people already tested for elevated levels of radiation?

Evacuees from a 12-20km evacuation radius are being screened and tested for excessive radiation levels. The Japanese Nuclear and Industry Safety Agency has stated that about 160 residents have been quarantined due to possible elevated radiation levels.

“Officials say at least three people have tested positive for radiation exposure and were being evacuated by helicopter from a hospital about two miles from the reactor. As of late Sunday evening, 12 had shown symptoms of radiation poisoning, according to the agency.

Inside the Nihonmatsu center, health officials in hazmat suits were testing residents, while Japanese Self-Defense Force troops set up a series of tents outside the building to cleanse those who had been exposed to radiation.

Troops were seen taking two people from a cleansing tent to an awaiting ambulance about 8:30 p.m.”

Wait, isn’t this another Chernobyl in the making?

No. The International Atomic Energy Association rates nuclear incidents on a scale of 1 to 7. Chernobyl, where a meltdown

occurred in reactor number 4 of the Ukraine nuclear plant, was rated the highest at number 7. It was only discovered after a huge radiation cloud was spotted drifting east over Europe. 32 people died in the aftermath and dramatically elevated rates of birth defects, deformities and cancers were registered in the region for decades to come. The IAEA rated the incident at

Fukushima as a 4, which is still below the 5 of the world’s other great nuclear incident at Three Mile Island in 1979. Yes, some radiation has been released. Yes, there is an emergency at the reactors as they race to be stabilised. But at this moment, right now, no event equalling Chernobyl has occurred. In any case, Chernobyl was an older Russian design where the Fukushima is a light water reactor of a different design.

Is Australia under threat?

No. The radiation levels are elevated slightly and only in the general vicinity of the nuclear plants in Japan.

So, should we be worried?

Only to the extent that you know people who live close to the nuclear plants. Radiation poisoning of those who have been exposed to elevated levels of radiation is a concern, obviously, but there is no worldwide threat. This is not a Chernobyl, there is no radiation cloud drifting away from Japan. Radiation levels, where they are elevated, are generally not so high as to cause cancers or adverse health effects and are localised near the plants themselves. Those who live close to the plants and who have not been evacuated have been told to cover their mouths, close doors and windows and not drink the water.

While this isn’t catastrophic this is still incredibly serious.

What are the effects of radiation?

Radiation poisoning, depending on the dosage, can result in vomiting, nausea, hair loss, birth deformities over generations, cancers and death. It is a form of tissue and organ destruction usually associated with one, single over-exposure dose. There is radiation all around you in different forms. In the microwave, on planes. Problems arise due to that one, large dose. Generally.

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