The Chernobyl Conundrum Is Radiation As Bad As We Thought?
Part 2: Was the Fukushima Evacuation a Mistake?
Otherwise, the reactor catastrophe in Fukushima has had relatively mild consequences. Almost 19,000 people in the region lost their lives, but they were victims of the earthquake on March 11 and the subsequent tsunami. So far, no one seems to have died as a result of radiation from the damaged nuclear power station. Two workers came into contact with radioactive water because they were wearing low-cut shoes and were hospitalized with minor burns, but they were promptly discharged. In contrast, many people died as a consequence of the widespread evacuation. Almost 100,000 inhabitants of the area surrounding the power plant had to leave their homes: The ill were removed from intensive care units, the elderly taken out of care homes and families were split up. Some had to be resettled several times. Many of those in the makeshift shelters complained of depression. There were suicides.
The most conservative assessments assume there were at least 150 fatalities. A study conducted by the University of Stanford concluded that there were 600 victims of the evacuation, compared to the maybe 30 that would have died of radiation poisoning had they not been rescued.
The radioactivity in the region of Fukushima remained relatively low. According to the World Health Organization (WHO), no more than 50 millisieverts were to be expected in the first year, even in the worst hit localities, and up to 10 millisieverts in the other surrounding areas.
So was the complete evacuation a mistake? Should people have simply been left at home? Or perhaps only infants, who are especially vulnerable, should have been evacuated?
These questions are easy to ask in hindsight. But for one querulous group of researchers, there are no doubts. They believe that weak radiation doesn't hurt the body, but in fact helps. They say the minor radioactive bombardment can be beneficial: Cells power up their repair systems and enter a state of increased vigilance and vitality.
This theory is called hormesis (the word comes from ancient Greek and means "stimulate") by its proponents. The scientists who adhere to this approach meet at special conferences and even have their own journal. Their leading authority is the American toxicologist Edward Calabrese of the University of Massachusetts in Amherst.
The proponents of hormesis, or "hormeticians," find the prevailing risk model to be too pessimistic. There are places, they say, where the natural background radiation emanating from the planet is far higher than normal doses, including the Guarapari resort in Brazil and the radioactive thermal springs in Ramsar, Iran. Yet in these places, there are no indications of an increased risk of cancer.
Still, the skeptical majority of researchers is not convinced. They point out that cancer statistics are notoriously unreliable at low doses of radiation. Some cases in such places, they argue, might indeed be caused by radiation, but they cannot be identified due to the numerous cases resulting from other causes.
The Bavarian radioactivity researcher Rühm fears that the debate will never be settled with statistics alone. "We need additional biological experiments in order to understand what the effects are of radiation in small doses," he says.
The research project on radon therapy in Darmstadt shows how this might work. The researchers are not only examining spa guests, but have also placed mice in a specially constructed radon chamber and are monitoring the cell cultures in an artificial blood stream.
It has already become clear that, under radiation exposure, specific cells emerge that reduce the immune system's overzealousness, preventing the body from becoming its own enemy.
Is this then evidence in favor of hormesis? "This theory about positive radiation is too general for me," says project leader Fournier. "The damaging effects are still there." As such, she would not recommend radon therapy to a healthy person. "But in the case of the ill, the benefits seem to clearly outweigh the negatives."
The Benefits of Poison
The hormeticians are still in the minority. But the Nuclear Regulatory Commission (NRC) in the US is currently looking to answer the question of whether their risk model should incorporate hormetics in the future. Last year, the commission invited experts to share their views and the process is still ongoing. A subcommittee has already expressed its view, however: It believes the commission should stick to its current model for the moment. Hormesis is still too unproven, they say, even if it does appear increasingly plausible.
It is the same plausibility of an old piece of folk wisdom put forward in the 16th century by the healer Paracelsus, namely that the dose makes the poison. It is true that many things are good for the body in moderation. Salt for example, or the stimulant caffeine -- substances that are deadly in higher doses.
The Greifswald pharmacist Hugo Schulz observed in 1888 that yeast thrives after being treated with a significantly diluted disinfectant. Schulz saw his findings confirmed after tests with other poisons. Under a certain threshold, the usual effects are reversed and toxins become useful.
Schulz was a pioneer of the hormesis theory. Later on he tried to use his discoveries to explain homeopathy, as it also calls for poison to be taken, albeit in vanishingly small amounts. Today's hormeticians find the field's founding father's confusion to be embarrassing.
In Jena, the biochemist Wetzker is unfazed. He and his team of two dozen researchers are investigating how the body's cells react to stress. He is looking at heat, cold, hunger, poisons and radioactive materials. "In small doses, these are completely normal challenges for the body," says Wetzker.
The cells respond in the same way to all forms of stress. First they amp up their powerhouses, the mitochondria, and mobilize their energy reserves. Invariably this process produces oxygen radicals. "Previously these were thought of as a bad thing," Wetzker says. "Today we know better. Their attacks stimulate the cell's repair processes."
Caution Is Required
This molecular skirmish appears to invigorate the organism. Various findings point towards the conclusion that moderate stress of any kind is advantageous. Roundworms fed small amount of arsenic live longer. People who indulge in moderate levels of alcohol have reduced risks of heart attacks, diabetes and Alzheimer's according to epidemiological studies.
Yet these blessings do seem to be coupled with notable damage to genomes. But this is as true of exercise as it is for other sources of stress. "Even when you jog," says Wetzker, "the genomes in your cells come under attack." In this instance, the impact leads to muscles being strengthened.
Wetzker hypothesizes that there is a universal principle when it comes to stress response, namely that the body can acclimatize to -- or even requires -- any kind of moderate challenge. "After a few weeks in a cast, your muscles are withered." The body needs to be regularly pushed, even with radioactivity.
Wetzker, of course, admits that caution is required when it comes to nuclear radiation. It is too difficult to calculate doses and effects. Experiments on people to gain better insights are out of the question. The researcher believes, however, that there are ill people who would be willing to accept a small amount of risk.
Every year, around 56,000 people in Germany die as a result of septicemia. This usually devastating blood poisoning is most often contracted in hospitals -- already weakened patients are especially susceptible. Strangely though, death usually comes long after the pathogens have been removed from the bloodstream with antibiotics. Even without the harmful microbes, the patient gets worse and worse. Usually their illness comes to a close as multiple organs fail. As such, it has long been suspected that the immune system itself is to blame. It could be overreacting to the original infection.
A New Debate
Wetzker hopes he can use mild radiation to calm the out of control defense mechanisms. The idea first occurred to his colleague Luis Moita at the University of Lisbon. Moita had already proven in several tests on mice that he was on the right track. The majority of the animals subjected to radiation survived the septicemia.
"For us, this is a sensational discovery", said Wetzker. "Maybe we can save humans this way too." Moira had previously infected several mice with a cytotoxin, which damages the genome and simulates exposure to radiation to some extent. This method has already been approved and is used to fight blood cancer by attacking leukemia cells.
A study has already been requested. Septicemia patients who, according to medical estimates, do not have long to live are being considered as the subject group. The plan is to offer these terminally ill patients the radiation simulant. It would be their last hope.
If they survive, then researchers will be facing a new debate -- about the curing power of destroyed genomes.
- Part 1: Is Radiation As Bad As We Thought?
- Part 2: Was the Fukushima Evacuation a Mistake?