Radioactive pollution doesn’t just leak from nuclear installations in emergencies and accidents. It is emitted from them, legally, every single day. These licenced emissions and controlled releases are necessary for the proper functioning of nuclear facilities and they release into the atmosphere and the environment a range of dangerous cancer-causing radioactive particles.
Since the discovery of cancer clusters around the Sellafield nuclear reprocessing plant in 1983, several studies have revealed similar clusters around other nuclear facilities in and around the UK.
Clusters of childhood cancer, where the risks are anywhere from 8 to 15 times greater than would be expected, have, for instance, been confirmed in the vicinity of the nuclear reprocessing plants at Sellafield, Dounreay and Cap de la Hague in northern France.
In Burnham-on-Sea in Somerset, near the Hinkley Point nuclear power station, the risk of cervical and kidney cancer is around six times the national average, leukaemia rates are four times and breast cancer twice the national average.
In Maldon along the Blackwater estuary in Essex, discharges from the Bradwell nuclear power station mean that women have a 30 per cent higher risk of contracting breast cancer and twice the risk of dying from the disease compared to those not living near a nuclear facility.
Blowin’ in the wind
According to Dr Chris Busby, a Fellow of the University of Liverpool in the Faculty of Medicine, and co-founder of the environmental consultancy group Green Audit, ‘The link between Sellafield and excess childhood cancer is now indisputable,’ and the process through which people become contaminated is linked to the unique environmental conditions of the area.
Radioactive discharges into the air and the sea from the plant are contaminating the Irish Sea with radioactive uranium, plutonium, americium, caesium and Strontium and this material is then blown back to the land by sea spray.
‘Once there’, says Richard Bramhall, Secretary of the Low Level Radiation Campaign (LLRC), ‘there’s an ecological sorting mechanism. The radioactivity adheres to the finest particles of sediment and that sediment eventually settles out where tidal energy is the least. When the water comes to a standstill, the particles fall out and drop down to the bottom and the water gradually recedes.’
This process is ongoing in estuaries and mud fl ats and around the coast where the particles are either churned up into the air by the tides or become airborne on the back of dust as mudflats and estuaries dry out. As this happens, the particles can easily get into lungs or onto crops and be ingested with food. Once inside the body, they release powerful bursts of radiation directly into body tissues.
In spite of accumulating evidence that emissions from the area’s nuclear facilities – Sellafield in particular, but also Oldbury and Hinkley Point – are to blame, government bodies, like the Committee on Medical Aspects of Radiation in the Environment (COMARE), set up at the time of the very first enquiry into the Sellafield child leukaemia cluster, and the Committee Examining Radiation Risk from Internal Emitters (CERRIE) reject the claim that nuclear radiation is the cause of these cancers. Instead they argue that:
¡ö the doses of radiation received by the children are too small to cause harm;
¡ö that humans have been exposed to natural radiation for years with no discernible harmful effects;
¡ö that the excess cancer rates are probably best explained by a hypothesis known as ‘population mixing’.
Not much radiation
The fundamental differences between dissenters such as Busby and Bramhall and the pro-nuclear establishment centre largely around the science of low level exposures, as well as important differences between the harm caused by external and internal exposure to radiation.
As with any poison, the route of exposure is as crucial as the dose. And the problem, says Bramhall, is that official tables and calculations used by government committees to assess the risk of inhaling radioactive particles are based on data derived from survivors of the Hiroshima bomb, who received massive external blasts of radiation.
Bramhall describes the difference this way, ‘You can get a certain amount of warmth into your body by standing in the sunshine for half an hour. You could quite conceivably get the same amount of warmth into your body by eating a hot burning coal plucked from the fire. Obviously the results of one are beneficial and the results of another are fatal. But as far as the current radiation risk model is concerned, both are understood in the same way.’
Of the three types of radiation that can be released from a nuclear facility – alpha, beta and gamma – it is alpha-emitting particles, or ‘hot particles’, that make up the majority of emissions from power stations, reprocessing and refuelling facilities. These appear to do
the least damage externally because, while they contain a great deal of energy, they do not penetrate the skin deeply.
Once inside the body, however, they do not need to penetrate deeply to cause damage. Locked onto a single cell, they are powerful enough to cause the kind of genetic mutations that lead to cancer.
Studies show, for instance, that hot particles such as plutonium-239, widely heralded as the nuclear fuel of the future, may be 10 to 1000 times more effective in producing cancer with an internal exposure than with an external one.
The internal effect is important since every cancer starts in a single cell and the damage from chronic exposure to internal radiation, according to Chris Busby’s theory, occurs because the decay of some radioactive particles – which releases regular pulses of radiation to the surrounding body tissues – delivers a lethal one-two punch to cellular DNA.
Our cells have the amazing ability to repair mutations, and when a sub-lethal dose of radiation (or any pollutant) causes damage, it triggers an irreversible 8-hour repair sequence. During this process the cell is vulnerable and unable to affect a second repair to any additional damage it receives. In an individual who is inhaling or ingesting radioactive particles daily, the likelihood of a cell sustaining two damaging ‘hits’ of radiation within an 8 hour period is high, increasing the probability of pre-cancerous mutations that never get repaired.
In October 2004 CERRIE’s first report into the risks of exposure to radioactive pollution, acknowledged that regulators needed to be cautious in assessing the risks of different types of exposures and that there remained a number of uncertainties in our understanding of the harm caused by internal radiation exposure, particularly in children. Because of these uncertainties, it continued, the likely risks associated with long-term internal exposure to low-level radiation could be underestimated by a factor of 10. The report also recommended that policy makers and regulators consider adopting the Precautionary Principle when dealing with these uncertainties.
‘Man made’ radiation
Many of the radionuclides emitted from modern nuclear facilities are ‘manmade’ and did not exist on earth prior to 1945. Once again, not taking this into account means that current models, based on exposures to naturally-occurring radioactive particles, can be poor predictors of risk.
These man-made particles are often compounded with natural elements, such as potassium and iodine, and so have a chemical affinity that draws them like magnets to certain organs and tissues of the body. This affinity is why radioactive particles are used so widely in targeted chemotherapy. In the body these radioactive elements become interchangeable with biologically important elements and irradiate body tissues in novel ways that make them a potentially serious mutagenic hazard, the magnitude of which cannot be understood by looking at studies of external acute exposures like those received by Hiroshima victims.
The Chernobyl accident, say Richard Bramhall, is a good example of such interactions. ‘Take the thyroid, which is a very iodine hungry organ. With radioactive iodine the body doesn’t know it’s a potential problem; it can’t say to itself ‘this is radioactive iodine, I don’t want this.’ All it knows is that it’s iodine and it gets stuffed into the thyroid. The reason why there have been so many thyroid cancer and other thyroid malfunction problems following Chernobyl is because immense quantities of iodine-131 and its precursor tellerium-132 were emitted in the early hours of that accident.’
The high rates of childhood leukaemia around the Irish Sea coast can be understood in a similar way. Plutonium and uranium, for instance, have a high affinity for bones, and strontium latches onto chromosomes.
It must be ‘population mixing’
Official bodies like COMARE explain the excess cancers around Sellafield as a result of ‘population mixing’.
‘The hypothesis’, says Bramhall, ‘is that when you have construction projects or industry fl owing into remote areas, which Sellafield is, the construction workers bring with them a rare virus that the local population has no immunity to, and that childhood leukaemia is a rare response to this virus.’
To microbe-phobics it may sound plausible. However, the theory, first postulated in the late 1980s in response to the Sellafield clusters, has little credibility, since the virus has never been named or identified, or demonstrated to actually cause childhood leukaemia.
When compared to the mystery virus theory, the views of Busby and Bramhall on how low level radiation spreads through communities and how it gets into and damages the body, seem both plausible and rational.
They also shine a light on serious potential weaknesses in the way we determine and define the risks of radioactive pollution.
In addition to potentially underestimating cancer rates, official bodies like the International Commission on Radiological Protection (ICRP) also largely ignore the non-cancer effects from radiation that have been observed in people exposed to x-rays, in Hiroshima survivors and in populations exposed to nuclear accidents such as Chernobyl.
These include higher infant mortality, more birth defects, miscarriages and stillbirths, more heart disease, cognitive abnormalities in children irradiated in utero, and chronic fatigue syndrome.
The ICRP also fails to consider the synergistic reactions that radionuclides may have with other substances, such as chemicals that may already be weakening cells’ repair mechanism, or with damaging aspects of lifestyle such as smoking. And yet this ‘big picture’ understanding would seem necessary to fully appreciate how risky it might be to have a nuclear facility as your neighbour.
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This article first appeared in the Ecologist June 2006