Which type of energy production is friendliest to human health?

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Several chapters in this book have depicted how our insatiable demand for energy is damaging our health. Energy production impacts on our health in so many ways. We breathe small particles emitted from coal-burning power plants. Our air is also polluted by carbon monoxide, sulphur dioxide, ozone and heavy metals. The inhabitants of the Ukraine don't need to be reminded about the risks of nuclear power. Logically, one could ask, if energy production is so detrimental to our health, why bother? Are we on a path of self-destruction due to our addiction to energy?

However, it is a truism that without energy no modern-day society could function at all. Horses cannot turn the wheels of industry. Modern-day man could scarcely survive in a purely agrarian society without access to any labour-saving machinery. His chance of survival would be minimal, about the same as the blue fox "liberated" into the wild by activists. Agrarian societies are no paradises – this is evident from the doubling in life expectancy which has occurred during the past two hundred years.

Different problems

It is difficult to understand, let alone compare, the risks of the various forms of energy production since they are so different from each other. Coal-fired power generation exerts most of its detrimental effects due to the emission of small particles. Over the long term, burning of fossil fuels leads to release of greenhouse gases and contributes to global warming. We should not overlook the health problems of one sub-group, the coal miners who have to dig the coal out of the ground.

The health risks of hydro-electric power are related to disasters, e.g. a dam bursting releasing a deluge drowning anyone in its path. The risk associated with wind power is largely related to the manufacture of the materials used in the wind turbines. Nuclear power carries two health risks; the first related to mining of the uranium ore, the second to release of radioactive material if there is an accident. Solar power is not risk-free. The material used in the solar cells is rather toxic and therefore there is the problem of disposing of the old solar panels. Therefore, if we want to compare the health risks of the different types of energy production we have to take the long-term perspective – the so-called life-cycle approach.

Everyday consequences or worst-case scenario?

For at least the past thirty years, society has been debating the question, which is safer – nuclear or coal-fired power generation and under what circumstances? Burning fossil fuels has widespread effects, but if there is an accident at a coal-fired power station its effects are localized, affecting only the people living close to the plant. In contrast, both experts and the general public agree that the problem with nuclear power is what happens should a serious accident occur. Therefore, we have to find some way to compare the day-to-day risks associated with combustion of fossil fuels to the risk of a once-in-a-lifetime disaster at a nuclear power station. Recently, sufficient data has accumulated to permit a relevant comparison to be made.

The risks associated with an accident at a nuclear power plant can be extrapolated from the data gathered after the Chernobyl disaster. Chernobyl was truly the worst-case scenario; a large proportion of the nuclear fuel was released into the atmosphere, first during the initial explosion and later in the fire which burned for many days. This kind of fire cannot occur in water-cooled reactors since they do not contain graphite which is a combustible material. Therefore, in nuclear plants with water cooling systems, a Chernobyl-like fire spreading the radioactivity widely should not occur after an explosion. Furthermore, modern-day nuclear power plants are also equipped with an explosion-proof protective shield.

The legacy of Chernobyl

About thirty of the Chernobyl nuclear power station workers and the rescue personnel were killed during the actual disaster. The release of radioactive iodine is believed to have affected almost five thousand children who developed thyroid cancer, though less than 1 % of these have been fatal. There may be a few more deaths but no huge change in the incidence is to be expected any longer. It is difficult to calculate the number of deaths from other forms of cancer due to Chernobyl and no way to identify individual cancer cases due to the disaster, and no well executed epidemiological study has been able to demonstrate increases in other cancers that could be related to the accident.

Every year there are hundreds of thousands of cancer deaths in Ukraine, Russia and Belarus (the countries worst affected by fallout from the disaster), independent of the catastrophe in Chernobyl. It has been estimated that about twenty thousand cancer deaths may be traced to the catastrophe, with these being spread over a fifty year time scale (i.e. several hundred every year). In reality, most of the cancers have probably already taken place, occurring five to fifteen years after the accident, but even then, they are only a small fraction of all cancer deaths in these countries. In this respect, it is impossible to estimate with any degree of accuracy their actual numbers.

Now, we must compare these figures to deaths linked to combustion of fossil fuels. It has been estimated that every year about three hundred thousand people die prematurely throughout Europe due to inhalation of small particles. This means that every year there are more deaths attributable to combustion of fossil fuels than total deaths linked to Chernobyl over a fifty year time scale. In fact, even should there be a Chernobyl-type disaster every year, it would not kill more people than those dying due to inhalation of the particles released after combustion of fossil fuels.

There are two arguments against such a simple comparison. First, it is difficult to pinpoint which small particles are generated by power plants and which are emitted by cars, trucks and buses. Work is going on to clarify this situation, but the initial estimates are that slightly over half of the deaths are attributable to the particles generated by traffic.

The other argument is that the deaths are not truly comparable. Deaths due to small particles generally occur in the elderly and in individuals suffering cardiovascular or pulmonary diseases; individuals who even without exposure to the particles would not have long to live. This is partly true but it would be a gross over-simplification to say that small particles only affect the sick and elderly; work is being done to evaluate which sub-groups of the population are most at risk. For example, there is evidence that infant mortality can be associated with exposure to small particles. Furthermore, most deaths occurring after a nuclear accident would be radiation-induced malignancies, and cancers develop slowly over many years. In fact, many forms of cancer can really be viewed as late-age diseases.

A comparison of sorts

The above comparison illustrates the problems faced by health experts if they are asked to weigh the pros and cons of different types of energy production. There is no unequivocal answer, but on the basis of current evidence, it is possible to come to some kind of conclusion. If impact on human health is to be the decisive factor, then the rank order (from worst to best) would be as follows:

coal >> oil >> renewables > natural gas/nuclear power

Coal is the most damaging, and natural gas and nuclear power are the least detrimental. One word of caution has to be inserted here - these estimates are based on current data and new techniques and technologies may lead to lessening of future risks. For example, emissions from a coal-powered power plant built in the 1950s (and thus their impact on human health) are very different from a new power station equipped with 21st century technology to minimize emissions. There is an ever-present risk of explosions with natural gas, especially if the pipelines are neglected and equipment not maintained. Thousands of people have died in catastrophes due to explosions of natural gas leaking out of pipelines.

One further reservation; these comparisons and the rank order do not take into account future scenarios, the most obvious being global warming and climate change. As is shown in a separate chapter in this book, estimating the impact of global warming on human health is by no means straightforward. However, inclusion of this factor would further tip the scales away from fossil fuel-based energy production.

Even though all of the current forms of electricity generation have potentially detrimental effects on human health, there are rather large differences between the various energy production types. It is clear that decreasing our dependence on fossil fuels would benefit our health as well as being environmentally-friendly.

One level up: How to protect our common environment?

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