You will notice the dolphin photo as background to my slides. This is clearly an icon of the environmental movement, and I regard myself, like most New Zealanders, as an environmentalist. It is just that I see myself as a rational environmentalist. I am not about to begin a diatribe against conservation or environmentalism. My opposition is directed at those who distort their thinking with superstition, dogma and ideology, while ignoring good science.

     How does one become a rational environmentalist? To do this, one must base one's environmental beliefs and actions on hard evidence, based on good science. The alternative, sadly used far more often, is pseudo-science. So, what is science?

     This question is vital. If we fail to understand the answer, we cannot judge the propositions set forth by those who will lead us into nonsense. Weirdly, I spent all my years at secondary school and university, ending with a science degree, never having been told what science actually is! Since that time, I have read widely, and discussed the subject with many educated persons, trying to discover the heart of science. The is far too vast to confine in a simple definition. For this reason, I have tried to define just the centre, most important part of science – that which we cannot do without. Let me share the results with you.

     Definition of the core of science. "Science is the Art and Practice of Testing."

A scientist does three things.

1. Collects data, and checks this data for accuracy.

2. Forms hypotheses to explain the data.

3. Uses the predictive test on the hypotheses. The new idea becomes the basis for a novel prediction, which is checked by new experiments or observations. If this checking process (usually by several researchers) does not validate the hypothesis, we say, it has been falsified.

     Part and parcel of the scientist’s work is measuring, and obtaining results in the form of hard, unambiguous numbers. Respect for research results, when testing is done correctly is a mark of a good scientist.

     Skepticism is linked to this. Acceptance of new, and especially of unconventional ideas, should be arrived at reluctantly, and only after the testing and measuring process has been completed, thoroughly and competently. Junk science, and irrational environmental belief is characterized by a lack of skepticism, and a lack of proper testing and measuring.

     The word, Ecomyth, refers to errors of this type, where a dogma arises among the less scientifically exact activists. A great many ecomyths are based on a seemingly sound principle : Things that are natural are good; unnatural bad. While this is often true, it is also often quite wrong, especially from the human view-point.

     For example, the dumping of toxic chemicals is 'obviously' wrong. These substances are unnatural. A weird case history shows that this is not always the case, and warns against jumping to conclusions. Before the Sydney Olympics, an old water-filled quarry was surveyed as a possible site. The pond was heavily polluted with a wide range of toxic materials. Yet it was the home to one of Australia's most endangered bell frogs. Not only that, but it was by far the biggest population and the healthiest. It appears that the toxic chemicals were protecting the frogs against attack by chytrid fungi, which were killing off populations elsewhere. Fortunately, the people who surveyed this pond were scientifically thorough, and discovered that, polluted though it was, it was an ecological treasure.

     One of the most widespread and powerful sets of ecomyths is that of catastrophism. According to this dogma, disaster is looming, and it is the fault of Homo sapiens. There are a number of types of catastrophes.

• Population catastrophe. The human race is growing too much and will over-extend the world's resources, leading to widespread famine, disease and war. Dr. Paul Ehlich has been the guru of population catastrophism. In 1968, his book, The Population Bomb was published, in which he predicted these disasters by the mid 1970's. When that didn't happen, he wrote another book putting the disasters ahead to the 1980's, then a third, in which the 1990's would carry the can. Yet every decade, the number of the world's hungry has actually diminished and average lifespan increased. Dr. Ehlich is supposed to be a very intelligent man, but he has to be one of the world's slowest learners. A variation on this theme is psychological disaster. Experiments have shown that laboratory rats kept in crowded conditions get very stressed and aggressive. Catastrophists have claimed that this fate is in store for us, though there is not the slightest shred of evidence for this very pessimistic idea. Humans often live in highly crowded conditions. Even Auckland has a population density many times that of Bangla Desh. We are nature's most adaptable creature. We practice courtesy. Imagine you bump into someone in a crowded mall. Is there aggression or stress? No. Just a rapid apology, and you move on.

• Ecological Catastrophe. We are wiping out the world's greatest wild habitats, and causing millions of species to become extinct. The trouble with this concept is that the evidence is just not there. There is still more relatively untouched wilderness than there is land exploited by people. And that does not count polar regions or deserts. Extinctions are dreadful tragedies. However, millions??? A common mis-belief is that habitat loss is the prime cause of extinctions. The example of the Caribbean island of Puerto Rico shows how wrong this can be. Once, the island was covered with rainforest. 60 native birds, found no-where else, lived in the untouched wilderness. Then came man. 99% of the forest cover has been destroyed, though about 15% has re-grown. Only six of the native birds became extinct, and ecologist Dr. Ariel Lugo (who carried out the major survey with the US Department of Agriculture) thinks they died due to the introduction of rats – not habitat loss. Indeed, the main cause of extinctions world-wide is the introduction of alien invaders, like rats or stoats, into an environment unprepared for them.

• Genetic catastrophe. Genetic engineering.

• Climate catastrophe. The world's climate is getting hotter. The world's climate has always been warming or cooling.

• Ozone depletion catastrophe, and increase in cancer causing ultra violet. So far, all the increase in ultra violet is equivalent in its impact only to that which would happen if you moved from living in Wellington to living in Auckland.

     And so on, and so on, and so on. But why is all this nonsense a problem? Why not just let people live with their superstitions, if it makes them happy?

     The real problem is that acting on beliefs that lack any scientific basis often hurt people and even kill them in large numbers.

     In the late 1960's and early 1970’s certain environmental groups, including Greenpeace decided that chlorinating water was a bad thing. This was based on the discovery that chlorine reacted with organic compounds to make carcinogens. However, they ignored the fact that such toxic materials were made in only the most minute quantities – far too little to cause the slightest harm to anyone. Based on their inadequate science, they set out to persuade authorities to stop chlorinating water. The government of Peru was one that listened. The result was, in 1971, an outbreak of cholera, made much worse by lack of chlorination, that killed 7,000 people.

     Another, even more extreme example of how an ecomyth can cause dreadful harm is the sorry story of DDT. This insecticide is very powerful, and is harmful to the environment if used irresponsibly. It is slow to degrade (50 year half life) and is bioaccumulative. However, the greatest criticism came in Rachel Carson's influential book Silent Spring. She stated, using extremely weak evidence, that DDT killed wild birds by thinning egg shells, and that it caused cancer in humans. Using the predictive test ("I predict that if I feed cage birds DDT, their egg shells will be thin."), scientists have falsified the first idea. Epidemiologists following up on World War II veterans, who had been doused in DDT powder to kill lice, found no link with cancer. Both claims are wrong. Yet these two claims led to world wide bans on DDT. Does this matter? Yes!

     DDT is the best weapon yet discovered against malaria, which still, in the 21st Century kills two million people each year – mostly young children. In earlier years, it was even more destructive. DDT kills the Anopheles mosquito which spreads the disease. In Sri Lanka, 1948 was a bad year, with nearly 3 million deaths. Then DDT was introduced. By 1964, the death toll was 17. Then DDT was banned. In 1969, deaths had risen to 2 million. One estimate is that the bans on DDT have killed 60 million people unnecessarily.

     DDT is still nasty, and has to be used with care. Fortunately, there is a way. Broadcast spraying is out. Instead, it has been found that all we need to do is spray the inside walls of people’s homes (or mud huts). Cost is $2 per year. This gives almost total protection. South Africa is now using this method to dramatically reduce malaria deaths.

     Let me tell you of a scientific principle which is highly relevant to much of the eco-nonsense. The principle of Hormesis. You will have heard from various radical greens that minute amounts of harmful materials such as dioxins, pesticides, nuclear waste, and industrial chemicals cause cancers or other harms. They have their own model of reality involving a simple linear relationship, starting from zero, between dose and harm caused. In other words, as contact with the harmful agent reduces, so does the harm. But the harm is always there, until we reach zero dose.

     The classic scientific model, based on failed attempts to prove that small doses cause harm, is an exponential relationship. No harm done, while the agent’s dose increases, till it reaches a minimum harmful level. From there, the harm increases exponentially with dose.

     However, an increasing amount of scientific data now suggests a third, and very surprising model may be the correct one. This is termed Hormesis. At low levels, harmful agents actually stimulate the body to build up their defenses, leading to greater strength and vigour.

     How does this give the lie to many pseudo-scientific claims?

     For example, after the tragic Chernobyl incident, Greenpeace claimed, on the basis of their flawed model, that the radiation released would lead to an extra two million deaths from cancer in Sweden alone. The standard scientific model would suggest no new deaths, since the dose would be too low to be harmful. However, the Hormesis model would suggest that the low dose would actually stimulate our defenses against cancer and lead to a reduced incidence and a lowered mortality.

     There is a great deal of evidence to support this idea. Professor John Cameron was contracted by the American military to investigate possible harm to nuclear ship builders. Including a control group building non nuclear ships. A total of 71,000 people were tested. Result : workers on nuclear ships, exposed to much higher than normal radiation, had a reduction compared to control of early death of 24% - highly significant statistically. This result has been confirmed by at least three other studies I am aware of.

     Similar results have been obtained with chemical toxins. The most poisonous man-made substance is a dioxin called 2,3,7,8 TCDD. Early studies on laboratory mice showed that, at very small doses, it caused cancer. This has been used by Greenpeace and others to attack industries (like pulp and paper) that release dioxins, albeit at extremely low levels, into the environment. What they failed to note, is that the same experiments showed that mice exposed to even smaller doses, actually had statistically significantly lower rates of cancer than control groups. Very small doses of this dioxin actually protected against cancer! If we measure the levels of dioxins we, and the natural world, are exposed to, we discover that, if anything, levels are too low. They are way below that needed to cause harm, and are several orders of magnitude too low to exert their protective effect.

     Sadly, the dogma ridden ecological activist is normally ignorant of and unaware of the importance of numerical data. Anything harmful released into the environment must cause harm regardless of quantity. They are fond of the mantra "dilution is not the solution to pollution." In fact, the opposite is true. Dilution is usually the best solution to pollution. We fail to note that our everyday world is filled with toxins and radioactive substance, in small doses. Just the soils in New Zealand contain millions of tonnes of arsenic.

     It is totally harmless due to the extreme dilution. Human release of arsenic to the environment will always be tiny compared to what is already there. The same principle holds for the majority of pollutants.

     Pollution, therefore, is a local phenomenon. It is very harmful when concentrated. Not so, when dispersed. How many people have heard the phrase "polluting the oceans?" This is, in fact, impossible. Do the sums. The oceans of the world contain approximately 10¹8; tonnes of water. One million times one million times one million. If we were to dump a million tonnes of any pollutant in the ocean, and disperse it, the final concentration would be one part per trillion. Even for the most toxic chemical ever made by man, this dose is totally harmless to anyone or anything. However, concentrating a toxic material in a harbour or bay may cause local disaster.

     The New Zealand Labour Government has suggested that the main reason we could not ever contemplate nuclear power is the recalcitrant problem of nuclear waste. In fact, the major problems of nuclear power are political and economic. Nuclear waste is the easy one. Before the collapse of the iron curtain the Soviets disposed of some of their nuclear waste by dissolving it in acid, diluting massively, and pumping it into the Arctic Ocean. Imagine the horror of Americans when they were told this by their new-found Russian friends. A research team was dispatched to measure the environmental damage. In fact, they found none.

     When we do the sums, we find that this is not surprising. The total amount of radioactive elements produced as nuclear waste, by all the power stations in the world, each year, is about 100 tonnes. The oceans of the world contain about 50 million tonnes of radioactive Uranium 235. If we were to dissolve all the world's nuclear waste for the next thousand years and disperse it through the oceans, we would be struggling to measure the increase. It would certainly do no harm whatever.

     Nevertheless, real environmental problems do exist. In New Zealand, there are two main ones.

• The problem of alien invaders. Stoats, rabbits, possums, rats, wild ginger, fungal plant diseases and many more. Preventing any more such disasters (Bio-security) should be high on the priority list of any government.

• Lack of re-forestation. We see enormous fuss made whenever a few acres of our rain forest habitat is threatened. Yet this is trivial. Much more important is the fact that literally millions of hectares of this forest was removed in decades past. The bare land is now dumping millions of tonnes of soil into rivers and the sea each year, and slowly strangling marine ecosystems over hundreds of thousands of square kilometers. We desperately need to plant trees over the areas affected and stop this degradation.

• Pollution and nutrient enrichment (such as in Rotorua lakes) is a serious problem, though less so than the first two.

     In spite of the continuing existence of these problems, I am an environmental optimist. 21st Century New Zealanders are devoting more and more time, money and effort into fighting these problems. The worst pollution and de-forestation happens in poorer nations. And the world is getting richer. As third world nations become wealthier, they too, will work to improve the natural environment. We can look forward to longer lives, higher standards of living, and very much improved environmental care.