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have been caused, partly at least, by man's industrial activities. What is certain is that we cannot go on systematically modifying the chemical composition of the atmosphere indefinitely. At some point in time, some positive feedback mechanism must be triggered off, causing climatic changes sufficient to transform living conditions on this planet and possibly render much of it unsuitable for human habitation.

Dispersal and dilution are thereby clearly not a means of controlling emissions of CO2, N2O, freons etc., nor of heat and dust into the atmosphere. Global atmospheric pollution by these substances can, in fact, be said to be out of control. Krypton — 85

Releases of radioactive substances into the atmosphere are also justified on the same grounds — and with no better justification. Consider the case of Krypton-85, a radioactive substance released by nuclear installations throughout the world. At Windscale no efforts are made to contain it in any way, the theory being that it will be diluted in the atmosphere in which it will only be present in harmless quantities. Dr. William Boeck,107 Professor of Physics at Niagara University and Chairman of the Krypton-85 working Group of the International Commission of Atmospheric Electricity, pointed out, at the Windscale Inquiry, what is the real fate of the Krypton-85 released in this way. According to him, it will cross England and enter the air space of other countries. Every month or so afterwards, a portion of the same Krypton-85 released will recross the UK on its way around the world. The rest will have spread to the north and south to other countries. The result of this disposal by export will be the contamination of the global atmosphere. Before there were nuclear reactors, and before nuclear bombs were used in the 1940s, the atmosphere was almost entirely free of Krypton-85. The total amount present on the land, in the oceans, and in the atmosphere was probably no more than twelve curies. The Windscale plant alone, however, will release almost fifteen million curies every year, while during its lifetime the plant is likely to introduce 230 million curies into the environment, that is about twenty million times the 318

natural background level. Imagine what would be the effect on the environment i f and when there are ten or twenty such plants functioning in the world.

According to Boeck, i f these releases continue unchecked, the background of radioactivity in the lower levels of the atmosphere must grow with a corresponding increase in the cancer rate and in the rate of mutations.

There is also the possibility that it might lead to some sort of global climate change, and in particular that it might modify global rain patterns, some agricultural areas becoming deserts while some deserts are turned into agricultural land.

It must be noted that Krypton-85 is only one of the dozens of different radioisotopes emitted into the environment in a routine manner by a growing number of nuclear installations throughout the world — and in each case, we continue to be told that they will be diluted in such a way as to become quite harmless to living things.

Exporting SO2

Sulphur-dioxide, produced by various industrial processes, also tends to be released into the environment in increasing amounts via chimney stacks. The method normally used to reduce emissions is to raise the height of the chimney stacks in such a way as to disperse this substance into the environment and hence dilute it to a point where it is no longer damaging. But is it

E .8 Uj

actually so diluted? This was answered in 1976 by a committee set up to measure the long range transport of air pollutants by OECD.108 It was found that roughly thirty per cent of the SO2 emitted in an area was deposited locally via rainfall, fifty per cent was 'dry deposited' and the balance, about twenty per cent was transported elsewhere often to other countries. In this way each country in Europe appears to be constantly importing and exporting SO2 pollution, some such as Britain being net exporters, while others like Scandinavia being net importers.

Efforts to disperse and dilute SO2 from British factories thereby leads, among other things, to the pollution of distant lands where, as in Scandinavia, it is almost certainly stunting forest growth and is known to be acidifying lakes; 10,000 Swedish lakes are almost devoid of any fish life and another 10,000 are badly affected.109

IMPORTS AND EXPORTS OF SULPHUR EMISSIONS (1) in 1974 (Dry plus wet; 103tons of sulphur)

3 Q O il l O

c CO Ql o CO Q_

Total Total received Emitted from all to all

areas areas

Total Total received Emitted from all to all

areas areas

Austria

Belgium

Denmark

300 221 Surround­

200 499 Surrounding

Surround­

Surround­

200 499

ing areas

ing areas

ing areas

areas

Federal Republic of Germany 1,250 1,964

Federal Republic of Germany 1,250 1,964 Czechoslovakia,

Finland

400 274 Czechoslovakia, German Demo­

France

1,000 1,616

The Netherlands 150 391

Czechoslovakia, German Democratic Republic, Italy, Poland and

Czechoslovakia, German Democratic Republic, Italy, Poland and

Czechoslovakia, German Democratic Republic, Italy, Poland and

German Democratic Republic, Italy, Poland and

cratic Republic, Italy, Poland and

Norway

250

91

other areas

other areas

other areas

other areas

other areas

11,000 —

11,000 —

11,000 —

11,000 —

11,000 —

Sweden

500 415

Switzerland

100

76 Total Emitted

United Kingdom 1,000 2,883(3) Total Emitted t o above areas 17,000 —

Total Emitted t o above areas 17,000 —

t o above areas 17,000 — The Dispersal of Heavy Metals

Efforts to dilute emissions of heavy metals into the environment are proving equally unsuccessful. Its advocates go out of their way to show that man's contribution to mercury, for instance, is insignificant compared to that which has accumulated naturally (15,000 tons a year for instance compared to thirtyfive million tons). This argument is a very naive one as it fails to take into account that the mercury released by man is not immediately diluted evenly throughout the world's oceans. As Anthony Tucker110 points out "i t takes tens of thousands of years for metallic marine pollutants to disperse uniformly: contamination therefore builds up in those waters into which pollutants are discharged, in this case, estuaries, coastal areas and nearby shallow continental shelf areas. Because these areas are also the most highly productive of the entire ocean, the dangers are real and immense. Relatively small quantities of contaminants can disrupt the life processes in the sea's most important areas and may already be doing so."

Oil Pollution

The argument that oil pollution is rendered harmless by dilution is equally untenable. At a recent United Nations Environment Programme (UNEP) meeting in Paris111 it was pointed out that six million tons of petroleum are dumped each year into the world's oceans. Accidents of one sort or another are responsible for another four million tons, while at least another six million tons are introduced into the seas as the unburnt residue of diesel oil from ships' funnels. The French paper Le Monde?7 however, recently pointed out that this is nothing when compared with the total volume of water contained in the world's oceans — roughly 1018 tons or 1.4 billion cubic kilometres. The ratio between these masses of oil and water is equal to 1011 , which means that the mass of oil discharged into the sea every year is only one hundred-billionth of the mass of water.

But this is irrelevant, because to quote a UNESCO report "petroleum is made up of hydrocarbon molecules which are hydrophobic — i.e.

The Ecologist Vol 9 No 10 Dec 1979

Mercury accumulated in a pool at a

nitrogen factory in Japan

insoluble in water and remain concentrated on the surface. But petroleum always contains between five and ten per cent of oxydised molecules or organic detergents containing oxygen, which are semi-absorbent and penetrate into the water by their oxygen-bearing extremity. . . The American physicist Irving Langmuir has shown that these semi-absorbent molecules spread out to form an extremely thin layer onto which the rest of the petroleum spreads in turn, thus creating what he calls a 'duplex layer' on the surface of the sea, whose thickness is determined by the proportion of oxygen-bearing molecules. If the ratio is five to one hundred, the duplex layer will be 400

angstroms thick, that is to say 1/25,000th of a millimetre . . .

This may seem infinitesimal, yet one cubic metre of petroleum discharged into the sea would cover twenty square kilometres of water. The total surface of the world's oceans is some 300 million square kilometres, so the ten million tons of oil discharged into the sea every year are enough to cover 200 million square kilometres or two-thirds of the world's oceans. " Biological Amplification

The principle of dilution has nevertheless been defended by some of our most distinguished experts. Sir Robert Robinson113, Nobel Laureate in organic chemistry, for instance, discounts the threat of lead pollution to oceanic plankton in a letter to The Times. "Neither our prophets of doom nor the legislators who are so easily frightened by them are particularly fond of arithmetic." He then sets out to show by simple arithmetic that the dilution of lead in the oceans would be so great that lead pollution could not possibly occur. Not only does he ignore the fact that lead would be unevenly distributed in the oceans, but he fails to take into account the workings of a phenomenon referred to as biological amplification. Clams oysters and molluscs in general feed by filtering enormous volumes of water. When doing this, they separate trace contaminants within the water and sometimes concentrate them by a very large factor. Some fresh water molluscs for instance can concentrate manganese by a factor of 300,000 and the chlorinated hydrocarbon insecticide by up to 70,000 times.

Table 2 shows estimated concentration factors for different pollutants in aquatic organisms.

Unfortunately these factors are

Estimated Concentration Factors in Aquatic Organisms

Radionuclide Site

Fila­

Phyto- mentous Insect

plankton

Algae Larvae

Table 2.

Fish

Na 2 4

Cu64

Columbia River

Columbia River

500

2,000

1,000

Rare earths Columbia River

Fe39

P 22

p 33

Sr 30 -Y 9 6

Columbia River 200,000

Columbia River 200,000

White Oak Lake 150,000

White Oak Lake 75000

500

100

500

500

500

200

100,000 100,000 10,000

100,000 100,000 100,000

850,000 100,000 30-70,000

500,000 100,000 20-30,000

100

50

100

Source: Eisenbud, 1963 (reproduced from SCEP).

319