The following extracts have been taken from
"Phosphorus in the environment: its chemistry and biochemistry" by John R. Van Wazer
of the Chemistry Department of Vanderbilt University, Nashville, Tennessee.
(CIBA Foundation Symposium 57, 1978.)

 [Gin Lane by Hogarth]

The unprecedented increase in the worldwide population of humans - a growth which has been underway for two centuries and has been continuously accelerating - seems to be a root cause of many of the problems of today. Current events once more arouse fears that the probable conclusion of our present growth era will unfortunately consist of widespread death from famine, pestilence, and social disruption of various kinds.

As part of the numerous large-scale changes that we humans have introduced into our lives during the past 100 years there has been a growing worldwide use of plant fertilisers obtained from mining or chemical operations or both. A key mineral-based constituent of fertilisers is phosphorus which is one of the three elements (nitrogen, phosphorus, and potassium) that are emphasised in fertiliser technology. Phosphorus is concentrated in relatively few large deposits that may be mined and used commercially without an unreasonable demand for labour or energy resources. Most of this phosphate rock ends up in fertilisers; and deposits that appear by present standards to be economically feasible to mine are expected to last for the next few hundred years.

Because of its central role in both photosynthesis and the metabolism of all known forms of life, phosphorus is a key element for all life on earth. In view of the large and rapidly growing population of the world, many optimists look to a greatly increased use of chemical fertilisers as the means whereby the vast hordes of mankind expected in the next 25-100 years will be enabled to feed themselves.

It has sometimes been implied that a combination of chemical fertilisers, new strains of food plants with improved yields, and the continuation of 'high technology' based on abundant supplies of energy and water will allow nearly everyone in the so-called 'developing' regions to be well fed and to enjoy consumer products such as are now available to the moderate-income inhabitants of the technologically advanced countries.

On these assumptions, careful use and conservation of the easily mined phosphorus deposits could become a sacred trust for the future teeming generations.

In brief, this trust might be embodied in a proposal for mining no more phosphate rock than is necessary for sufficient food production and using it in such a way that dissipation of phosphorus into run-off waters is minimised.

Although the above scenario for the future is not impossible, it seems unlikely, being based on a delusion of grandeur that was common currency in the second quarter of the 20th century, when the media often reflected a science-fiction view of unlimited future aggrandisement for mankind. The present-day emphasis on an ecological scheme in which the human has his niche, with natural limitations for all creatures, seems to be a healthy anodyne to that recent wave of undue arrogance. The importance of chemical fertilisers to the future of mankind depends very much on the availability and apportionment of energy in the future.

People living in areas of high population density can exist in long-term equilibrium with the land without appreciable ecological damage; but a rapidly growing population has little chance of attaining this state because of ceaseless struggles to support the newcomers.

The rapidly growing poorer countries cannot possibly fulfil their aspirations for 'development' while maintaining their present birthrates.

In any event, soil erosion and other factors converting arable lands into wasted areas continue relentlessly while more and more supporting territory, such as swamps and forests, are converted into farm-land. The problems of soil erosion and other forms of land degradation are not restricted to the developing countries. The USA and Canada in their role as providers of food for the rest of the world are experiencing erosion of the soil by water and wind at a much higher rate than is at all consistent with permanent agriculture.


Neither technology nor our available resources can continue to cope with the increasing population for long. Indeed, it seems ethically undesirable to supply other than locally grown foodstuffs to feed the additional 100 million mouths that are produced each year by our fertile species, since it seems foreordained that a continued increase of the food supply without a halt in population growth will result in a vast increase in death and suffering when the time inevitably comes that food requirements can no longer be met.

This time may nearly be upon us, since it is claimed that roughly one quarter of the people in the world go to bed hungry each night and more than that number do not receive adequate nourishment. Since few people in the countries having high rates of population increase appear to realise their predicament and no one seems able to ameliorate it, it appears likely that excessive human fertility will be conquered only by famine, pestilence, war, and/or general disruption or disintegration of society.

In view of these speculations about the future, what attitude should be taken with respect to the use of phosphorus? In the long-term, whatever is done about the use of phosphate rock is unimportant; in the short-term, it seems advisable for the good of all mankind (regardless of race, country or economic status) not to support population growth by any means (including phosphate-based fertilisers) in geographical areas where little or no attempt is being made to check this growth. Likewise, phosphorus chemicals should not be used to support over consumption, so that the environment need not be degraded frivolously.

 [Bonsai tree]

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