It is possible to produce environmental assessments in an efficient, economical manner by the careful advance specification of future information needs, the collection of the pertinent data into a single set of sectoral reports, and subsequent analysis of the information on a case-by-case basis as individual projects arise. The procedure for this, in six main steps, can be as follows:

A development scenario is produced that is a description of the chronological sequence of economic, industrial, and agricultural, activities. The scenario is studied to identify potential issues and conflicts. A list of basic questions and more specific sub-questions that follow from the issues and conflicts is then derived. The data to answer those questions are then collected and organized into sectoral reports. Later, as each assessment need arises, these sectoral reports will be found to contain the information that is required. Finally, the assessment is produced from the sectoral reports and leads to a decision on which action is taken.

The mechanics of the above procedure include: surveys of a wide range of information sources, each survey using sources which are appropriate to the step that is being taken; use of a standing core assessment group; use of common base-maps and formats; and well-planned interdisciplinary meetings.

As well as producing assessments at short notice, the procedure can be expected to provide priorities for research, and eventually to lead to due insertion of environmental considerations into national planning during the planning stage itself.

The attempt is made here to provide an approximation of the number of people that the world can support in the light of three constraints: (a) provision for a standard of living adequate for the health and well-being of everyone, (b) consideration for wildlife and Nature, and (c) reliance on existing levels of technology and politics. In fact, two alternative standards of living are suggested, ‘affluent’ (based on the standard of the 27 richest nations in the world) and ‘austere’ (based on the standard of the 43 next most wealthy nations in the world).

The first of a series of meetings, sponsored by Physicians for Social Responsibility, took place in Cambridge, Massachusetts, in February 1980, to consider the Medical Consequences of Nuclear Weapons and Nuclear War. It was followed by others elsewhere and led to the horrifying convictions that (1) it is highly unlikely that any nuclear war would be ‘limited’, and (2) no effective medical response can be conceived to deal with the human damage which would result from a nuclear attack. Consequently an organization entitled International Physicians for the Prevention of Nuclear War has been established to hold further meetings and promote general enlightenment towards avoiding widespread—even global—human carnage and environmental destruction which would accompany a nuclear war involving even a small fraction of the weapons that now exist.

The atomic bomb which was exploded over Hiroshima in August 1945 is estimated to have killed 75,000 of that city's population of 245,000 and to have destroyed two-thirds of the 90,000 buildings within the city limits. It had an explosive power equivalent to 20,000 tons of TNT, whereas many of the thermonuclear devices now deployed at the ready are some 50 times more powerful than it although still far less destructive than the most devastating contemporary weapons. Consequently the world's leaders must be brought to their senses and these horrific weapons dismantled to avoid what could be ‘the last epidemic’.

The magnitude of the problem can be gauged from the fact that at present more than 50,000 nuclear warheads are reported to be deployed and ready to launch—most of them being sufficient in destructive power to dwarf the bomb that was used against Hiroshima. Sufficient nuclear devices exist outside the United States to destroy totally every major American city. Six nations are now acknowledged possessors of nuclear weapons, and there are almost certainly others to increase the degree of instability. This situation is not so much ‘unthinkable’ as insufficiently realized or even thought about—hence the failure to reject nuclear war as a ‘viable option’ in the conduct of world affairs. Medically, any treatment programmes would be virtually useless and the costs quite staggering, so prevention becomes imperative.