The sustainability transition: a new challenge.

As several of the papers in this special issue show, environmental health hazards are currently most prevalent in developing countries at the household level. Among the commonest hazards are indoor air pollution, arsenic and infectious agents in drinkingwater, and local environmental exposure to lead. Finding ways to reduce these risks more quickly remains an important item on the global agenda because of the significant burden of disease they impose. At the United Nations Conference on the Human Environment in 1972, much of the concern was about chemical contaminants, the depletion of natural resources, and urbanization. This reflected problems resulting from rapid industrialization in the West and the Soviet bloc countries, as well as uncontrolled agricultural and industrial expansion in the newly independent developing countries. Earlier there had been serious episodes of air pollution, such as the London fog of 1952, organic mercury poisoning in Minamata, Japan (disclosed in 1956), accumulations of heavy metals (especially lead and cadmium), pesticide toxicity, and exposures to environmental ionizing radiation. Similar toxicological hazards persist today. Since 1972, we have had the major accidents of Bhopal, Seveso and Chernobyl, and it is highly probable that there will be more. Meanwhile, a further set of large-scale environmental problems has emerged and moved towards centre-stage. They add up to the conviction that we are living beyond the Earth’s means, and that the continued increase in human numbers and economic activity poses a serious problem for theworld as a whole. In September 1999 the United Nations Environment Programme (UNEP) issued its Global environment outlook 2000, whose final chapter begins as follows.