Preface

The first United Nations Conference on the Human Environment took place in Stockholm from 5–16 June 1972. It received huge attention internationally and produced a final declaration which “having considered the need for a common outlook and for common principles to inspire and guide the peoples of the world in the preservation and enhancement of the human environment” proclaimed 26 principles. These were carefully considered high-level objectives which have undoubtedly influenced policy on the environment internationally, but – in some aspects and by some UN members – have been substantially ignored. Noting that this is the 40th volume of Issues in Environmental Science and Technology, we considered it appropriate to look back over the past 40 years to evaluate progress in environmental management in the context of the bold vision set out by the proclamation from the 1972 conference.

In more recent years, high-level United Nations activity on the environment has focussed very much on the atmosphere. Topics affecting the global atmosphere, and therefore requiring major international agreements, have been depletion of stratospheric ozone (the ozone hole) and global warming. In the first chapter, Martyn Chipperfield of the University of Leeds outlines progress in relation to the former topic, explaining the evidence for depletion of ozone in the Antarctic and at other latitudes, reviewing the international actions on regulation and control, and considering the future outlook for stratospheric ozone. Regarding greenhouse gases, John Sottong, Mark Broomfield, Joanna MacCarthy, Anne Misra, Glen Thistlethwaite and John Watterson of Ricardo-AEA in the second chapter provide a perspective on climate change, emissions and atmospheric concentrations of major greenhouse gases, and the related international policy actions and challenges. These two chapters provide a distinct contrast in that on the one hand the Montreal Protocol and subsequent international agreements have led to major action which is already showing benefits for the stratosphere, while on the other hand progress has been much slower in relation to the mitigation of global warming through reductions in greenhouse gas emissions.

Local air quality has been a major issue throughout the past 40 years. In developed countries, huge progress had been made in improving air quality prior to 1972 but subsequent improvements in epidemiological methods showed clearly that there were still major adverse effects on human health. In the third chapter, on Trends in Local Air Quality, Roy Harrison, Francis Pope and Zongbo Shi of the University of Birmingham review progress since 1970, both in developed countries and in less-developed parts of the world, such as India and China, where air quality remains very poor and impacts on human health are substantial. One of the very controversial pollution issues in 1972 was that of the use of lead as a motor fuel additive which led to substantial local air pollution issues, which have now been resolved in most parts of the world through the cessation of use of lead additives. In the fourth chapter, Robert Mason of the University of Connecticut examines the environmental presence and behaviour of two toxic metals: lead and mercury. Mercury was a major source of concern as early as the 1950s through contamination of the marine environment and the toxicity of contaminated fish. Mercury pollution remains a concern, although now more in relation to emissions to the atmosphere from sources such as coal combustion. The chapter makes it clear how regulation has tightened substantially over the period considered.

Some of the most recognised environmental problems at the time of the 1972 Stockholm Conference related to the presence of persistent organic pollutants, such as the organochlorine pesticides, as residues in the environment. The phenomenon of eggshell thinning and chick mortality in raptors and oceanic birds was brought to public attention by Rachel Carson's classic book Silent Spring published in 1962. In the fifth chapter, Mohamed Abdallah of the Universities of Birmingham and Assiut describes the most important persistent organic pollutants, their behaviour in the environment, temporal trends and future scenarios. This is clearly an area in which international action has been quite effective, but because of the very long environmental lifetimes of the compounds, many problems still remain. In the sixth chapter, Shane Snyder and Tarun Anumol of the University of Arizona consider emerging chemical contaminants. This classification includes both new industrial chemicals and substances which have been in use for many years but for which problems have only recently been recognised. The chapter considers, in particular, pharmaceutical and personal care products, perfluorinated compounds and endocrine disrupting chemicals. The importance of ever-improving analytical techniques is highlighted and consideration given to the implications for water sustainability.

One of the other major changes over the past 40 years has related to the management of solid waste. From a situation in which solid waste was seen as material to dispose of (and forget), the emphasis has now changed to re-use, recycling and waste-derived products. In the seventh chapter, Ian Williams of the University of Southampton explains the trends in waste management and examines some of the current practices designed to make optimal use of materials previously considered simply as waste for disposal. In the final chapter by David Taylor of WCA, progress in the management of effluent discharges to the aquatic environment is considered. In the 1970s, the quantities of effluents discharged to water courses frequently far exceeded the natural purification capacity of the waters; this chapter explores some of the associated problems and the solutions that have been arrived at through improved effluent management.

In its totality, this volume tracks much of the progress in management and enhancement of the human environment over the past 40 years. It is a very mixed story, with many successes but also some notable failures. There are undoubtedly lessons for the future. We are grateful to our distinguished group of authors for their contributions and commend the volume to both students and practitioners in environmental science, engineering and policy as a valuable record of the progress made in many of the most important areas of environmental pollution, and as a key reference on environmental management.

Ronald E. Hester

Roy M. Harrison