Chapter 1. Linking environment and health: Introduction

The environment, which sustains human life, is also a profound source of ill health for many of the world’s people. In the least developed countries, one in five children do not live to see their fifth birthday – mostly because of avoidable environmental threats to health [1]. That translates into roughly 11 million avoidable childhood deaths each year. Hundreds of millions of others, both children and adults, suffer ill health and disability that undermine their quality of life and hopes for the future. These environmental health threats – arguably the most serious environmental health threats facing the world’s population today – stem mostly from traditional problems long since solved in the wealthier countries, such as a lack of clean water, sanitation, adequate housing, and protection from mosquitoes and other insect and animal disease vectors.

Indeed:

• Contaminated water – contaminated by feces, not chemicals – remains one of the biggest killers worldwide. Lack of adequate water, sanitation, and hygiene is responsible for an estimated 7 percent of all deaths and disease globally, according to one recent estimate [2]. Diarrhea alone claims the lives of some 2.5 million children a year [3].
• Overcrowding and smoky indoor air – from burning biomass fuels for cooking or heating – contribute to acute respiratory infections that kill 4 million people a year, again, mostly children younger than age 5. The World Bank estimates that between 400 million and 700 million women and children are exposed to severe air pollution, in most instances, from cooking fires [4].
• Malaria kills 1 million to 3 million people a year [5], approximately 80 percent of them children [6]. Other mosquito-borne diseases, such as dengue and yellow fever, affect millions more each year and are on the rise, prompting the World Health Organization (WHO) to declare the mosquito “Public Enemy Number One” [7].

What’s more, in many newly and rapidly industrializing regions of the developing world, the populations are in double jeopardy, facing both this unfinished agenda of traditional environmental health problems as well as emerging problems of industrial pollution. Cottage industries, such as backyard tanneries, can place workers and residents in direct contact with hazardous chemicals. In those areas where the use of pesticides and other agricultural chemicals is increasing and safeguards are lax – or risks poorly understood – high exposures can ensue, leading to acute poisonings and even death. For countries in the early stages of development, both pesticides and feces may contaminate drinking-water supplies, and air pollution may stem both from traditional biomass fuels and industrial use of fossil fuels [8]. Such problems are increasingly pronounced in the slum settlements that ring many of the world’s cities.

Problems can be particularly acute where economic growth is extremely rapid. In many of the most rapidly developing countries in Asia, industrialization is occurring at triple the pace of the industrial revolution in the West [9]. Many of those regions are also experiencing industrial pollution on a scale not seen in the developed world for the past 40 years – not since the London fog of 1952 caused some 4,000 excess deaths in the weeks subsequent to the episode [10]. According to the United Nations, 13 of the 15 cities with the worst air pollution in the world are in Asia [11]. A recent World Bank study estimates that more than 2 million people die each year in China alone from the effects of air and water pollution [12].

In the world’s wealthiest regions, such as Europe, North America, and Japan, although environmental risks overall tend to be lower, they have by no means disappeared.

• Asthma is rising dramatically throughout the developed countries, and environmental factors appear to be at least partly to blame.
• Millions of people in Europe and North America are still exposed to unsafe air, and some air pollutants are proving more recalcitrant to control than many expected.
• Meanwhile, biological contamination is by no means a thing of the past, as shown by the 1993 outbreak of Cryptosporidium in the United States.
• The extension of travel and trade is providing new opportunities for the spread or re-emergence of infectious diseases. In the past two decades, some 30 “new” infectious diseases have emerged [13].

In all regions of the world, populations face the threat of climate change and other global environmental problems, such as stratospheric ozone depletion. Worldwide, fossil fuel emissions continue to rise, bringing with them the risk of climate change and both immediate and long-term health effects. However, it is important to note that although the activities that are driving these changes, such as intense fossil fuel consumption, have largely been concentrated among the wealthiest nations, the impacts are likely to be greatest in the poorest regions that do not have the resources to adapt to them [14]. Similarly, in the wealthiest countries, disadvantaged populations often endure the highest exposures and have the fewest resources to deal with them.

As these examples reveal, despite considerable progress in addressing environmental problems, environmental degradation still poses a huge threat to human health in many regions. The exact nature and scale of environmental risks to health vary dramatically according to where and how one lives. The distribution of risks reflects a number of factors, including the level of socioeconomic development, distribution of wealth, a region’s geography and climate (heat and humidity are major killers), and equally important, policy choices and investments. (The regional breakdowns used in this section and in calculating the WRI indicators that follow are described in Demographic Regions Used in this Report.

References and notes

1. World Health Organization (WHO), Health and Environment in Sustainable Development: Five Years After the Earth Summit (WHO, Geneva, 1997), p. 1.

2. Christopher J. L. Murray and Alan D. Lopez, eds., The Global Burden of Disease: Volume 1 (World Health Organization, Harvard School of Public Health, and The World Bank, Geneva, 1996), p. 311.

3. World Health Organization (WHO), The World Health Report 1997: Conquering Suffering, Enriching Humanity (WHO, Geneva, 1997), p. 15.

4. The World Bank, World Development Report 1992: Development and the Environment (The World Bank, Washington, D.C., 1992), p. 53.

5. World Health Organization (WHO), The World Health Report 1997: Conquering Suffering, Enriching Humanity (WHO, Geneva, 1997), p. 15.

6. World Health Organization (WHO), Health and Environment in Sustainable Development: Five Years After the Earth Summit (WHO, Geneva, 1997), p. 136.

7. World Health Organization (WHO), The World Health Report 1996: Fighting Disease, Fostering Development (WHO, Geneva, 1996), p. 48.

8. Kirk R. Smith, “Development, Health and the Environmental Risk Transition” in G.S. Shahi et al., eds., International Perspectives on Environment, Development and Health (Springer Publishing Company, New York, 1997), pp. 51-62.

9. Nicholas D. Kristof, “Across Asia, a Pollution Disaster Hovers,” The New York Times (November 28, 1997), p. A14.

10 . World Health Organization (WHO), Health and Environment in Sustainable Development: Five Years After the Earth Summit (WHO, Geneva, 1997), p. 159.

11. Nicholas D. Kristof, “Across Asia, a Pollution Disaster Hovers,” The New York Times (November 28, 1997), 9.

12. The World Bank, Clear Water, Blue Skies (The World Bank, Washington, D.C., 1997), p.

13. Anne E. Platt, “Infecting Ourselves: How Environmental and Social Disruptions Trigger Disease,” Worldwatch Paper 129 (Worldwatch Institute, Washington, D.C., 1996), p. 6.

14. James P. Bruce, Hoesung Lee, and Erik F. Haites, eds., Climate Change 1995: Economic and Social Dimensions of Climate Change (Cambridge University Press, Cambridge, U.K.,1996), pp. 97-99.