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Chapter 1

THE ISSUE

Can people remain healthy in a world that is sick? What sort of environment are we going to leave behind for our children? How can we exploit nonrenewable resources without harming our health? What are the realistic compromises needed between the short-term benefits of exploiting natural resources and the long-term costs to the environment and human health? How can we live in overcrowded cities without poisoning each other?

In the mountainous regions of the Andes, the Himalayas, or Ethiopia, impoverished peasants eke out their living from the land and occasionally have enough left over to sell at the market. Their farming techniques often lead to soil degradation. Sometimes they result in collective poisoning because of the misuse of pesticides. In the Amazon, families struggling to clear their little plot of land in the forest release mercury that has been locked up in the soil for hundreds of thousands of years. Through a long process, this mercury becomes toxic and finds its way into their bodies and that of their children. People in Mexico City and Kathmandu, despite their poverty or perhaps because of it, can produce enough pollution to reduce their life expectancy. In the mineral-rich regions of the Andes or India, the local mining industry provides much-needed jobs, but sometimes at the cost of poisoning the soil, which contaminates the miners' food and that of their families.

In developing countries, the longstanding environmentally harmful effects of deforestation and overgrazing are now being aggravated by the disastrous consequences of industrialization and modernization. The ecosystems suffer the combined assault. At the beginning, exploiting an ecosystem automatically reduces its resilience or ability to rebound. When that ecosystem also has to sustain a rapidly growing human population reduced to adopting basic survival strategies, the ecosystem's resilience can be lethally undermined. But even before that, a series of perverse mechanisms can be set in motion, endangering the health of populations.

The issue that ecosystem approaches to human health -- the Ecohealth approach -- address is no less than humanity's place in its environment. As Mariano Bonet, the leader of a rehabilitation project in the oldest section of Havana, puts it: "The Ecohealth approach recognizes that there are inextricable links between humans and their biophysical, social, and economic environments that are reflected in an individual's health."

The ecosystem approach to human health is tied to the overall development of ecology during the second half of the 20th century. The emergence of this discipline has influenced the thinking of physicians like Dr Bonet, but also of many other specialists, including environmentalists, urban planners, agronomists, biologists, and sociologists, both in developing countries and the industrialized world. In the beginning, ecology adopted a perspective that was largely based on the biophysical aspects of an ecosystem. In fact, some people still consider ecology as a means of restoring ecosystems to their primitive state. Faced with the reality of a global population of some 6.3 billion people that is well on its way to 9 or 10 billion within 50 years, however, it is difficult to exclude people from the ecological equation. An increasing number therefore now include human communities in the description of contemporary ecosystems.

For those with a holistic vision, humanity with its aspirations and its cultural, social, and economic universe is at the heart of the ecosystem, on an equal footing with biophysical parameters. The living and the nonliving elements of nature interact toward a dynamic equilibrium that, better managed, should ensure the sustainable development of human communities.

From Stockholm to Johannesburg

In 1972, for the first time, the environment appeared on the world's agenda at the United Nations Conference on the Environment in Stockholm. From there was born the notion of "eco-development." Then, in 1987, the Brundtland report -- Our Common Future -- introduced the idea of sustainable development as "development that meets the needs of the present without compromising the ability of future generations to meet their own needs." Although this acknowledged the role of people in environmental change, it took another five years before the connection between the environment and human health was clearly made at a major international conference.

The United Nations Conference on the Environment and Development in Rio de Janeiro in 1992 advanced the concept of sustainable development and specified the place of men and women in such development: "Human beings are at the centre of concerns for sustainable development."

Agenda 21, which the governments of 185 countries adopted at this conference in Brazil, clearly spelled out the close link between human health and the environment. In fact, an entire chapter of Agenda 21 is devoted to the protection and promotion of human health. Simply put, if people are not in good health, development cannot be sustainable. Agenda 21 highlighted the connection between poverty and underdevelopment on the one hand, and the connection between environmental protection and natural resource management on the other. This new notion captured international attention. Agenda 21 also identified the many partners involved in implementing these measures: children, women, youth, indigenous peoples, workers, farmers, scientists, teachers, business people, decision-makers, and nongovernmental organizations (NGOs).

The World Summit on Sustainable Development in Johannesburg, in August­September 2002, placed much more emphasis on the social and economic aspects of sustainable development. Health was one of its five priorities. The World Health Organization (WHO) has taken responsibility for an action plan on health and the environment. This plan deals with several issues at the intersection of health, the environment, and development, such as water contamination, air pollution, and the management of toxic substances.

IDRC's Ecosystem Approaches to Human Health program participates in this movement toward heightened concern with the links between health and the environment. This program was created at the crossroads of the development of practices in public health and in ecosystem health. The program takes a holistic, dynamic approach that evolves with the experience of its partners in both South and North who are working on development issues affecting local communities.

Ecosystem health = human health

Discoveries in health and progress in healing techniques have considerably reduced the incidence of infectious disease in industrialized countries and, to a lesser extent, in developing countries. The biomedical approach to health is based on methods of diagnosing and treating specific pathologies: one pathogen = one disease. This approach, however, does not take into account the connections between disease and socioeconomic factors such as poverty and malnutrition, and even less of the connections between disease and the environment in which sick people live. In general, the biomedical approach to human health displays the same lack of attention to the impact of cultural factors on high-risk behaviour and the particular vulnerability of certain groups.

Despite some progress, environmental factors still dramatically affect the health of many people. WHO estimates that approximately three million children die each year from environment-related causes and more than one million adults die of work-related illnesses or injuries. Between 80 and 90 percent of diarrhea cases are caused by environmental factors. In developing countries, between 2.0 and 3.5 billion people use fuels that give off smoke and other harmful substances. In rural areas, poor animal husbandry practices result in the spread of animal-transmitted diseases and resistance to antibiotics.

In many ways, traditional methods have failed to improve the well-being, health, and sanitary conditions of people living in the South. These failures concern scientists, governments, international organizations, and donor agencies. Needed are changes in programs and policies and the vision to look beyond conventional health practices. To start, we need to look beyond the biophysical characteristics of ecosystems.

Beyond the biophysical

Predicting the health consequences of the many interactions between different ecosystem components is enormously challenging. Most agree that these interactions are highly complex and, to cover more than just biophysical parameters, researchers will need to review their research methods and be open to new forms of cooperation.

The impact of environmental factors on human health -- particularly on the health of people in the South -- is now well established. In North Africa, for example, 70 percent of wild plants have a household use, either as medication or food. But despite its importance, African forestland, which covers 22 percent of the continent, lost more than 50 million hectares between 1990 and 2000. For its part, Latin America contributed 190 of the 418 million hectares of forests lost throughout the world during the last 30 years. The loss of biological diversity associated with this kind of disappearance may have direct consequences on human health since about 75 percent of the world's population uses traditional medicines, derived directly from natural sources. In the "new" urban environments, sewerage systems, where they exist, overflow with the household and industrial wastes produced by city populations that are expanding by 2 percent per year.

In this context, it is impossible to improve the environment without including the human population, with its inherent social, cultural, and economic concerns, in the management of resources (Figure 1). In fact, the more we try to stabilize ecosystems by external measures, such as irrigation, drainage, fertilizers or pesticides, the more we diminish their ability to regenerate themselves. A sectoral approach is no longer adequate: co-management of human activity and the environment is essential. This challenge requires that disciplines draw together to study the human­environment relationship.

Figure 1. The ecosystem approach gives equal importance to environmental management, economic factors, and community aspirations. Traditional methods focus more on the latter two, to the detriment of the environment (adapted from Hancock 1990).

The economy, the environment, and community needs all affect the health of the ecosystem. Focusing on just one of these factors to the detriment of others compromises ecosystem sustainability. The Ecohealth approach is thus part of the sustainable development process. It promotes positive action on the environment that improves community well-being and health. The underlying hypothesis of the Ecohealth approach is that the programs it generates will be less costly than many medical treatments or primary health care interventions.

Societies and their leaders often face a difficult choice: resort to simple, quick, and sometimes expensive means of tackling complex problems, means that sometimes fail in the longer term -- such as the use of DDT as a magic bullet to fight malaria -- or invest in socially and economically effective long-term sustainable development. To properly address the sources of environmental degradation and to work with all of the relevant stakeholders, it is essential to go beyond simple health or environmental perspectives.

Document(s) 3 of 7