Thematic of the 2004-2005 Ecohealth Awards: Using Ecosystem Approaches to Human Health in Urban Settings
Addressing the environmental and human health problems posed by urbanisation is an increasingly important challenge in most regions of the globe and is essential to successfully address poverty alleviation. Urban citizens are exposed to a wide variety of biological, physical, chemical, political hazards, and it is increasingly clear that their health is undermined by negative environmental conditions, especially those that prevail among the widely-distributed poorer sectors of society. In such a context, a key challenge for improving community health is the development and implementation of a holistic approach that can foster a better understanding of the interplay between multiple factors influencing human health in urban settings. One such approach is an Ecosystem approach to human health. Ecosystem Approaches to Human Health (also referred to as Ecohealth) start from the premise that the health of the human population is shaped by a range of factors including the living and working environment, socio-economic organization and community lifestyles, and suggest that better management of the ecosystem can therefore contribute to improving human health. Ecosystem approaches seek to better comprehend the interaction between various components of the ecosystem (biophysical, social and cultural), and how these components influence the prevalence of health problems among human populations. In this context, more efficient ecosystem management strategies that contribute to improving the health and life conditions of human populations, and the sustainability of the ecosystem in which they live, may be identified. (Forget & Lebel, 2001). Ecosystem approaches promote a holistic view of human health and environmental sustainability, and rely on a trans-disciplinary framework and participatory and social/gender sensitive methodologies. For further information on Ecohealth, please visit the website www.idrc.ca/ecohealth.
The urban ecosystems: The first challenge for exploring the potential of ecosystem approaches to human health in urban settings relates to the need to define an “urban ecosystem”. Broadly speaking, an ecosystem is a dynamic complex of interactions among living organisms (including humans) and non-living factors, in a given area, where energy and matter are either produced, consumed, or released. The boundaries of ecosystems often have more to do with the parameters that humans set deliberately according to the scientific, management, or policy question they wish to examine, rather than with biological or physical dimensions. Two main types of ecosystems, which differ in terms of matter, energy and biota, are often differentiated: natural and anthropic ecosystems. Natural ecosystems include forests, grasslands, lakes, etc., while anthropic ones usually refer to agricultural fields, cities, houses, bedrooms, 1
schools, etc., the existence of which are strongly linked to intense human activity. However, it is clear that this distinction is an artificial one. Most so-called “natural” ecosystems have been affected by human activities over time, and natural resources play an important role in many anthropic ones. There is a gradient between the two and their limits must be set according to the specific needs of a project or research question. The concept of an ecosystem also allows for the fact that within its boundaries, all living organisms have a habitat (or housing for human beings), and an ecological niche (or profession). For ecosystems where humans prevail, socio-economic activities and natural resource management as well as social and cultural factors must be carefully considered. A major flux of rural-urban migration has been occurring in the last decades due to land tenure, agricultural crisis, and one search for jobs, especially in Southern countries. It is estimated that by 2020, around 60% of the population in West Africa will be living in urban areas. In LAC, currently more than 70% of the population lives in urban areas and in 2020 it is expected that 80% will be urbanized. In all regions, the rapid urbanization process is linked to a multi-factorial set of determinants and implies major challenges for the healthy management of urban ecosystems and human health.
The urban setting and human health: Major human health problems of urban ecosystems in the South are related to poverty and degraded and deteriorating environments. $ Access to clean water is a major problem in many urban neighbourhoods in the developing world. There is a wide range of health concerns related to water conditions and availability. Enteric diseases, vector borne diseases (such as Dengue and Malaria), and critical levels of exposure to chemical pollutants (lead, cadmium and mercury) are the major categories of public health concerns. $ Lack of proper sanitation facilities and overcrowded housing typically result in increased risks of disease transmission. $ Untreated sewage usually goes to the rivers, without proper treatment, causing organic and industrial pollution. River pollution can potentially affect other human communities who rely on the river, for example for fishing purposes. $ Solid waste of domestic and commercial origin very often lacks appropriate disposal or remains scattered in the poorest districts due to scarcity of financial resources of municipalities. Health problems associated with solid wastes can be either at the site of release, or at the site of disposal, if collection is available. In any case, the combination of the unwanted biota (rats, mosquitoes, etc), increased risks of flooding or water stagnation as debris clog storm sewers and vulnerable human population can pose serious health risk conditions. Air pollution in the urban context may originate from a variety of sources, including automobile exhaust, construction, industrial activities and refuse-burning. The resultant decrease in air quality can severely impact the health of human populations (for example, their respiratory and cardiovascular systems), and sometimes, even lead to premature 2
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death, depending on the pollutants. Also related to poverty is the local informal economy of resources and services that can play a major role regarding the type of occupation and family structure in the community. In spite of the economic benefits of an informal economy, many ecosystem and human health problems can be associated with the pattern of this occupational sector and associated health risks. Commercialization of pesticides on the streets is a good example of this kind of market economy. While food vendors offer easy access to inexpensive food, they often pose important public health risks. Most regions have experienced a strong decentralization process where several functions were transferred to local governments. Cities are currently facing major governance challenges, as local capacities may not yet be prepared for this task. In addition, the decentralization process has not involved the transfer of adequate resources from the central government to cover health and sanitation costs, nor has it been followed by appropriate inter-sectoral policies. Decentralization has also failed to enhance the role of civil society at the municipal level.
One of the most visible and unfortunate consequences of inadequate development and urbanization policies is the notable increase of slums in medium and large cities. The abovementioned social and environmental threats to human health are particularly serious in large slums, where lack of basic services such as water and sanitation, education and health facilities, combine with growing inequalities, social violence and poor economic conditions. They especially jeopardize the health and future of young children. The increasing rate of geographical segregation of poverty on the periphery of cities implies an urgent demand for developing a territorial urban management approach.
Potential of ecosystem approaches to human health in an urban context: The increasing degradation of urban environments in developing countries is closely linked to patterns of development and economic stagnation in most countries. The strong interactions and interrelations of economic, social and cultural determinants present a challenge for developing a holistic understanding of environmental degradation and its impact on human health. In spite of this complexity, an Ecohealth approach provides the basis for exploring and testing participatory intersectoral policies to ensure the appropriate management of urban ecosystems. In the context of economic stagnation, poverty and deepening inequities, it is critical to understand how countries will avoid growth-degradation tradeoffs and prioritize equity in ensuring access to key urban services. Health problems associated with this myriad of exposures must be mitigated. Public health efforts need to be developed in the context of a larger urban ecosystem approach addressing interacting complex processes. The complexities of managing resources and services for human beings in urban ecosystems demand close attention to research and policy on: sanitation (including water, sewage, solid wastes and air quality); housing and transportation; environmental pollution; socio-economic and cultural aspects; health services and diseases; 3
perceptions and attitudes of communities; and formal and informal institutional domains, among many others. Submissions to IDRC’s Ecohealth awards this year should focus on the potential of using Ecosystem approaches to human health to better understand the links between human health and urban ecosystem conditions, and identify potential strategies to improve human health and the sustainability of the ecosystem, based on the better management of natural resources and social dimensions in a highly complex context. Applications should clearly detail how the proposed research will integrate the basic principles of Ecosystem approaches to human health, namely: transdisciplinarity, community participation, and social and gender sensitive methodologies.
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