CHAPTER 3 Ecological sustainability and human health
Concerns about the environment now include ecosystem viability and the impact this will have on human survival. Innovative responses will be required by the health sector to the projected social, psychological and physical health consequences of natural resource depletion and pollution of air, water and soil, climate change, and food shortages and changing disease patterns. Society will expect health workers to take a leading role. ‘Top down’ and ‘bottom up’ approaches will be needed. Currently the health sector is unprepared for this emerging role. This will be one of the most challenging public health issues for this century.
Chapter 3 builds on the ideas presented about the determinants of health and illness discussed in Chapter 1 and the core concepts and values discussed in Chapter 2. This chapter will present an introduction to ecological sustainability for health workers by providing: definitions and principles of ecological sustainability; a rationale for the engagement of the health sector; and case studies for health professionals working with individuals, in community settings, and as citizens playing a leading role in ensuring ecosystem viability and, consequently, good human health. Links between the physical, emotional and social health of people, the health of the environment and the implications for practice will be made.
The health of humans is dependent upon a healthy ecosystem. The Convention of Biological Diversity defined an ecosystem as a ‘dynamic complex of plant, animal and micro-organism communities and their non-living environment interacting as a functional unit’ (United Nations Conference on Environment and Development [UNCED] 1992a). A healthy ecosystem is a principal determinant of human health. On the health iceberg, presented in Chapter 1, we would place ecosystem health well below the waterline, acknowledging that the interplay between the social and environmental determinants on health and illness are inextricably linked. In Labonté’s (1997) framework of the determinants of health, also presented in Chapter 1, ecosystem viability, sustainable development and convivial communities are outlined as health-promoting conditions, while natural resource depletion, the enhanced greenhouse effect and polluted environments are located in the risk conditions along with poverty, low social status and discrimination. These are the fundamental determinants of illness.
We can promote ecological sustainability and consequently human health by ‘using, conserving and enhancing the community’s resources so that ecological processes, on which life depends, are maintained, and the total quality of life, now and in the future, can be increased’ (Australian Government 1992). Working towards ecological sustainability is consistent with Primary Health Care principles. Ecological sustainability will be achieved with consequent improvement in the quality of life of humans through social justice, intergenerational equity, employing the precautionary principle and biodiversity conservation. These principles enable us to prevent and reverse adverse impacts of human activities on the ecosystem, while continuing to allow the sustainable, equitable development of societies (see Box 3.1). The philosophy and action presented throughout this book through the Primary Health Care lens is entirely consistent with working towards ecological sustainability and health. The appendices of this book all affirm that health is a human right, is determined by the environment, both social and natural, and each provides guidance for environmental stewardship, governance, and citizen participation.
Precautionary principle ‘Where there are threats of serious or irreversible environmental damage, lack of full scientific certainty should not be used as a reason for postponing measures to prevent environmental degradation. In the application of the precautionary principle, public and private decisions should be guided by careful evaluation to avoid, wherever practicable, serious or irreversible damage to the environment and an assessment of the risk-weighted consequences of various options’ (Deville & Harding 1997: 13).
Intergenerational equity Extends the principle of fairness and justice to future generations. The principle holds that the present generation has a stewardship role in conserving the natural and cultural resources of the earth and all species so that future generations may enjoy the same quality of life as the present generation.
Biodiversity conservation ‘… the protection of ecosystems, natural habitats and the maintenance of viable populations of species in natural surroundings’ (UN Department of Economic and Social Affairs 1992). Biodiversity refers to the variety of all life on earth — plants, animals and microorganisms, as well as the genetic material they contain and the ecological systems in which they occur. Biodiversity is necessary to maintain our atmosphere, climate, water and soils in a healthy state.
There are aesthetic, cultural and ethical reasons for maintaining biodiversity. Humans define themselves through their ecosystems. It is an essential element of intergenerational equity and also, other species have as much right to the earth as humans.
The role of health professionals in addressing the looming ‘public health emergency on planet earth’ (Hales & Corvalan 2006: 130) is becoming clearer. There has been recognition of the links between ecological sustainability and health at the global as well as the local level for some time; for example, see Boyden (1987), UNCED (1992b), McMichael (1999), Brown et al (2005) and Hales & Corvalan (2006). McMichael et al (2000: 1067) suggested that ‘…our task in this evolving discourse, as health professionals, is to make clear that population health is a central criterion in the sustainability transition’. However, generally speaking the health sector in Australia has not been engaged in this conversation (Verrinder 2007).
In 2005, the World Health Organization (WHO) acknowledged that potentially, human-induced changes to the climate will threaten economic development and social and political stability and, consequently, human health (British Medical Journal [BMJ] 2005). Al Gore’s film An Inconvenient Truth, the Stern review on The Economics of Climate Change (2007) and the 2007 report by the Intergovernmental Panel on Climate Change (2007) captured the imagination of the media and raised the level of public debate globally. In 2008 the WHO declared World Health Day as ‘protecting your health from climate change’ in recognition that ‘wherever you live, climate change threatens your health’ (WHO 2008e).
Changes to the environment have always impacted on human health at the local level. Cancer, respiratory, cardiovascular and communicable diseases as well as neuropsychiatric disorders have been caused by exposure to pollutants (Organisation for Economic Cooperation and Development [OECD] 2008b). Infectious diseases such as SARS, Ebola virus, Nipah virus, Avian (bird) flu and Hantavirus have all been found to result from ecosystem change created by humans. When new diseases emerge they usually have high death rates and few known therapies (Verrinder 2003).
Changes in the ecosystem at the global level now pose different challenges. It is tempting to think of climate change as the only environmental health issue. In fact climate change is a symptom of widespread degradation and pollution of land, water and air. Changes to natural ecosystems world-wide have been more rapid over the past 50 years than any other comparable time in history (WHO 2005b). These changes are primarily attributed to human activity. We are now operating in an ecological deficit. The Ecological Footprint (Rees & Wackernagal 1995) illustrates that, as a global community, we need about 1.2 planets to meet our average resource consumption levels (Environment Protection Authority 2008). Combinations of a burgeoning population and over-consumption have contributed to enhanced greenhouse effect, resource wars and pollution. Water, soil and air, those things fundamental to our survival, have been degraded. Collier (2003) analysed 54 large-scale civil wars that occurred between 1965 and 1999 and found that a higher ratio of primary commodity exports to Gross Domestic Product (GDP) ‘significantly and substantially’ increases the risk of conflict, meaning that civil war becomes more likely when countries export commodities as a priority over local public health and nutrition needs. This is unsustainable. We need to make a long-term commitment to integrated action and the health workforce has a key role in human health protection and in supporting systems and programs based on sustainability principles.
Ecosystem and Human Well-being Health Synthesis (WHO 2005b) was produced as a result of the Millennium Ecosystem Assessment (MEA) referred to in Chapter 1 (see Box 1.2). The report is a synthesis of the evidence produced by the MEA about how ecosystem changes do or could affect human health and wellbeing (WHO 2005b). Figure 3.1 encapsulates those impacts. The figure describes the casual pathway from escalating human pressures on the environment through to ecosystem changes resulting in diverse health consequences. Not all ecosystem changes are included. Some changes can have positive effects (e.g. food production). The effects may be immediate and long-term, direct and indirect, local and global.
FIGURE 3.1 Why do ecosystems matter to human health?
(Source: Corvalan, Hales, McMichael 2005: 1) Reproduced with the permission of the World Health Organization.
Human health is directly affected by ecosystem degradation by way of floods, landslides, heatwaves, water shortages and exposure to pollutants (WHO 2005b). Floods, heatwaves and landslides are widely reported by the media because they are sporadic and usually cause large scale disruption and death. However, worldwide, 3% of all deaths and 4.4% of all years of life lost are attributed to water related disease (OECD 2008b). Beyond the challenge of maintaining per capita water supply, in the face of population growth, there is a global deterioration in the quality of drinking water (McMichael 2001). Polluted drinking water and food contribute to infectious diseases and poisoning. Toxic chemicals cause accidental acute poisoning or long-term poisoning from the residues in food. Contamination is accelerating from industrial, agricultural and domestic wastes. Man-made chemicals used in industrial and agricultural processes may cause cancer and damage nervous, reproductive and immune systems (United Nations Environment Program [UNEP] 2005). Coastlines are becoming increasingly under pressure from human waste disposal and other human activities. The spread of enteric viruses and bacteria caused by sewage disposal is now a major worldwide problem. Air pollution is also a problem in many cities, particularly in poor countries because even if health policies exist, they do not have the resources to pour into infrastructure to prevent pollution. Respiratory disorders, including asthma, bronchitis and lung cancer, are the result. Deaths from air pollution cause 800 000 premature deaths globally annually (OECD 2008b). These later examples of the health impacts of degraded ecosystems are so constant that they rarely make the daily news.
Climate variability has raised the level of public debate in recent times about the interdependence of the health of humans and the health of the planet at a global level. Global warming is a symptom of a degraded ecosystem. Until now the effects from global warming have been largely indirect. There is uncertainty about the details, magnitude, timing and health consequences for the future (McMichael & Campbell-Lendrum et al 2003). However, the heatwaves in August 2003 in Europe contributed to over 35000 premature deaths (BMJ 2005). The annual global death rate from global warming is already estimated at 60000 (Horton & McMichael 2008). It is predicted that global warming will alter ecosystems, agricultural productivity, food supply and cause resource wars. The rising salinity of water tables will damage more farmland. Inappropriate adaptation and mitigation strategies to global warming will give rise to population displacement and further livelihood loss. Heat increases due to global warming will stress and endanger the elderly, the frail and those working in high heat jobs. Heat related deaths result from increased strain on the cardiovascular system, industrial accidents, behavioural disruption and heat stroke. Rising seas will also cause added exposure to toxic and infectious agents due to disruption of waste disposal. Global warming is also expected to change human exposure to infectious disease agents — both vector-borne and microbes. The impact of climate change on diseases such as malaria, dengue fever, Murray Valley encephalitis, Ross River and Barmah Forest Virus is already becoming evident (Horton & McMichael 2008; OECD 2008b; WHO 2005b).
There have been a number of attempts internationally to raise awareness about, and support action for, the protection of the environment and thus human health. In 1972 the Declaration of the United Nations Conference on the Human Environment acknowledged that ‘…both aspects of man’s environment, the natural and the man-made, are essential to his well-being and to the enjoyment of basic human rights the right to life itself’ (UNEP 1972). In 1992 The United Nations Conference on Environment and Development (UNCED) in Rio de Janeiro reaffirmed the 1972 declaration and sought to build upon it. The Rio Declaration is a consensus document outlining the principles of sustainable development (UNCED 1992c). The document is commonly referred to as Agenda 21. The first principal of the Rio Declaration states: ‘Human beings are at the centre of concerns for sustainable development. They are entitled to a healthy and productive life in harmony with nature’ (UNCED 1992b). Five agreements on global environmental issues were signed in 1992 by many (but not all) countries. Two of these, The Framework Convention on Climate Change and The Convention on Biological Diversity, were formal treaties. The other three were non-binding statements on the relationship between sustainable environmental practices and the pursuit of social and socioeconomic development. The intent of Agenda 21 was to improve social and environmental conditions. The Statement on Forest Principles pledged parties to more sustainable use of forest resources. There have been some successes and many failures in attempting to achieve the noble ideals of these international agreements. Some are discussed below.
Reducing the release of chlorofluorocarbons (CFCs) and related compounds is an international success story. These compounds have been found to reduce the ozone layer of the upper atmosphere, which shields the surface of the earth from ultraviolet radiation from the sun. If the ozone layer continues to thin, then the intensity of ultraviolet radiation (UV) will continue to rise. The increased intensity of UV has impacts starting from the destruction of phytoplankton which is the base of the oceanic food chain right through to an increase in skin cancer and cataracts, and depressing the immune system in humans. The Montreal Protocol (UNEP 2000) shows what can be done with enough political will. The Montreal Protocol on Substances that Deplete the Ozone Layer is an international treaty designed to protect the ozone layer by phasing out a number of destructive substances such as CFCs. It is hoped that the ozone layer will be back to normal by 2015 but this depends on bringing the current black market in halons and CFCs in developing regions under control (Boyden 2005).
The Stockholm Convention on Persistent Organic Pollutants (POPs) came into force in 2004 with the aim of ridding the world of POPs (UNEP 2005). POPs are compounds which have been used in numerous technological processes. POPs enter the food chain and accumulate in the tissues of living organisms. POPs such as dioxins are released during paper pulp processing, coal combustion and waste incineration and polychlorinated biphenyls are used for a range of electrical, insulation, lubrication and other industrial purposes, and pesticides are used in agriculture (Boyden 2005). The Stockholm treaty is a good example of global recognition of the impact of human activity on the environment and the consequences for human health. The short- and long-term affects of POPs continue to be of concern for health professionals. Animals living in polluted waters have been seen to be more affected by several kinds of cancer, twisted spines and other skeletal disorders, ulcers, pneumonia, bacterial and viral infections, thyroid abnormalities and reproductive disorders than those in unpolluted waters (UNEP 2005). These disorders have not been proven conclusively to contribute to poor health in humans, but the precautionary principle is an important mechanism to prevent further damage to other species and perhaps humans. Vulnerable populations will be affected first and foremost.
The burden of disease is not shared equally and environmental degradation will most affect those who are socially vulnerable. The iceberg analogy presented in Chapter 1 (Figure 1.4) can be used again here. At the very bottom of the iceberg are the ecological and social determinants that underpin the health of entire populations and future populations. Children, frail aged and those who are poor, pregnant or have pre-existing diseases are affected most by environmental degradation (OECD 2008b). For example, the metabolic activity in children is higher than in adults and their bodies react differently when exposed to pollutants. Older people do not cope as well with temperature change. It is suggested that rural, regional and remote communities will be exposed to greater climate extremes and there may be even less access to fresh water and food supplies than there is now (Horton & McMichael 2008). Planning from now on will need to consider large numbers of environmental refugees. Underpinning health promotion practice with the principles of Primary Health Care will be crucial.
To aim for social justice and environmental justice is to aim for the same thing. One can’t be considered without the other. The principles support action to improve the lives of vulnerable people by reducing the risk conditions that contribute to a poor quality of life such as poverty and environmental degradation. Poverty contributes to environmental degradation and environmental degradation contributes to poverty.
Jared Diamond (2005) provides examples of numerous societies that have collapsed. His thesis describes the ‘ecological suicide’ of these societies where in the worst cases everybody in the society either emigrated or died (Diamond 2005: 6). The evidence presented in his thesis has been supported by a variety of scientists looking at collapsed societies from different perspectives. Diamond proposes that:
… the processes through which past societies have undermined themselves by damaging their environments fall into eight categories, whose relative importance differs from case to case: deforestation and habitat destruction, soil problems (salinization, erosion and soil fertility losses) water management problems, overhunting, over fishing, effects of introduced species, human population growth, and increased per capita impact of people.