Tony McMichael Colin Butler. National Centre for Epidemiology and Population Health The Australian National University Canberra

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1 Tony McMichael Colin Butler National Centre for Epidemiology and Population Health The Australian National University Canberra

2 Global health indicators have been improving - with some local and temporary exceptions World population size has been growing rapidly So have aggregate economic activity and consumption levels Simultaneously, many large-scale environmental and ecological indices have been declining Can we explain this apparent paradox? What is the relationship of population health to sustainable development? Anticipatory versus empirical approaches: Is evidence and information (the WHO orthodoxy) adequate for Big Policy?

3 Mortality Trends, Sweden, Males Females Probability, at birth, of dying by age 5 yrs Female 5q0 Male 5q Probability, at age 15, of dying by age 60 yrs Female 45q15 Male 45q15 Value 0.3 Value Developing Countries, 1990s Year Year Based on: Murray C, WHO, 2002

4 1,400 Age-standardised death rate by social class (I-V), adult males, England and Wales, ,200 Deaths per 100,000 1, I V IV III II Year Based on ONS UK: Health Inequalities Decennial Supplement

5 0.8 Adult mortality % by 10% q0 Infant/child mortality Based on: WHO, 2002

6 Index of Global Environmental Change (%) Year Extension of earlier analysis, of CD Butler

7 Time trend in global per-person production of cereal grain 350 kgs grain per capita

8 Three possible explanations: Modern societies, via technological, economic and political achievements, have become immune to environmental adversity. Adverse health effects are already occurring, but we cannot yet see them. Lag period between environmental decline and health impacts. Lag reflects: (i) living off capital, (ii) buffering by culture. Explanation 1 is untenable. Historically, the experience of many societies shows that, eventually, all are accountable within an ecological sustainability calculus. A combination of explanations 2 and 3 seems most plausible.

9 Human Population Carrying Capacity

10 Non-human species: CC = f [natural capital] Humans: CC = f [NC, FC, BC, SC, HC] Inter-convertibility of types of capital Ability to expand HCC via culture/technology But: need to conserve the essential NC

11 The environment sets limits on the size of the supportable local human population (given its particular level of demands ). Societies find ways to extend that limit. Sustainable societies achieve a trade-off between supportable population size and sustainable environmental impact.

12 Financial capital: international coffee price Social capital: resurgent tribal tensions Natural capital: shortage of arable land Å

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14 Hunter-gatherer Agrarian Human Carrying Capacity Population Demand on Environment Globally developed Industrialising

15 Tension between the Health Transition Will economic globalisation, and wealth creation, facilitate the Health Transition and help us achieve Sustainable Development? Assumption: That the global human carrying capacity is sufficiently elastic - to technology and greater wealth - to support, in future, a bigger and richer (higher consuming) population. Probably erroneous! and Sustainable Development Current modes of wealth creation are also eroding Earth s lifesupports, thus jeopardising the sustainability of current and future health gains.

16 Population size, and distribution Technologies Environmental impact Economic activity Wastes Consumption patterns Carrying capacity: critical thresholds Health losses Knowledge Population health status? Culture Social capital Health gains Recent Past Present Future

17 A change in human health/survival is responsive, not predictive Further, this biological response is delayed by the interposing of culture and technology which expands HCC, usually at the expense of natural capital. Deferral of ecological debt e.g.: Succession of ocean fisheries Irrigation of drylands Cyclone-proof housing

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19 Trends in selected causes of death for women aged years in Russia SDR per Accidents and violence Ischaemic heart disease Stomach cancer 20 Rheumatic heart disease Year Breast cancer Shkolnikov & Leon

20 75 Life 65 expectancy (yrs) Botswana Uganda South Africa Year

21 HCC has a prospective ( carrying ) dimension Can today s population, with its current life expectancy, and demands, be carried? Global Years of Life Expectancy (GYLE) = Global Population x Life Expectancy at birth i.e., current demand + committed demand on NC If so, can this demand be met without detriment to future generations?

22 Population and GYLE (billions) (log scale) Global population and global years of life expectancy (GYLE), GYLE (billions) Population (billions) Year

23 Global population, global years of life expectancy (GYLE), and Index of Global Env Change (IGEC): Population and GYLE (billions) (log scale) IGEC (%) GYLE (billions) Population (billions) Year

24 Reduced rate of increase in life expectancy But, alternative explanations Increased infant mortality (classical indicator) Resurgence of infectious diseases Reduced fertility (state- or family-initiated) Increased tension and conflict, relating to environmental assets (space, resources, food)

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26 Global income distribution (US$), Gini coefficient (%) Butler CD, 2001

27 Environmental brinkmanship between countries (Resource extraction, trade patterns, wastes) Over-use of local natural resources Affluent consumption Environmental damage Inequality Great wealth Medium wealth Gains in life expectancy Gains in life expectancy Arrested (?reversed) health gains Poverty Poor health Health losses NOW FUTURE

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29 20 Average Global Temperature 19 ( O C) This presents IPCC (2001) a rate-ofchange a problem o C increase for many estimates natural systems/processes Central estimate = 3.0 o C High Low Band of historical climatic variability Year

30 Estimates Preliminary of Additional, Estimates Global, of Risk Numbers Functions of for People 4 Major at Risk Health- of 4 Major Related Health-related Consequences Impacts of Climate of Climate Change Change (DETR, by circa UK, ) Additional millions of people at risk of hunger, malaria and flood Additional 450 millions 400 of people at risk 350 of hunger, malaria 300 and flood ppmv 750ppmv Hunger Water shortage Malaria Flooding 1 o C 2 o C 3 o C Temperature Increase Temperature increase Unmitigated Additional millions of people at risk of increased water shortage Legend Risk of flooding Additional millions Risk of hunger of people at risk of increased Risk of malaria water shortage Risk of water shortage Based on a set of studies commissioned by UK Govt.

31 Gains in health and longevity over the past century have followed urbanisation, social modernisation, industrialisation and increasing material wealth, plus advances in public health and health care. However, those health gains have depended, to an uncertain extent, on the depletion and degradation of the world s natural environment. Theory, personal experience, and an increasing body of empirical data* suggest the existence of critical thresholds beyond which lie dangers to society and risks to population health. * Scheffer et al., 2001; Rauch, 2002

32 Recent mortality/health trends, globally and regionally, actually cannot tell us if our socioeconomic development path is sustainable. Health outcomes are responsive, not predictive. Further difficulties are: Cause-effect lag times Multiplicity of influences on population health Uncertain determinants of the environment s human carrying capacity We must therefore use an anticipatory approach.

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