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Climate change is the biggest health threat of the 21st Century

Publication date: May 15, 2009 12:49:33 PM

A major report on managing the health effects of climate change, launched jointly by The Lancet and UCL (University College London) today, says that climate change is the biggest global health threat of the 21st Century. Furthermore, lead author Professor Anthony Costello says that failure to act will result in an intergenerational injustice, with our children and grandchildren scorning our generation for ignoring the climate change threat—with similar moral outrage to how we today look back on those who brought in and did nothing to stop slavery.

This first Lancet Commission is the work of UCL academics from many disciplines across the University – including health, anthropology, geography, engineering, economics, law, and philosophy. Prof Costello says that this climate change project brought down the traditional interdisciplinary barriers common at all universities, and hopes it could act as a model for global governance bodies to work together. The UCL team focused on six key areas for their report: patterns of disease and mortality, food security, water and sanitation, shelter and human settlements, extreme events, and population migration.

Professor Costello says: “The big message of this report is that climate change is a health issue affecting billions of people, not just an environmental issue about polar bears and deforestation.” He adds: “The impacts will be felt not just in the UK, but all around the world — and not just in some distant future but in our lifetimes and those of our children.” The Commission discusses the global health implications of the Intergovernmental Panel on Climate Change (IPCC) projections — from the optimistic average global temperature rise of 2oC to the catastrophic 6oC. The authors consider a wide range of pathways through which climate change could exert its effects on health, some of which may happen before others. Changing patterns of disease and mortality would emerge in a greater rate of transmission and geographic spread of traditionally tropical endemic diseases such as malaria and dengue fever. Heat — the ‘silent’ killer — has a major effect on mortality, with the 2003 heatwave causing up to 70,000 excess deaths in Europe. While some people believe populations in India and Africa may be more resistant to heat waves, there is little evidence of this and major heatwaves could increase death rates in these populations more than in high-income countries.

Food and water security will be a major issue as climate change progresses. Scientists believe that crops are much more sensitive to temperature changes than first thought—a 1oC change can make a difference of 17% in yields. Professor Costello says: “If we are going to get early changes in the next 20 or 30 years, falling crop yields could trigger more of an effect through rising food prices. Look at what happened last year when food prices rose globally. And one billion people currently have calorie deficient diets—this situation will get worse as demand increases from India, China, and other nations with a population boom.” Up to 250 million people in Africa will face water shortages by 2020 if no action is taken on adaptation. Water and sanitation are crucial to prevent gastroenteritis and malnutrition. Melting glaciers and changing river flows and rainfall patterns are already causing flooding and droughts.

Rapid urbanisation, particularly in developing nations, leads to inadequate housing, particularly slums, which are the most exposed during extreme climatic events. Extreme events, including cyclones and hurricanes, have doubled over the past 20 years, according to the insurance companies who insure against them. But in an event such as a cyclone, a rich nation would normally have relatively few casualties compared to poorer countries. Consider Hurricane Katrina with a loss of 1,850 lives compared with the recent cyclone in Burma which is thought to have claimed 150,000 lives. Of the 20 largest cities in the world, 13 are on a coast*. While sea levels have been predicted to rise, from anywhere between 0.5 m and 1.2 m over the 21st century, some predictions as high as 5 m are beginning to emerge. This would be catastrophic.

Prof Costello says: “We might be reaching a tipping point in public opinion. I think the health lobby has come late to this debate and should have been saying more. Young people realise this is the great issue of our age.” He proposes three action points leading from this report: “First, we have to add the health lobby to the mitigation debate – they must emphasise the threat to our children and grandchildren from greenhouse gas emissions and deforestation. Second there must be a focus on health systems — there is massive inequality in health systems throughout the world. Because of this, the loss of healthy life years as a result of global environmental change is predicted to be 500 times higher in Africa than in European nations, despite Africa making a minimal contribution to the causes of climate change. Third we must develop win-win situations whereby we mitigate and adapt to climate change and at the same time significantly improve human health and well being. There are major health benefits from low-carbon lifestyles, which can reduce obesity, heart and lung disease, diabetes and stress.”

He concludes: “We believe that all the main players —health, political, scientific, technological, and civil society must come together. We’ve laid out a framework for action, and we have called for a collation of information on the health effects of climate change leading up to a major international conference in the next two years. We especially want representation from poorer nations. This conference would set out some clear indicators, targets, and accountability mechanisms. We need a new 21st century public health movement to deal with climate change.”

For Professor Anthony Costello and other authors from UCL, please contact Ruth Metcalfe, UCL Media Relations Manager on T) +44 (0)20 7679 9739, M) +44 (0)7990 675 947, out of hours +44 (0)7917 271 364, E) r.metcalfe@ucl.ac.uk

Lancet Press Office T) +44 (0) 20 7424 4949 E) pressoffice@lancet.com

For the full Lancet UCL Commission, see: http://press.thelancet.com/climatechangefinal.pdf

For key messages and quotes documents, see attached word documents

Notes to editors:

*please note – quotes in this press release are direct from Prof Costello; for quotes direct from the report, please see separate key quotes document.

**World’s 20 largest cities: 1. Tokyo, Japan 2.Seoul, South Korea 3.Mexico City, Mexico 4. New York City, USA 5. Mumbai, India 6. Jakarta, Indonesia 7. Sao Paulo, Brazil 8. Delhi, India 9. Osaka—Kobe—Kyoto, Japan 10. Shanghai, China 11. Manila, Philippines 12. Hong Kong, China 13. Los Angeles, USA 14. Kolkata, India 15. Moscow, Russia 16. Cairo, Egypt 17. Buenos Aires, Argentina 18. London, UK 19. Beijing, China 20. Karachi, Pakistan.