Six scientists including Richard Hortoc, the editor of the journal, has published a manifesto in 8th of March 2014. Manifesto stated that it was no longer possible to protect human health without protecting the planetary health, and was a call for action for health and public health workers, politicians, international organizations, academicians, and for everyone who cares for the welfare of next generation. Manifesto stated that unlimited growth is not possible and inequalities are increasing and that we need immediate transformations in our values against the risks we faced and in our applications. About a year after that, the Planet Health Commission, published an article entitled "Safeguarding Human Health in the Anthropocene epoch"(2). The word "anthropocene" in the beginning of the article which was first cited by Nobel Prize laureate chemist Paul Crutzen was a reference to the statement that the Holocene age was ending and that we have entered a new era due to the effects of the people on the planet (3). In this new era humanity was improved to a level never experienced before. For example, the life expectancy which was 47 years in 1950-1955 has increased to 69 years in 2005-2010, while the rate of child mortality under the age of five has declined from 214 to 59 per thousand births, while the population has increased, poverty has decreased in world scale2. These achievements are a result of major advances in public health, health care, education, human rights, agriculture, infrastructure and technology. Our planet has supported this development with ecological and biophysical systems; enabling humans to access resources with vital resources such as clean air, food, potable water and energy. However, these sources are not limitless, and as a result of human activities, environmental changes take place all over the planet and the planet is gradually losing its power to support human health. It has been reported that at least 60% of the services provided by ecosystems, such as the regulation of the quality of the air, the purification of water, have deteriorated or have lost their sustainability.
Climate change is the most important of the environmental changes due to human activities4. Greenhouse gases arising from the use of fossil fuels in transport, at home, in agriculture and in industry, cause global warming by the heat trapping. Studies show that the main greenhouse gases (carbon dioxide, methane and nitrous oxide) have reached their highest levels in the last 800,000 years. The average global surface temperature has increased by 0.8 oC since 1880. It is predicted that the temperature increase will be between 2.6-4.8 oC at the end of 21st century.Consequently, it is anticipated that extreme heat, extreme precipitation, drought in some areas will emerge, causing significant changes in both plant and animal populations in terms of both number and distribution. One of the effects of the increase in temperature is the melting of the glaciers and associated in sea level rise. Accordingly, it is thought that the coastal strips will become inaccessible and the agricultural areas in these areas will be lost.
Environmental changes disrupt ecosystems, affecting the services provided by them. These services include supply services such as food, water, fuel, medicine and novel chemical compounds provided by ecosystems to humans; regulatory services such as regulation of climate, water, pollution, air quality, diseases and erosion; supporting of the habitat by cultural services having aesthetic, recreational and spiritual dimensions, and support services such as sustainment of biodiversity and soil formation.
One of the basic elements that make up the concept of planetary health is the "ecological public health" model. The main argument of this model, which was put forward by Tim Lang and Geof Rayner, is that health depends on the successful combination of the natural world and social life 9. An important conceptual change introduced by this model is that the health sector needs to take responsibility not only for the health sector but also for the protection and development of health. Planetary health in this context is the health of human society as well as the natural systems where human civilization flourish 1,2. It is clear that human health cannot be protected without ensuring sustainability of natural systems. Therefore, there is a need for change in concepts (for example: measuring development not only with measures such as Gross Domestic Product but also with environmental indicators), information (such as prioritizing social and environmental determinants of medicine and transferring resources to transdisciplinary research) and practice (how institutions and states perceive and respond to threats, sustainable development, use of technology, etc.) 2. The Faculty of Medicine of İzmir University of Economics aims to raise awareness of planetary health and its effects on human health among students and society through education and research, and regards this as a part of academic responsibility. Global environmental changes (I) can be direct (eg heat), (ii) secondary (due to the change of natural systems) or (iii) indirect (social turmoil).