Climate change environmental image

Large-scale and global environmental hazards to human health include climate change, stratospheric ozone depletion, changes in ecosystems due to loss of biodiversity, changes in hydrological systems and the supplies of freshwater, land degradation, urbanization, and stresses on food-producing systems.

Appreciation of this scale and type of influence on human health requires a new perspective which focuses on ecosystems and on the recognition that the foundations of long-term good health in populations rely in great part on the continued stability and functioning of the biosphere's life-supporting systems. It also brings an appreciation of the complexity of the systems upon which we depend.

Harmful effects of environmental change and ecosystem impairment on human health.

Protecting health from global environmental change requires management at many levels, from the social and economic drivers of environmental change, to the resulting hazards and exposures for human populations. WHO supports this linkage of environmental and health agendas, for example by providing health expertise into the UN Conventions on Climate Change, Biological Diversity and Desertification, and by advising the health sector on the necessary responses to address the health risks posed by large-scale environmental change.

Air quality guidelines for health

Clean air is considered to be a basic requirement of human health and well-being. However, air pollution continues to pose a significant threat to health worldwide. According to a WHO assess¬ment of the burden of disease due to air pollution, more than 2 million premature deaths each year can be attributed to the effects of urban outdoor air pollution and indoor air pollution (caused by the burning of solid fuels). More than half of this disease burden is borne by the populations of developing countries.

Air quality guidelines have been published by WHO in 1987 and they were revised in 1997. Given the wealth of new studies on the health effects of air pollution that have been published in the scientific literature since the completion of the second edi¬tion of the Air quality Guidelines for Europe, includ¬ing important new research from low-and middle-income countries where air pollution levels are at their highest, WHO has undertaken to review the accumulated scientific evidence and to consider its implications for its air quality guidelines. The result of this work is presented in this document in the form of revised guideline values for selected air pollutants, which are applicable across all WHO regions.

Health and environment: images from around the world

This gallery of 40 winning entries from the 2007 international photo and video contest showcases the intricate link between the environment and public health. This year the focus of the annual contest was on health and environment, as part of WHO's efforts to raise awareness about the importance of healthier environments.

The annual contest began in 2002 with the overall theme of "images of health and disability". It aims to promote the understanding of health and disability as described in the International Classification of Functioning, Disability and Health (ICF).

The 2007 entries include positive images that highlight the beneficial effects of safe and healthy environments: children playing in healthy, supportive and enabling environments; safe water; clean air, and a stable climate etc.

In contrast, other images paint the grim reality of our environment today: showing the hazards of shipbreaking; children drinking arsenic-laden water; people breathing in thickly polluted air; health risks for workers at garbage dumps etc.

The video entries include a lively rap song on indoor air pollution and safety in the house, and show the impact of waste, poverty and the stigma of mental and physical disability.

Photographers and video producers from 56 countries submitted more than 2 500 entries. Here are the winning entries from each of the four categories.