Environmental exposures in the era of climate change.

The Pacifi c Basin includes countries in Asia, Australia, and North and South America. The Pacifi c Basin Consortium for Environment and Health (PBC), fi rst established in 1986, is an international organization that brings together scientists, policy makers, and representatives from non-governmental organizations with interest in health-related issues specifi c to this wide region. Initially, the PBC focused on hazardous waste, particularly methods and policies related to remediation. Because hazardous wastes pose immediate threats to human health, the mission of the PBC has expanded to cover the full range of issues related to hazardous wastes: toxic substances; human health and methodologies to minimize the generation and release of toxic substances; clean up of existing sources of hazardous wastes; and reduction of human exposure. Information about the PBC can be found at http:// www.pacifi cbasin.org . That hazardous contaminants do not respect national boundaries is increasingly clear. Air pollutants travel from one continent to another. Foods produced in one country may be sold anywhere on the globe and may carry such contaminants as pesticides and metals. Too often toxic materials are produced in one county (usually the more affl uent) for use or disposal in another. Although the Basel Convention of the United Nations was designed to prevent transport of hazardous wastes from one country to another, not every country (notably the United States) has ratifi ed this Convention. Notable examples include asbestos (1) , and worldwide traffi c in electronic wastes (E-wastes) from computers, cell phones, and other electronic equipment (2) . High-income, developed countries export these waste products to less-developed countries, where unskilled workers, frequently women and children, extract metals and other components from E-wastes in ways that pose serious threats to their health. Few issues related to hazardous substances and wastes are unique to any one country. Every country has problems with air pollution from industry and traffi c. Although the specifi c contaminants in drinking water may vary among countries, each must fi nd appropriate ways to provide safe drinking water and treat wastewater. Every country must dispose of solid wastes in ways that protect the environment and human health. Chemicals and metals that pose hazards to human health are present in emissions from industry, consumer products, and waste sites. Often these toxic substances contaminate food, drinking water, and air, posing hazards to human health from eating the food, drinking the water, and breathing the air. The issues related to environment and healthcare are likely to become more serious in the era of global warming and climate change. Climate change is a reality that already adversely affects health and the environment. As the ice sheets in Greenland and Antarctica melt, rising ocean levels threaten populations living near the coasts of many countries. This phenomenon will result in indirect impacts on health through ecological changes associated with altered land use and rising sea levels and through social changes resulting from economic effects (3) . The increased frequency of violent weather, fl oods, and droughts is likely to cause serious harm to human populations. Access to adequate quantities of safe drinking water is almost certainly going to be a much greater problem in the future, as desertifi cation engulfs previously arable land in geographic areas whose rainfall is already limited. Increases in global temperatures will not only disrupt patterns of rainfall and crops but also facilitate the spread of vectors of human disease, such as specifi c species of mosquitoes. Other direct impacts on health are likely to include changes in disease patterns, threats to food security, and changes in population growth and migration patterns (3) . Increases in global temperatures will increase the air transport of toxic chemicals. Without question, the issue of climate change and global warming is one of the most serious environmental threats mankind has known, and the failure of nations to deal with greenhouse gas emissions poses a serious threat to life as we know it. The health of the world ’ s population, and indeed its very survival, depend on cooperation and collaboration among nations to reduce chemical exposures and adapt to the changing environment brought on by climate change. There is a growing recognition that we live in a changing, connected world. Globalization has an impact on health in ways not seen before. The recent rapid spread of the H1N1 “ swine fl u ” , which became a global pandemic in the space of months, is a recent example. Globalization can also produce a rapid destabilization of economies, both globally and locally, as seen during the recent so-called “ global fi nancial crisis ” , with subsequent consequences for health and health-services delivery. Universal access to clean water, sanitation, and other foundational environmental goals are probably second in priority to economic and security objectives. National wealth is sometimes described as a precursor to environmental, sanitary, and health improvements (4) . In fact, a strong correlation has been found between wealth and sanitation/environmental health indicators, and signifi cant progress has been made in the last two decades to reduce poverty, to provide better health, and to offer access to improved water supplies and sanitation in the developing world (5) . There are also many examples of national progress in environmental protection