keynote speaker Timothy Wirth, president of the United Nations Foundation. Money has not been invested in the research needed to build on the accomplishments of the 1970s, said Lynn Goldman of Johns Hopkins University. Despite a near doubling in the size of the National Institutes of Health budget, there has not been a comparable increase in the investment in public and environmental health—particularly in the area of prevention, she noted. Several speakers highlighted a number of challenges we face in the future, including population growth, urban sprawl, and energy use.

Many speakers emphasized that the natural environment and human health have strong connections. Research has demonstrated this connection, and our own behavior reflects this link: people flock to our national parks and zoos, and pet ownership remains high year after year. Many Americans search for solitude or a place to commune with nature. As urban sprawl continues, communities increasingly are relying on federally owned land as a place to provide much needed green space, according to David Hayes, U.S. Department of the Interior. He noted that this is providing an increasing strain on the environment, and other speakers, such as Mayor J. Christian Bollwage of Elizabeth, New Jersey, emphasized the need to protect our green space.

Advances in the field of environmental health have taught us much about human health hazards. For example, air pollution can cause respiratory disease, heavy metals can cause neurotoxicity, and global climate change is likely to fuel the spread of infectious disease, said Howard Frumkin, Rollins School of Public Health. Thomas Lovejoy of the World Bank spoke about how biodiversity is a necessity for human health. For example, many microbes are essential for cleaning up environmental health hazards, while other organisms provide vital products (e.g., cyclosporin) for use in the treatment of human disease. The challenges of pollution control, sustainability, and maintaining biodiversity will require a more holistic and integrated approach to assessing and redressing the impact of the environment on human health.

The built environment—that is, the environment designed and constructed by humans—presents as many opportunities as challenges to environmental health, according to many speakers. Cities and designers have created places in which we work and live as if the individuals will leave and move to a new place, noted William McDonough, University of Virginia. Several speakers asserted that modern society needs to develop a new strategy, assigning a true value to building materials and embracing the notion that everything can be recycled. For example, interior environments should be designed with human needs and health in mind; people should be provided with natural daylight and fresh air that can be delivered under their control.

Providing a healthy environment must extend to all people regardless of race, socioeconomic status, or location, said several speakers. Thirty years after studies documented the toxicity of lead, childhood lead poisoning still occurs, noted Mindy Fullilove of Columbia University. She added that false dichotomies often are constructed when trying to resolve environmental issues in the built environment, such as jobs versus the environment or jobs versus health.