Urbanicity, urbanization, and the urban environment

We live in an increasingly interconnected world, as some like to say, a "global village." As in any village, social, economic and biophysical environments shape individual action and interaction, which, in turn, influence the quality of life and the health of inhabitants. Technology, information, media, food, goods and services, as well as environmental pollution and diseases are shared among villages, cities, countries and continents. Not only are these exchanges great in scope, but the magnitude and speed of interaction among individuals and populations is also increasing. For example, international trade grew 8.6% per year during the decade 1990-1999 (World Trade Organization, 2000a, b), with an estimated US$1.7 trillion in daily global trading (Lee, 2000). An estimated 760 million people traveled to international destinations in 2004 (World Trade Organization, 2005), and circumnavigation of the globe is now possible in a mere 36 hours (Smolinski, Hamburg, & Lederberg, 2003). Immigration contributes to global exchanges, with an estimated 175 million individuals spending at least one year in another country (United Nations, 2002). Additionally, approximately 17 million refugees and internally displaced persons migrate from their homes every year (United Nations High Commissioner for Refugees, 2004). These trends of growing interactions on the global scale shape the environments in which we live and which influence our well-being and our health.