among other things, to endocrine and reproductive system disruptions in animals and humans. Many of these persistent organic pollutants, or POPs, which are present in tens of thousands of synthetic chemicals, have been known to have delayed impacts, sometimes visible only after many years. They accumulate in fatty tissue and are passed up the food chain. The U.S. National Academy of Sciences reports that insufficient information exists for even a partial health assessment of 90 percent of chemicals in the environment (Jackson, 1996, p. 30). The US Toxic Release Inventory makes public just 7 percent of high-production chemicals, those used at 1 million pounds or more each year. And what little testing and evaluation is done on these chemicals, virtually nothing is known about the synergistic effects of these chemicals when they mix together in the real world (Colburn, Dumanoski, & Myers, 1996). Synthetic chemicals are the major source of epidemic levels of building-related illness, which the US EPA and World Health Organization both consider serious health problems. (These petrochemical-related problems in indoor environmental quality in buildings will be dealt with more specifically in Chapter III). The refineries and chemical plants involved with these chemicals are among the industrial worlds largest sources of hazardous waste and toxic emissions. Over 90 percent of US Superfund cleanup sites are petrochemical-related. According to Gardner and Sampat, there are some 40,000 Superfund sites, and the Environmental Protection Agency estimates that cleanup of just the 1,400 worst sites will cost $31 billion. The world situation is even worse. In a 1991 waste survey of more than 100 nations by the International Maritime Organization, almost two thirds said that hazardous