The rates of hospitalization and morality due to asthma are higher in urban, low-income, or minority communities (Weiss and Wagener, 1990; Weitzman et al., 1990). For example, in New York City, African American, Hispanic, and low-income populations were found to have hospitalization and mortality rates from asthma three to five times higher than those for the general New York City population (Carr et al., 1992). African American children are three times more likely than white children to be hospitalized for asthma and asthma-related conditions and four to six times more likely to die from asthma (Mannino et al., 1998; Stapleton, 1998).
These data might be viewed as demonstrating that urban asthma is an environmental justice problem. The situation is quite complicated, however, and a conclusive finding of an environmental justice problem is not free of doubt. First, the clinical diagnosis of asthma is not entirely clear-cut, and diagnostic methods and accuracy may vary among different population groups (Gergen, 1996). Second, the etiology of asthma is complex and multidimensional. A variety of toxic, allergenic, dietary, and infectious agents, as well as genetic and acquired susceptibility factors, contribute to the disease. Environmental agents that may induce new-onset asthma or that may aggravate preexisting asthma may come from outdoor or indoor sources at home, work, school, or other locations. Studies have shown that important sources of allergens for asthmatics are household dust mites and cockroaches, which are more likely to be present in urban settings and which are more likely to be encountered by children who spend a great deal of time indoors (Vogel, 1997). Consequently, the attribution of causality to a specific environmental hazard and apportionment of causality among various potential causes are exceedingly difficult if not impossible at this time.
Not all segments of the U.S. population have benefited to the same extent from advances in health status and gains in life expectancy. Racial and ethnic minority groups, individuals of low socioeconomic status, and medically underserved populations, among others, face lower life expectancies and greater health problems than the U.S. white population (Council of Economic Advisors, 1998; National Center for Health Statistics, 1998b). In addition, many communities contain potential sources of environmental health risks (e.g., industrial facilities, waste treatment sites, or waste disposal sites). These can affect all racial, ethnic, and socioeconomic groups, but there is substantial evidence that minorities and lower-income groups face higher levels of exposure to these hazards in terms of both frequency and magnitude. Although direct links between exposures and health are weak in many instances, the committee believes that allegations of environmental justice problems are frequently well founded and must be taken seriously enough to warrant careful assessment.