2.5 air pollution mainly comes from the production of goods consumed by white people while this pollution is disproportionally inhaled by communities of color. Therefore, these communities bear a disproportionate burden of environmental pollution known as pollution inequity and are more likely to face health risks such as cancer or asthma. Studies show that patterns in race and income disparities not only indicate a higher exposure to pollution but also higher risk of adverse health outcomes. Communities characterized by low socioeconomic status and racial minorities can be more vulnerable to cumulative adverse health impacts resulting from elevated exposure to pollutants than more privileged communities. Blacks and Latinos generally face more pollution than whites and Asians, and low-income communities bear a higher burden of risk than affluent ones. Racial discrepancies are particularly distinct in suburban areas of the South and metropolitan areas of the West. Residents in public housing, who are generally low-income with poor access to health care and cannot move to healthier neighborhoods, are highly affected by nearby refineries and chemical plants. Community groups and academic researchers have argued the unequal distribution of pollution on the poor and communities of color is an “environmental justice”. Policy makers and researchers concerned with improving environmental justice for communities situated next to major sources of air pollution have developed a number of regulatory tools to identify air pollution hotspots. The EPA, for example, utilizes their Risk-Screening Environmental Indictors (RSEI) model to identify hotspots from a score of 3 to 15, with higher scores indicating closer proximity to hazards. Individual states have also taken steps to improve identification and surveillance. California's AB 2588 Air Toxics “Hot Spots” Program, enacted in 1987, seeks to collect emission data, determine health risks, and notify local residents of major risks. By identifying hotspots regulators hope these tools will help them reduce pollution and inform nearby populations through the health risk assessments of individual pollutants and facilities that are summed in each zone to develop a total lifetime cancer risk. Air pollution hot spots are also at issue in pollution-trading programs, such as cap-and-trade systems designed to control pollution. These programs can potentially exacerbate effects from air pollution hotspots if the differences in chemical hazards are ignored. These programs also cause pollution to be mitigated towards where credit-buying firms are located. Factories can purchase emissions reduction credits from other firms, which leads to concentrated areas of pollution since