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FIGURE 7-1 Committee’s process for assessing the long-term consequences of exposure to burn pit emissions and the design of an epidemiologic study.

between the burn pits in these countries and in Iraq and Afghanistan, and in particular at JBB, is unknown. Available information suggests that burn pit practices varied among bases and over time; the amount of waste burned daily at JBB is estimated to have varied by an order of magnitude over its years of operation.

Combustion Products and Exposure Considerations

Air samples were collected upwind of the burn pit and downwind in an open area and in a housing and work area. The sampling targeted several chemical categories, including particulate matter (PM) and metals, volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs), and polychlorinated dibenzodioxins and furans (PCDDs/Fs). It is notable that some U.S. criteria air pollutants, such as sulfur dioxide, nitrogen dioxide, carbon monoxide, and ozone, were not analyzed for at JBB. CHPPM found measurable concentrations of many of the chemicals for which the samples were analyzed, albeit at concentrations below those typically observed in urban airsheds outside the United States. However, the samples contained contributions from other sources of air pollution in the area, so measured air contaminants could not be directly attributed to the JBB burn pit. Based on its analysis of the CHPPM data, the committee concluded that:

  • Background ambient air concentrations of PM at JBB are high, with average concentrations above the U.S. air pollution standards, and are most likely derived from local sources;
  • PCDDs/Fs were detected at low concentrations in nearly all samples (although high compared with even polluted urban areas), and the burn pit was likely the major source of these chemicals; and
  • Ambient VOC and PAH concentrations were similar to those reported for polluted urban environments outside the United States, and the major sources of these pollutants are regional background, ground transportation, stationary power generation, and the JBB airport.

The data thus indicate that military personnel were exposed to a mixture of combustion products from the burn pit and to other air pollutants from local and regional sources, including other combustion sources, industry, and wind-blown soil. It is likely that people who worked at or near burn pits were exposed to combustion emissions and



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