was detected among the samples taken (see Chapter 4, Table 4-6). The pollutants listed in Table 5-1 were detected in at least 5% of the air monitoring samples collected at JBB in 2007 and 2009 (n = 47 chemicals). There are an additional four pollutants (1,2,4-trichlorobenzene, 1,3-dichlorobenzene, 1,3-butadiene, and 1,2-dichlorobenzene) that were detected at JBB although in fewer than 5% of the samples, but they were included in the committee’s assessment because they are expected to be present in burn pit emissions on the basis of burn barrel experiments (Lemieux et al. 2003, 2004; see also Chapter 4, Table 4-6). Health effects of particulate matter, dioxins (as represented by 2,3,7,8-tetrachlorodibenzo-p-dioxin [TCDD]), and metals detected at JBB (lead, zinc, and antimony) are also described. In all, 56 pollutants are profiled in Table 5-1.
When available, specific cancer and noncancer health effects data for the pollutants in Table 5-1 were obtained from the U.S. Environmental Protection Agency’s (EPA’s) Integrated Risk Information System (IRIS), Agency for Toxic Substances and Disease Registry (ATSDR) Toxicological Profiles, the National Institute of Occupational Safety and Health (NIOSH), or the National Library of Medicine’s (NLM’s) Hazardous Substance Data Bank. IRIS is the source of much of the toxicity information discussed in this chapter. The toxicity values and supporting documentation developed by the EPA and other agencies are the result of extensive review and synthesis of health effects literature and are designed for practical application in assessments of human health risks. The committee recognizes there are concerns regarding IRIS (NRC 2009); nevertheless, IRIS and other agency databases provide the best readily available evaluation of health effects from exposure to toxic substances.
HEALTH EFFECTS OF SELECTED AIR POLLUTANTS DETECTED AT JBB
The evaluation of air monitoring data from JBB reported in Chapter 4 indicates that combustion products from burn pits were associated with low concentrations of dioxins and dioxin-like compounds but contributed a relatively small proportion of PM compared to local dust and other sources. The committee recognized that personnel at military bases similar to JBB were exposed to many hazardous agents associated with adverse health effects in addition to burn pits. These exposures may result from use of kerosene heaters, JP-8 fuel, and tobacco products in addition to the hazards and stress inflicted by war. Assessment of these additional exposures was outside the committee’s scope and thus focus was on only exposures related to burn pits. While not measured directly, first hand descriptions of the burn pits describe volumes of smoke resulting from the burn pit and use of JP-8 fuel to encourage combustion (see Chapter 2). Both smoke and JP-8 fuel are associated with adverse health effects as described below.
JP-8 and similar fuels were used by the military to power aircraft, ground vehicles, tent heaters, and cooking stoves. These fuels were also used for less conventional purposes, such as suppressing sand, cleaning equipment, and burning trash. Military personnel serving in the Gulf War theater of operations could have been exposed to the uncombusted fuels, the combustion products from the burning of those fuels, or a combination of uncombusted and combusted materials (IOM 2005). Health effects of JP-8 are similar to those of kerosene, the primary component of JP-8, exposures generally causing nervous system effects. Large doses of inhaled JP-8 are known to cause headaches and fatigue, and affect concentration and coordination, while more chronic exposures can affect sleep, motivation, and cause dizziness, but not cancer (ATSDR 1998). As part of the IOM’s continuing series of Gulf War and Health reports, a previous IOM committee assessed the toxicological and epidemiological effects of these fuels and their combustion products. That committee did not find any association between exposure to uncombusted fuels and long-term health effects. Conversely, fuel combustion products were found to have sufficient evidence of an association with lung cancer; limited suggestive evidence of an association with several other cancers (nasal cavity, nasopharynx, oral cavity, laryngeal, and bladder cancers), reproductive effects, and incident asthma (IOM 2005). (See Chapter 6 for a description of the categories of association used for these combustion products and health effects.)
While products of combustion vary greatly based on fuel composition and conditions of the burn, several health effects have been described consistently in association with exposure to smoke. Studies have examined health effects from exposure to ambient air pollution, exposure to wood smoke from indoor wood-burning stoves and fireplaces, and exposure to smoke from wildland or agricultural fires. Wood smoke has been associated with premature death, chronic obstructive pulmonary disease (COPD), tuberculosis, acute lower respiratory infections,