Airborne Dioxins, Furans, and Polycyclic Aromatic Hydrocarbons Exposure to Military Personnel in Iraq

Abstract

Objectives: The objective of this study was to use ambient polycyclic aromatic hydrocarbon (PAH), polychlorinated dibenzo-p-dioxins (PCDD), and polychlorinated dibenzofurans (PCDF) concentrations measured at Joint Base Balad in Iraq in 2007 to identify the sources of these species and their spatial patterns.

Methods: The ratios of the measured species were compared with literature data for likely emission sources. Using the multiple site measurements on specific days, contour maps have been drawn using inverse distance weighting (IDW).

Results: These analyses suggest multiple sources, including the burn pit (primarily a source of PCDD/PCDFs), the transportation field (primarily as source of PAHs), and other sources of PAHs that include aircraft, space heating, and diesel power generation.

Conclusions: The nature and locations of the sources were identified. PCDD/PCDFs were emitted by the burn pit. Multiple PAH sources exist across the base.

Figure 1

Map of the study area and wind roses computed seasonally on 2007 data. JBB sites: burn-pit (BP); guard tower (GT); transportation field (TF); H6-Housing (H6); contingency aeromedical staging facility (CASF, CA).

Figure 2

Distributions of analytical results as box-plots (top) and average relative fractions of homologues and congeners (bottom). Box-plots: boxes represent inter-quartile ranges, black lines are medians, whiskers are quartiles ± (1.5*inter-quartile ranges), red crosses are arithmetical means. NAP is partially hidden on the PAH fraction plot because it represents about 70-78% of total mass concentration of PAHs. 2,3,7,8-TCDD-TEQ are computed according to TEQs proposed by Van den Berg et al.; BaP-TEQ are computed on TEFs according to Nisbet and LaGoy and Larsen and Larsen.

Figure 3

Scatterplots between pairs of diagnostic ratios for PAHs (top); the regression between PCDDs and PAHs (bottom left) and mixed ratios among PCDDs, PCDFs and PAHs (bottom center and right). Data collected at JBB are colored. Data from literature are also reported for a comparison: simulated US military waste; legacy heavy-duty diesel engines at transient on-road settings; common in-use heavy-duty diesel engines without after-treatment devices at cruise, urban and idle thrusts; modern diesel engines with and without exhaust gas after-treatment at average conditions;^, various turbofan engines.

Figure 4

Interpolated maps for the sum of the PCDD compounds (A), PCDF compounds (B), and PAH compounds (C) on January 3, 2007.