Occupational PAH exposures during prescribed pile burns.

Wildland firefighters are exposed to particulate matter and gases containing polycyclic aromatic hydrocarbons (PAHs), many of which are known carcinogens. Our objective was to evaluate the extent of firefighter exposure to particulate and PAHs during prescribed pile burns of mainly ponderosa pine slash and determine whether these exposures were correlated with changes in urinary 1-hydroxypyrene (1-HP), a PAH metabolite. Personal and area sampling for particulate and PAH exposures were conducted on the White Mountain Apache Tribe reservation, working with 21 Bureau of Indian Affairs/Fort Apache Agency wildland firefighters during the fall of 2006. Urine samples were collected pre- and post-exposure and pulmonary function was measured. Personal PAH exposures were detectable for only 3 of 16 PAHs analyzed: naphthalene, phenanthrene, and fluorene, all of which were identified only in vapor-phase samples. Condensed-phase PAHs were detected in PM2.5 area samples (20 of 21 PAHs analyzed were detected, all but naphthalene) at concentrations below 1 microg m(-3). The total PAH/PM2.5 mass fractions were roughly a factor of two higher during smoldering (1.06 +/- 0.15) than ignition (0.55 +/- 0.04 microg mg(-1)). There were no significant changes in urinary 1-HP or pulmonary function following exposure to pile burning. In summary, PAH exposures were low in pile burns, and urinary testing for a PAH metabolite failed to show a significant difference between baseline and post-exposure measurements.

Analytical method using gas chromatography and ion trap tandem mass spectrometry for the determination of S-triazines and their metabolites in the atmosphere.

Gas chromatography-ion trap detector (GC-ITD) was used to detect atmospheric triazines and their degradation products in the gaseous and particulate phases. Because triazines and their metabolites are expected to be present at very low concentrations and enclosed in the complex atmospheric matrix, the analytical method used was both highly selective and sensitive. These two properties were obtained by associating chromatography with ion trap tandem mass spectrometry (GC-ITD (MS/MS)). To develop this method, a comparison between the two ionization modes (electron impact and positive-chemical-ionisation) in single-MS was first conducted to choose the parent ions of the five target analytes, i.e. atrazine, desethylatrazine, deisopropylatrazine, terbuthylazine and desethylterbuthylazine. Then, a MS/MS method was optimised by parameters such as the radio frequency storage level and the collision-induced dissociation excitation voltage. Finally, a last step enabled the development of a calibrating program based on the quantification of daughter ions. With this analytical procedure, the detection limits varied between 0.8 and 15 pg m(-3) depending on the compounds under study. This method was tested with success for four atmospheric samples collected in Strasbourg (France) in which four of the five target compounds were detected.