Characterization of an asphalt fume generation system and determination of fume compositions at simulated road paving conditions.
Wang-J; Frazer-DG; Goldsmith-T; Tomblyn-S; Simpson-J; Stone-S; Afshari-A; Lewis-DM; Castranova-V; Siegel-PD
Toxicologist 2001 Mar; 60(1):20-21
A highly sensitive, selective, and reliable analytical method has been developed and validated for characterization of asphalt fume generated under road paving conditions. A new approach was developed utilizing a microflow liquid chromatogram (LC) coupled to atmospheric pressure chemical ionization (APCI) of quadrupole/time-of-flight mass spectrometry (Q-TOF MS). A dynamic asphalt fume generation system was modified to provide consistent test atmospheres at simulated road asphalt paving conditions. Characterization of the asphalt fume test atmospheres included (1) determination of the uniformity of the aerosol distribution within the generator and exposure chamber; (2) quantitative detection of total extractable asphalt fume content by electron ionization of isotope dilution GC-MS; (3) use a photo ionization detector (PID) for on-line monitoring; and (4) identification of individual priority polycyclic aromatic hydrocarbons (PAHs) in the asphalt fume by selected ion monitoring GC-MS, and further clarification of important PAH by coupling microflow LC to Q-TOF MS. Total extractable asphalt fume components were quantified over the 5 day exposure. Sixteen individual priority PAHs were monitored and identified. These PHA's were detected at a trace level on filter fractions. By coupling microflow LC to APCI of Q-TOF MS, the new approach of collision-induced disassocation of fragmentation pathway leading to a characteristic fragmentation pattern for selected target analytes was used to further clarify the trace amount of PAHs present in simulated road paving asphalt fumes. These results demonstrate that asphalt fume compositions can be characterized and individual priority PAHs can be identified at trace levels using this developed method. Such a method is suitable for support of simulated occupational exposure for inhalation toxicity studies.
Asphalt-fumes; Fumes; Analytical-methods; Ionization; Aerosols; Exposure-chambers; Occupational-exposure; Inhalation-studies
The Toxicologist. Society of Toxicology 40th Annual Meeting, March 25-29, 2001, San Francisco, California