Laboratory Generation and Evaluation of Paving Asphalt Fumes

Abstract

A novel laboratory asphalt fume generator was developed and validated against fumes collected on personnel monitors from field paving sites and above paving asphalt storage tanks. Once the apparatus was validated, fumes were generated from eight core Strategic Highway Research Program (SHRP) single crude asphalts, as well as from synthetically produced positive and negative control asphalts. The fumes were characterized using a number of analytical techniques, including gas chromatography/mass spectrometry, gas chromatography with flame ionization detection, UV/fluorescence, and a short-term bioassay called the modified Ames test. For comparison purposes, the same methods were applied to fume condensate preparations from the National Institute of Occupational Safety and Health (NIOSH) animal skin-painting studies. On the basis of the chemical and biological tests, these SHRP asphalt fumes were found to have a lower carcinogenic potential than a NIOSH fume fraction found to be noncarcinogenic in the NIOSH studies.