The evaluation of petroleum-based paving asphalts as a possible source of heavy metal pollution in soils and water, as well as the determination of combustion parameters—smoke mass and particle size distribution, and sulfur dioxide and oxides of nitrogen during controlled burning—represented the main goals of this study. Special consideration was given to the changes in combustion behavior, smoke components, and heavy metal content introduced by the addition of tire rubber to the paving asphalt samples. The different analytical techniques applied were conducted on samples of pure asphalt cement (including different brands and grades), samples of asphalt rubber (with concentrations of 4%, 10%, and 18% of tire rubber), and samples of asphalt concrete taken from two different locations in the city of College Station, Texas. Instrumental neutron activation analysis (INAA) was used to identify and quantify the heavy metals present in the asphalts. Zinc, manganese, and vanadium were the most prevalent metallic constituents. Zinc was generally found in the highest concentrations while manganese was present in all the samples analyzed. The study showed increasing levels of zinc (range of 1,040 ppm to 2560 ppm) with corresponding higher levels of tire rubber content. Total absence of nickel in all of the samples tested implies the need for longer INAA radiation times and/or the need to resort to other analytical methods such as atomic absorption since both nickel and vanadium are present in the porphyrin complex structures in the crudes from which the asphalts originated. The evaluation of different samples of asphalt under controlled combustion showed that more than 90% of the smoke particles emitted by all the samples were less than 10 μm in diameter and, thus, are easily inhaled deep into the human respiratory system. It was also observed that the amount of smoke generated by samples of asphalt containing rubber was up to 43% higher than the amount of smoke produced by samples of the same brand and grading but with no tire rubber present. The analysis of the gaseous smoke components on a Bachrach Model 300 NSX Combustion Analyzer showed very low levels of NOxbut higher amounts of SO2. The latter SO2levels were in the expected range based on the common practice of using sour crude oils (approx. 1% sulfur) for asphalt production, but they were less than the expected sulfur content in rubber after the vulcanization process. Nevertheless, the relative concentrations of SO2gave approximate yield values as high as 7.42 L of SO2/kg asphalt. Depending on prevailing wind conditions this yield could present a threat to human life, such as during a fire in an asphalt tank or an asphalt-processing facility, or during an accidental ignition of hydrocarbons on an asphaltic surface from an overturned or ruptured fuel delivery truck. The results of this study support the hypothesis that more attention should be given to the potential global pollutant effects of paving asphalts because of the enormous quantities utilized each year and their nonpermanence. Research regarding the environmental effects of using tire rubber as a paving additive also needs to be more rigorously addressed.