6 EXPERIMENTAL STUDIES .................................. 76
6.1 Genotoxicity .................................................. 76
6.1.1 Mutagenic Effects ........................................ 76
6.1.2 Chromosomal Aberrations .................................. 78
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6.1.3 DNA-Adduct Formation ................................... 79
6.1.4 Intercellular Communication ................................ 80
6.2 Carcinogenicity ................................................. 80
6.2.1 Roofing Asphalt Fume Condensates and Raw Asphalt ............ 80
6.2.2 Asphalt-Based Paints ...................................... 85
6.3 Conclusions .................................................. 86
6.3.1 Asphalt Fumes ........................................... 86
6.3.2 Raw Asphalt and Asphalt Paints ............................. 87
7 CONCLUSIONS ........................................ 89
7.1 Cancer Issues .................................................. 89
7.1.1 Characterization of Asphalt Fumes ........................... 89
7.1.2 Paving Asphalt ........................................... 90
7.1.2.1 Short-Term Assays ................................ 90
7.1.2.2 Human Studies ................................... 90
7.1.3 Roofing Asphalt .......................................... 91
7.1.3.1 Animal Studies ................................... 91
7.1.3.2 Human Studies ................................... 91
7.1.4 Exposures to Other Asphalt Products ......................... 92
7.1.4.1 Animal Studies—Raw Asphalt and Asphalt-Based Paint . . . 92
7.1.4.2 Human Studies ................................... 92
7.2 Noncarcinogenic Health Effects .................................... 92
7.3 Overall Conclusions ............................................. 94
7.4 Recommendations ............................................... 95
8 RESEARCH NEEDS ....................................... 97
8.1 Human Studies ................................................. 97
8.1.1 Cancer Studies ........................................... 97
8.1.2 Noncancer Studies ........................................ 97
8.2 Animal Studies ................................................. 98
8.3 Biomarker Studies ............................................... 98
8.4 Fume Characterization, Sampling, and Analytical Methods .............. 98
8.5 Control Technology ............................................. 99
8.5.1 Paving Operations ........................................ 99
8.5.2 Roofing Operations ....................................... 99
8.5.3 Waterproofing Operations .................................. 100
8.6 Training and Education Effectiveness ............................... 100
REFERENCES ............................................ 101
APPENDIX A: Uses and Applications of Asphalt ............................. 115
APPENDIX B: Summary of Occupational Exposure Data ....................... 119
APPENDIX C: Respirators ............................................... 132