Journal of Hazardous Materials 185 (2011) 1156–1161 Contents lists available at ScienceDirect Journal of Hazardous Materials journal homepage: www.elsevier.com/locate/jhazmat Decreasing polycyclic aromatic hydrocarbons emission from bitumen using alternative bitumen production process Y. Rasoulzadeh a,b , S.B. Mortazavi b,∗ , A.A. Yousefi c,d , A. Khavanin b a Department of Occupational Health, Tabriz University of Medical Sciences, P.O. Box 5166614711, Tabriz, Iran b Department of Occupational and Environmental Health, Tarbiat Modares University, Tehran, Iran c Iran Polymer and Petrochemical Institute, P.O. Box 14965-115, Tehran, Iran d Institute for Color Science and Technology, P.O. Box 16765-654, Tehran, Iran article info Article history: Received 20 April 2010 Received in revised form 1 September 2010 Accepted 8 October 2010 Available online 16 October 2010 Keywords: Polycyclic aromatic hydrocarbons Emissions Occupational exposure Bitumen modification Control abstract In 1988, the National Institute for Occupational Safety and Health (NIOSH) recommended that bitumen fumes should also be considered a potential occupational carcinogen and management practices such as engineering controls should be implemented. Changing the production process of bitumen, as a source control method, was investigated in our study. For the first time, a novel alternative process was used to produce paving grade bitumen with decreased PAH emissions as well as improved bitumen performance grade (PG). Post-consumer latex and natural bitumen (NB) were used as additives to obtain 60/70 modi- fied bitumen directly from the vacuum bottom (VB) without any need for air-blowing. The emissions were produced by a laboratory fume generation rig and were sampled and analyzed by GC-Mass and GC-FID as described in NIOSH method 5515. The PG of the resulting modified 60/70 bitumen in this study covers a wider range of climatic conditions and has higher total resistance against deformation than conventional 60/70 bitumen. The total PAH emissions from modified 60/70 bitumen (100.2619 ng/g) were decreased approximately to 50% of PAHs emitted from conventional 60/70 bitumen (197.696 ng/g). Therefore, it is possible to obtain modified bitumen with lower PAH emissions and better quality than conventional bitumen via additives and without air-blowing. © 2010 Elsevier B.V. All rights reserved. 1. Introduction Bitumen is a dark brown to black petroleum-derived binder that is used for paving (87%), roofing (11%), water proofing, bitumen-based paints, among other applications (2%) [1]. Bitumen composition is divided into four generic groups (SARAs): saturates, aromatics, resins, and asphaltenes [2,3]. The bitumen composi- tion and consequently the physical and mechanical properties of bitumen vary depending on crude oil sources and their refining processes [2]. Due to high temperature processing of bitumen in refineries (up to 288 ◦ C) and bitumen-contained materials (such as roofing products and asphalt) in factories (160–250 ◦ C), the bitu- men fumes and vapors may be released, and as a result, workers involved in these processes are exposed to emissions. Bitumen fumes and vapors may contain very small quantities of polycyclic aromatic compounds (PACs), which are comprised of polycyclic aromatic hydrocarbons (PAHs). ∗ Corresponding author. Tel.: +982182883825; fax: +982182883825. E-mail addresses: rasoulzadehy@yahoo.com (Y. Rasoulzadeh), mortazav@ modares.ac.ir (S.B. Mortazavi). Some PACs and derivatives are known to have mutagenic and carcinogenic effects, and certain 4- and 5-ring PACs (i.e., benz[a]anthracene, chrysene, and benz[a]pyrene) are mutagenic and possibly carcinogenic [4]. The carcinogenicity of bitumen fumes has been investigated in several epidemiological studies, and some of these studies have suggested that exposure to bitu- men fumes increases the risk of developing lung cancer as well as other cancers [5]. The International Agency for Research on Cancer (IARC) have evaluated the carcinogenicity of bitumen and clas- sified air-refined bitumen as a possible human carcinogen (IARC group 2B) [6,7]. In 1988, NIOSH (National Institute of Occupational Safety and Health) advised asphalt fumes should also be considered a potential occupational carcinogen and governing practices such as engineering controls should be employed [8]. Several laboratory and field studies have investigated the qual- ity and quantity of bitumen emissions and their occupational and environmental impacts [9]. Also, some descriptive studies have investigated PAH emissions from asphalts produced with conven- tional and modified paving grade bitumen. NIOSH investigated the occupational exposures and acute health effects of crumb-rubber modified (CRM) asphalt in comparison with conventional asphalt [10]. This study reported increased concentrations of emissions in personnel breathing zones for CRM asphalt. Virpi Vaananen 0304-3894/$ – see front matter © 2010 Elsevier B.V. All rights reserved. doi:10.1016/j.jhazmat.2010.10.026