Farah Halek - Materials & Energy Research Center (merc), P. O. Box ۱۴۱۵۵-۴۷۷۷, Tehran, Iran
Ali Kavousi - Materials & Energy Research Center (merc), P. O. Box ۱۴۱۵۵-۴۷۷۷, Tehran, Iran

Tehran’s residents suffer a critical air pollution problem due to carbon monoxide, particulate matter and toxic air pollutants such as benzene and methyle tertiary butyl ether (MTBE). The fuel additive MTBE is a primary constituent in reformulated gasoline, accounting for approximately 10 - 15 % which of the reformulated fuels. MTBE and Benzene have accumulated sufficient evidence as human carcinogens. In order to evaluate the levels of these two air toxic pollutants in the tehran, ambient air samples were collected in sorbent tubes and analyzed with a gas chromatograph according to procedures described in the NIOSH method. Twenty different sites located in the Tehran area selected for the sampling. Quality assurance was performed collecting duplicate samples which were analyzed in replicate to quantify the precision of air quality measurements. Mean air concentrations for MTBE and Benzene were 12 ppb (MTBE) and 10 ppb (Benzene) in a urban area having low traffic; and 1000 ppb (MTBE) and 1050 ppb (Benzene) in the central area having high traffic. Results in Tehran’s atmosphere demonstrate a direct relationship between traffic density and level of human exposure to these pollutants.

MTBE, Benzene, Fuel Additive, Vehicle emission, Tehran air pollution