Polycyclic aromatic hydrocarbons study and toxic equivalency factor (TEFs) in Tehran, IRAN

Abstract

Polycyclic aromatic hydrocarbons (PAHs) are toxic pollutants released by various urban combustion sources. Benzo[a]pyrene (BaP) is a representative member of the class of PAHs. Health risk assessment associated with inhalatory PAHs uptake is often estimated on the basis of the BaP concentrations in air. Atmospheric particulate PAHs concentrations were measured at five locations in Tehran, Iran. Sixteen PAHs were extracted from the airborne particles and analyzed by HPLC. Total PAHs concentrations (16 compounds) at five station Arjanteen, Enghelab, Azadi, Bahman, Haft Houz were respectively, 70.2, 96.5, 130, 79.1, 44.1 ng/m(3). The information obtain from the present study indicated that mean of human carcinogens are: benzo[a]antheracene (0.17-4.76 ng/m(3)), chrysene (1.74-3.62 ng/m(3)), benzo[b]fluoranthene (0-5.25 ng/m(3)), benzo[k]fluoranthene (0.32-1.72 ng/m(3)), benzo[a]pyrene (1.41-3.82 ng/m(3)), dibenzo[a,h]anthracene (0.33-2.13 ng/m(3)), and indeno[1,2,3-cd]pyrene (0.25-11.08 ng/m(3)). The development and the establishment of a toxicity equivalency factor (TEF) are used in the assessment of mixtures containing PAHs. The contribution of the carcinogenic potency of BaP alone is in the range of 49.6-76.3% of the total carcinogenic activity. The annual number of lung cancer cases (persons per million) among Tehran residents (population = 10 millions) attributable to these carcinogenic PAHs compounds in 2005 was estimated at 58 persons per million. In Tehran urban areas vehicular emission are the primary contributor to PAHs concentrations, with additional local contributors like industrials emissions.

Occurrence, distribution, sources and toxic potential of polycyclic aromatic hydrocarbons (PAHs) in surface soils from the Kumasi Metropolis, Ghana

“…Health risk assessment associated with PAHs uptake is often estimated on the basis of the BaP concentrations. BaP is the highest carcinogenic contributor in almost every study (Halek et al, 2008). The development and establishment of a toxicity equivalency factors (TEFs) are used in the assessment of mixtures containing PAHs.…”

Distribution and risk assessment of polycyclic aromatic hydrocarbons (PAHs) from Liaohe estuarine wetland soils

“…On the basis of large amount of previous studies, Long et al (1995) proposed effects range low (ERL) and effects range median (ERM) to evaluate the potential eco-risk of organic pollutants. Halek et al (2008) established a toxicity equivalency factor (TEF) to assess the risk of mixtures containing PAHs. In this paper, 16 PAHs, including naphthalene (Nap), acenaphthene (Ace), acenaphthylene (Acy), fluorene (Flu), phenanthrene (Phe), anthracene (Ant), fluoranthene (Flt), pyrene (Pyr), benzo(a)anthracene (BaA), chrysene (Chr), benzo(b)fluoranthene (BbF), benzo(k)fluoranthene (BkF), benzo(a)pyrene (BaP), indeno(1,2,3,cd)pyrene (Ind), dibenzo(a,h)anthracene (DBA), and benzo (g,h,i)perylene (Bpe), were measured to assess environmental risk by ERL/ERM and TEF method.…”

Seasonal variation in ambient PM mass and number concentrations (case study: Tehran, Iran)

“…Quite a lot of research has investigated Tehran's air pollution, especially those related to particulate matter (Halek et al 2004;Heidarinasab et al 2004;Hosseinpour et al 2005;Faryadi and Taheri 2009). Some other researches have evaluated Tehran's air pollution in the case of other pollutants such as polycyclic aromatic hydrocarbons (Halek et al 2008), volatile organic compounds (Jafari and Ebrahimi 2007), and trace elements (Vigeh et al 2006). All of these studies suggest that the mobile sources in Tehran play the major role in making the pollution in this city.…”