Gas/Particle Partitioning of Dioxins in Exhaust Gases from Automobiles

Abstract

This study investigates distributions of polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran (PCDD/F) congeners in the exhaust gases of gasoline-and diesel-fueled vehicles. 6 sport utility vehicles (SUVs), 6 diesel passenger vehicles (DPVs), and 3 heavy duty diesel vehicle (HDDV) were examined using chassis dynamometer tests for measuring vehicular dioxin emissions. The mean PCDD/F I-TEQ emission factors were 0.101, 0.0688 and 0.912 ng I-TEQ/km for the SUVs, DPVs and HDDV, respectively. Highly chlorinated congeners dominated both gaseous and particulate phase PCDD/Fs. The major contributors of gas-phase PCDD/F I-TEQ for the SUVs, DPVs, and HDDV were 2, 3,4,7, 2,3,7, and 2,3,4,7, respectively; however, 2,3,4,7,8-PeCDF was the major contributor in particulatephase PCDD/F I-TEQ of these vehicles. The particulate-phase PCDD/Fs was responsible for 78.0, 90.3 and 71.1% of total PCDD/Fs for the SUVs, DPVs, and HDDV, respectively. Therefore, the control of particulate matter is more critical than that of gaseous pollutants for reducing PCDD/F emissions from automobiles.

Measurements and Correlations of MTBE and BETX in Traffic Tunnels

“…The X/E ratio was calculated for each sampling site, and the geometric mean and geometric standard deviation of the X/E ratios for TC, DBP and NT are 2.9 and 1.3; 2.8 and 1.3; and 2.3 and 1.2, respectively, were determined. In fact, characteristics of traffic-related VOC emissions are different from those of traffic-related aerosols (Chakraborty, A. and Gupta, T. 2010;Cheng et al, 2010;Chuang et al, 2010aChuang et al, , 2010bPawar et al, 2010;Shen et al, 2010;Wu et al, 2010).…”

PCDD/F emissions from light-duty diesel vehicles operated under highway conditions and a diesel-engine based power generator

“…The results vary from 7.9 to 12, 0.71 to 0.78 and 0.46 to 1.3 ng I-TEQ/km for the light duty vans RK1, RK2 and the passenger car, respectively. These values are slightly higher or on the same order of the highest available published data: 1.3-9.5 ng I-TEQ/km [7], 0.72-9.5 ng I-TEQ/km [9], 0.91 ng I-TEQ/km [24] and 1.7 ng I-TEQ/km [26]. Tables S7 and S8 of Concerning test 3 (cold conditions) and test 4 (warm conditions), which were carried out 2 days apart, it can be observed that the emission of PCDD/Fs was higher in the former than the latter.…”

“…In all runs, the concentration of PCDDs in exhaust gases exceeds that of PCDFs. Table S3, we see that several authors [17,19,24,27] In all runs, the PCDD contribution to I-TEQ is greater than that of the PCDFs. Figure 2 The TEQ-weighted congener distribution of the diesel passenger car is shown in Figure 3 Moreover, RK2 belongs to Euro 4 whereas RK1 belongs to Euro 3.…”

“…No reference works dealing with on-road samplings in passenger vehicles have been found. Table S3 of the supporting information summarizes some published data concerning the main congeners (without toxicity factors), the congeners that contribute to the total toxicity I-TEQ (taking into account the toxicity factors), and the percentage x 100 of Page 5 of 32 A c c e p t e d M a n u s c r i p t 5 PCDFs/(PCDFs+PCDDs) without and with TEF factors [2,3,6,8,[15][16][17][18][19]21,22,24,26,27,[29][30][31][32][33].…”

Comparison of Emission of Dioxins and Furans from Gasohol- and Ethanol-Powered Vehicles

“…Chuang et al, 30 using the same driving cycle than this study, obtained average emission of 101 pg I-TEQ km À1 and standard deviation of 64.3 pg I-TEQ km À1 . Marklund et al, cited by Geueke et al, 31 estimated that the emission rate of total PCDD/F in catalyzed vehicles fueled with nonleaded gasoline was of the order of 0.36 I-TEQ pg km À1 .…”