Seasonal Variation and Gas/Particle Partitioning of PCBs in Air from Central Urban Area of an Industrial Base and Coastal City -Tianjin, China

摘要: ABSTRACTThe 26 air samples were collected from Tianjin urban areas July 2010 to May 2011 for the analysis of 86 PCB congeners investigate gas/particle partitioning PCBs. The total PCBs concentration (in pg/m3) ranged 31.28 650.33 (mean: 273.77) and showed a significantly seasonal variation as summer > autumn spring winter. Gas accounted 80.79% fraction each gas homolog increased with decreasing chlorine atoms. contribution strong (94.07%) (78.91%) (78.19%) winter (56.02%). Tri-, tetra- penta-PCBs predominantly homologs in atmosphere. natural logarithm partial pressure well correlated inverse absolute environmental temperature (R = 0.79). steep slope –4933.64 obtained Clausius–Clapeyron (C.C) plot indicated influence local sources. In generally, C.C slopes surface-air exchange enthalpy (∆HSA) different increasing particle bound underestimated PL0 10–3.85 Pa overestimated < by Junge-Pankow model. particle/gas coefficients (log KP) respective sub-cooled vapor pressures PL0) 0.72) octanol-air partition coefficient KOA) 0.77). log KP against KOA plots –0.44 0.48, deviated expected –1 +1 equilibrium state partitioning, possibly explained emission particles industries other TEQ concentrations (fg/m3) 12 dioxin-like 35.628 612.796 mean value 144.878.