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Cooking exhausts may contribute significant organic compounds to the atmosphere. It has been shown that trans , trans -2,4-decadienal ( tt -DDE) is an important toxic compound in cooking oil fumes (COF). In this study, the emissions of tt -DDE were quantified in both gaseous and particulate phases of three kinds of restaurant exhausts (Chinese, western and barbecue). Samples of exhausts were collected with a sampling system meeting the criteria of US EPA Modified Method 5. The tt -DDE was analyzed by HPLC–MS/MS. The results indicate that the emission factors of tt -DDE in terms of μg customer −1 were in sequence: barbecue (1990)>Chinese (570)>western (63.8). The average proportion of tt -DDE in the particulate phase of the exhausts was 83% for the 16 investigated restaurants. Evidently, the majority of tt -DDE in the exhausts was in the particulate phase. There was no evident correlation found between phase distribution of tt -DDE and exhaust temperature in the restaurants investigated. The efficiencies of removal of particulate tt -DDE by air pollution control devices (APCDs) were assessed. The removal efficiencies of electrostatic precipitator (ESP), ESP and activated carbon in series, and wet scrubber were 64.2%, 86.3% and 71.3%, respectively.

The atmospheric particle size distributions of 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) between 0.056 and 100 μm in aerodynamic diameter (Dp) were measured at two sampling sites during January 2002. These sites were 1.1 and 2.1 km downwind from a municipal incinerator in central Taiwan, respectively. Size-segregated atmospheric particles were simultaneously collected by means of a cascade impactor and a rotary impactor. The results showed that PCDD/Fs were associated with the full size range of atmospheric particles. More than 80% of the ΣPCDD/Fs and toxic equivalents (TEQs) were found to be associated with fine particles of aerodynamic diameter, Dp 2.0 μm). As for PCDDs, however, a relative enrichment of the less chlorinated congeners on coarse particles was found only at the farther sampling site (2.1 km).

Heavy metals are one of the concerned pollutants emitted by the municipal waste incineration system (MWIs). The objective of this study was to evaluate the potential impact on local airborne metals from the emissions of an MWI. Aerosol samples were simultaneously collected at eight different sites around the municipal waste incinerator using PS-1 sampler. The concentrations of 16 elements (Mg, Al, Fe, Cu, Zn, Pb, Ti, V, Cr, Mn, Co, Ni, As, Cd, Ba and Hg) were quantified by inductively coupled plasma-mass spectrometry (ICP–MS) and atomic absorption spectrometer (AA). The profiles of the 16 metals in the surroundings of a municipal incinerator in central Taiwan were compared with those of the emission sources. The results showed that the profiles of multiple metals obtained at all sampling sites were similar to those emitted from the MWI stack. These findings suggested that the local airborne metal pollutants might probably derive from the stack emission of the MWI. Using cadmium as an index metal, it was found that the metals like Mg, Ti, V, Cr, Mn, Co, Ni, As, and Hg are highly influenced by the stack emission from the municipal incinerator. Moreover, the ratio of other metals to Cd that were increased with the distance from the incinerator. This might be due to the additional sources contributed to airborne metals following the emission from the incinerator and a difference in particle size of each particle-bound metal.