| Abstract
| - Emissions from residential fireplace and woodstoveappliances burning fuels available from the San FranciscoBay area were sampled for polychlorinated dibenzodioxinsand dibenzofurans (PCDDs/Fs), polychlorinated biphenyls(PCBs), hexachlorobenzene (HxCBz), particulate matter (PM),polycyclic aromatic hydrocarbons (PAHs), oxygenatedPAHs, and the monosaccharide levoglucosan. Emissionfactors for these pollutants were determined, the first knowncharacterization of this extent. Common California naturalfirewoods and manufactured artificial logs were testedunder operating conditions intended to reflect domestic usepatterns in the Bay area, which are primarily episodicburning for aesthetic reasons. Emission factors weredetermined by fuel type, fuel weight, mass emission rates,and energy output, highlighting differences between fueland combustion facility type. Average PCDD/F emissionsfactors ranged from 0.25 to 1.4 ng toxic equivalency (TEQ)/kg of wood burned for natural wood fuels and 2.4 ng TEQ/kg for artificial logs. The natural wood emission factorsare slightly lower than those which had been estimated forthe U.S. inventory. Background-corrected PCBs emittedfrom woodstove/oak combustion (8370 ng/kg) are 3 ordersof magnitude higher in mass than total PCDDs/Fs; however,their toxicity (0.014 ng TEQ/kg) is significantly lower. HxCBzemission factors varied from 13 to 990 ng/kg and werelikely fuel- and appliance-specific. Relative PAH concentrations of particle-phase compounds and emission factorswere consistent with others' findings. A total of 32 PAHcompounds, ranging in concentration from 0.06 to 7 mg/kg, amounted to between 0.12 and 0.38% of the PM mass,depending on the wood and facility type. Preliminaryanalyses suggest relationships between wood combustionmarkers and PCDD/F levels.
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