Residential wood burning in an Alpine valley as a source for oxygenated volatile organic compounds, hydrocarbons and organic acids

During a 3-week campaign in November/December 2005, 21 selected oxygenated volatile organic compounds (OVOCs), 19 non-methane hydrocarbons (NMHCs) and 11 low molecular weight organic acids were measured in Roveredo, a village in the Mesolcina valley in Southern Switzerland. In this region, the majority of the houses are heated with wood and the particulate matter is dominated by residential wood burning emissions. Markers in the aerosol mass spectra and carbon monoxide (CO) were used as indicators of domestic wood combustion while nitrogen oxides (NOx) were used as tracers for traffic emissions. The main source for most of the OVOCs, NMHCs and acids in this valley was assessed to be residential wood burning, except for trimethylbenzene (TMB), methylbutenol (MBO) and isopropanol. Comparisons for the NMHCs and OVOCs were made with measurements in Zürich, the largest city in Switzerland. These comparisons indicate that especially methanol, 1,3-butadiene, acrolein, methacrolein, methylacetate and methyl vinyl ketone (MVK) were strongly enhanced in Roveredo due to residential wood burning. The carcinogenic substance 1,3-butadiene shows higher concentrations in Roveredo than in Zürich, while benzene concentrations are similar at both locations. We provide a compilation of the VOC/CO ratios of the domestic wood burning dominated VOCs at Roveredo and a comparison to previously published emission ratios from wood stove studies.