The ozonolytic decomposition of terpenes and terpenoids during sampling on Tenax is investigated in an artificial air system at ambient concentration levels. The detrimental effect of 8-150 ppbv ozone depends on the chemical structure of the compounds:  saturated terpenoids such as 1,8-cineole, camphor, and bornyl acetate are unaffected by ozone. The terpenes and terpenoids which containing one C-C double bond are slightly decomposed in the order camphene < β-pinene ≈ myrtenal < α-pinene < sabinene ≈ citronellal. The compounds containing two or more double bonds are significantly decomposed in the order d-limonene ≈ citral < linalool < β-ocimene < terpinolene << α-terpinene ≈ β-caryophyllene. For α-pinene, sabinene and d-limonene, their ozonolysis products are found on the tubes:  pinonaldehyde, 5-(1-methylethyl)bicyclo[3.1.0]hexan-2-one, and 3-(1-methylethenyl)-6-oxoheptanal. The analytical recoveries are significantly enhanced for many compounds when the sampling duration is reduced from 10 min to 30 s, explained by the time available for ozonolysis. A miniature ozone scrubber with multiple layers of MnO(2)-coated copper nets was developed and thoroughly tested. The optimal number of plies is found to be 8, which ensures quantitative recoveries for all test compounds except α-terpinene, β-caryophyllene, citral, and citronellal. The results that are reported here call into question previous data on terpenes and terpenoids and/or their oxidation products where measurements have been carried out without the prior removal of ozone.

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The present investigation, carried out as a case study in a typical major city situated in a European coal combustion region (Krakow, Poland), aims at quantifying the impact on the urban air quality of residential heating by coal combustion in comparison with other potential pollution sources such as power plants, industry, and traffic. Emissions were measured for 20 major sources, including small stoves and boilers, and the particulate matter (PM) was analyzed for 52 individual compounds together with outdoor and indoor PM10 collected during typical winter pollution episodes. The data were analyzed using chemical mass balance modeling (CMB) and constrained positive matrix factorization (CMF) yielding source apportionments for PM10, B(a)P, and other regulated air pollutants namely Cd, Ni, As, and Pb. The results are potentially very useful for planning abatement strategies in all areas of the world, where coal combustion in small appliances is significant. During the studied pollution episodes in Krakow, European air quality limits were exceeded with up to a factor 8 for PM10 and up to a factor 200 for B(a)P. The levels of these air pollutants were accompanied by high concentrations of azaarenes, known markers for inefficient coal combustion. The major culprit for the extreme pollution levels was demonstrated to be residential heating by coal combustion in small stoves and boilers (>50% for PM10 and >90% B(a)P), whereas road transport (<10% for PM10 and <3% for B(a)P), and industry (4-15% for PM10 and <6% for B(a)P) played a lesser role. The indoor PM10 and B(a)P concentrations were at high levels similar to those of outdoor concentrations and were found to have the same sources as outdoors. The inorganic secondary aerosol component of PM10 amounted to around 30%, which for a large part may be attributed to the industrial emission of the precursors SO2 and NOx.