Odor problems in urban areas have become a common cause of public complaints. In order to gain a better understanding of odor problems, we investigated the emission characteristics of odorants originating from manholes (n=22) and stormwater catch basins (n=48) (SCBs) around Wangsimni station in Seoul. To this end, concentrations of H2S and NH3 were measured after arbitrarily dividing the whole study area into five different districts. Our measurements were made to allow comparisons between three different criteria: (1) manholes vs. SCBs, (2) temporal variation between morning vs. afternoon, and (3) water content in the sewer system. The average concentration of H2S in manholes and SCB were 2.39 ppm and 0.81 ppm, respectively. In contrast, their NH3 counterparts were 1.86 ppm and 1.02 ppm, respectively. According to the contouring method made to identify spatial distribution characteristics, of odorants a relatively lowland site D was expected to work as a significant emission source in light of the transportation patterns of a sewer system. Moreover, higher concentrations of odorants were prevalent in the afternoon (as the prime time for commercial activities) relative to before noon. If concentration data are converted into odor intensity, H2S was the predominant component exerting controls on the odor pollution in these underground environments.

In this study, emission characteristics of odorants from boiled egg samples were measured through time between fresh and decayed status. Air samples released from boiled egg were collected and analyzed five different periods during the whole experimental period set for 9 days. The concentrations of reduced sulfur compounds (RSC), carbonyl compounds (CC), and NH₃ were generally higher than others like volatile organic compounds over the entire period. Among target compounds, the concentration of H₂S recorded the maximum value of 3.65 ppm immediately after boiling which indicates its maximum contribution as odorant in fresh stage. In addition, some odorants (i.e. CH₃SH, AA, PA, BA, and VA) were detected in the range of 7.52 to 50.8 ppb. Emission of most odorants generally decreased after 1 day of boiling, although their concentrations increased again after 3 days to reach the peak values after 6 days. The dilution-to-threshold (D/T) ratio measured by air dilution sensory test samples between fresh and decayed egg showed patterns similar to H2S. In addition, the result of correlation analysis indicated that there is a strong relationship (p＜0.01) between complex odor and H₂S.

In this study, a series of experiments were carried out to measure temporal stability of trimethylamine (TMA) in two different bag sampler types (polyvinyl fluoride bag (PVF) and polyester aluminum bag (PEA)) as a function of storage time. To this end, temporal variability of TMA was measured using its standard gas samples up to 4 days. For the purpose of comparison, storability of TMA was tested between PVF and PEA. To this end, standard gas samples were prepared at two concentration levels of 1 and 10 ppm. The results of this study indicate that the reduction of TMA levels generally increased with the extension of the storage time. Although both bag types showed moderate losses of TMA, differences between bag types (PVF and PEA) were likely to be less significant than those of concentration levels.

In this study, we evaluated the composition of smoke released from fish frying processes. We selected 4 fish types (mackerel (M), hairtail (H), croaker (C), and japanese mackerel (J)) which are commonly served in our daily diet and collected their smoke samples. The analysis was made to cover both toxic and hazardous volatile organic compounds (VOCs) that include benzene, toluene, p-xylene, methyl ethyl ketone, methyl isobutyl ketone, butyl acetate, and isobutyl alcohol. According to our analysis, the mean concentrations (ppb) of VOCs derived from all 4 fish types were 254.5 (benzene), 34.5 (toluene), 833.0 (MEK), 29.4 (MIBK). Benzene as the class one carcinogen was detected at fairly high levels from these fish smoke samples so as to exceed indoor emission standard. Considering that roasted fish is often included as one of the common diet items, we can confirm that the smoke released from cooking should be controlled to reduce the possibility of their exposure to human.