This study compared the stability of odor compounds in three different types of polymer sampling bags. Tedlar, PET (polyethylene terephthalate) and aluminized polyester bag were used. A sample was collected from the interior of a new automobile which was parked in an outdoor parking lot. It was found that the Tedlar bag showed lower stability for odor active compounds than the PET bag. Meanwhile, the PET bag had good stability for odor compounds compared to the aluminized polyester bag. The PET bag showed a stability for the molecules smaller than toluene that was comparable to the canister, but showed a lower recovery for molecules bigger than C7. The FID signal of the sample in the PET bag was reduced by 1.7times after 3days storage compared to 24 h storage. The number of detected odor active compounds was reduced by half, and odor intensity was also decreased by 2~3 degrees. Considering the factors of repeated use, usability and price, a PET bag covered with a black plastic bag was the most appropriate approach for odor sampling in an automobile interior.

In this study, odor active compounds, emitted from food waste composting facility, were analyzed and their contribution degree were evaluated. Sample gases were collected at the inlet and outlet of scrubbing tower and bio-filter, respectively. The odor active compounds were separated by GC/FID/Olfactometry (GC/FID/O) and identified by GC/MS. Odor intensity and SNIF (Surface of Nasal Impact frequency) were used to evaluate contribution of each odor active compound. It was possible to calculate contribution rate (%) and reduction rate (%) of odor active compounds using analysis and evaluation of contribution degree of odor active compounds. As a result, the compounds showing the high contribution degree were fatty acids, ketones at inlet and aldehydes, ketones at outlet. Deodoring equipment of food waste composting facility appeared effective for the reduction of aldehydes, ketones but appeared week for the reduction of aldehydes. Although scrubbing tower and bio-filter could reduce 7 times of odor level, the outlet gases had odor dillution ratio of 3000, which exceed the allowable levels of Korean guideline by 6 times.

Volatile fatty acids (VFAs) are malodor compounds which are produced from the decomposition of animal or plant species. It is very difficult to detect VFAs due to their strong adsorptive properties. In this study we develop an analytical method using headspace-GC/FID with an alkali-impregnated filter sampling. The addition of NaCl and H₂S0₄ makes the salt-out and pH-lowering effect, respectively. The high boiling points (141~185℃) and vapor pressures require a high temperature and long heating time for the standard sample in vials to reach an equilibrium. The analytical response was highest when the absolute quantity in the sample was 5 mL in a 22 mL vial. The addition of NaCl for the salt-out effect can give a higher sensitiviry by a factor of 1.1~4.2 than that of Na₂SO₄. The mass amount of 4.6 g of NaCl can result in a higher sensitivity, which is higher than the supersaturated solubility of 4.2 g. The concentration of H₂SO₄ is as low as 2% (v/v). When the concentration range is 8.3 -562.1 ppb, a coefficient of R²~0.99 can be obtained for the five VFAs samples. The analytical errors in a reproducibility test are less than 10% and the detection limit is estimated to be 0.05~0.1 ppb. Our headspace-GC/FID analytical method can be utilized to effectively detect the five kinds of VFAs which shall be restricted in Republic of Korea from the year of 2010.

In this study, the TVOCs and odor active compounds emitted from 3 PVC and 5 natural wallpapers were analyzed. The emitted odor intensities and characteristics of the wallpapers were estimated using air dilution sensory and direct olfactory methods. The emissions of TVOCs were measured using the SPME-cryogenic emission test method, which was modified from the RAL-GZ 479 method, which is used in Germany to evaluate the quality of wallpapers. It was found that there was no significant correlation between the emissions of TVOCs and the odor concentration. However, a correlation (0.57) was found between the emitted VOCs and the odor concentration of the low molecular weight compounds, which have strong volatilities, ranging from n-C6 to n-C10. For all 8 wallpapers, vinegar like odor was commonly perceived, with acetic acid identified as the main odor active compound withinthe odor. Benzaldehyde and esters, such as ethyl acrylate and n-butyl acrylate, were identified as odor active compounds, which were expressed as having rubber like smells by the panelists. These results indicate that odor should be included as a domestic regulation for the pollutants emitted from building materials. The identification of odor active compounds emitted from building materials could be useful in the production of eco-environment products.

In this study, alkali impregnated filter sampling method was considered for VFAs in ambient air. When KOH concentration was 0.5 N and sampling flow velocity was 5~10 L/min the sampling efficiency was higher than 90 percent. More than 3 minute shaking make the sampled filter to be suspended in the 22.3 mL Vial. Alkali impregnated filter sampling method showed more than 4 times higher response compared to alkali solution sampling method, when the sample was analysed by headspace-gas chromatography. Five kinds of volatile fatty acids (propionic acid, i-butyric acid, n-butyric acid, i-valeric acid, valeric acid) were detected within 1.0~9.8 ppbv in the cow shed by alkali impregnated filter method and headspace gas chromatography. The alkali impregnated filter method was the most suitable sampling method for ambient volatile fatty acids with headspace gas chromatography analysis.

In this study, we identified the odor active compounds among MVOCs (Microbial Volitile Organic Compounds) emitted from Geotrichum sp. which was previously identified as the main kinds of mold in indoor air. To sample the odor active compounds emitted from Geotrichum sp. while metabolizing, head space-solid phase microextraction (HS-SPME) method, which is well known for sampling odorants, was used. GC/Flame Ionization Detector/Olfactometry was used to identify main odor active compounds. GC/Atomic Emission Detector was used to identify if some compounds had atoms like oxygen, nitrogen, sulfur which are typically found from odorants. GC/Mass Spectrometry was used to identify the odorants. Finally, Retention Index (RI) of each system was verified. In this study, hydrogen sulfide, methanthiol, 1-butanol, carbon disulfide, dimethyl sulfide, dimethyl disulfide, S-methyl thiobutyrate, dimethyl trisulfide, geosmin were identified as MVOCs. Among them, identified main odor active compounds were dimethyl disulfie and dimethyl trisulfide which induce ordure smell and geosmin which induce moldy, earthy smell.

PM10 concentrations were measured in underground stores located in 4 major cities, Chunchon, Wonju, Donghae and Sockcho, in Kangwon-Do using scattering light integrated type digital dust indicator. Personal exposure to PM10 for two women(housekeeper and graduate student) and a man(undergraduate student) were measured also. The dimensional conversion factors for mass concentrations(K) showed some difference among underground stores which were 2.0, 2.7, 3.4, 2.6 ㎍/㎥·CPM in chunchon, Wonju, Donghae and Sockcho, respectively. Average PM_10 concentrations at underground stores were 178 ㎍/㎥ in Chunchon, 141 ㎍/㎥ in Wonju, 125 ㎍/㎥ in Donghe and 59 ㎍/㎥ in Sockcho. The portion of PM10 in total suspended particles was about 50∼60 % as weight. The exposure of graduate student, housekeeper and undergraduate to PM10 during 12 hours were 1004.3 (㎍/㎥)·hr, 907.0 (㎍/㎥)·hr and 691.2 (㎍/㎥)·hr, respectively. Personal exposure to PM10 showed very different according to their activity pattern and they had more than 90 % of their PM10 exposure at indoor environment.