The cooking-generated particles are major indoor sources of air pollution. Recently, the performance of the range hood is focused on particle removal performance. Range hood with an auxiliary air supply system can improve the fine and ultrafine particles removal efficiency by making a supply air during cooking activities. The particles were measured in the experimental building by varying ventilation types. Only operating range hood during the cooking activities was not enough to reduce the cooking-generated particles. Despite operating range hood systems, fine and ultrafine particle concentrations were maintained when cooking was finished. The range hood with a make-up air supply system can reduce the indoor particle concentration below background conditions when those systems were operated after cooking. In this study, the assessment of cooking-generated particle removal efficiency of the range hood with an auxiliary air supply system was conducted. The removal efficiency of ultrafine particles showed trends similar to the removal efficiency of fine particles.
Outdoor air pollution with particulate matter has become more severe in Korea. Ambient particle concentration affects the indoor environment through various routes through building envelopes. In this study, we investigated particle exposure in residential buildings. Indoor and outdoor particle sources determined the indoor concentrations and particle exposure. This paper measured indoor particles and CO2 concentrations in two different apartment buildings and conducted the survey for 24 hours. The I/O ratio of the occupant awake period was higher than the asleep period. The I/O ratio in the awake period is 0.93-3.65, while the I/O ratio in the asleep period is 0.31- 0.76.Indoor peak events such as cooking or cleaning temporarily increase the I/O ratio and emit the indoor particle sources. Decay rate constant is 0.49-6.84 (1/h) in the indoor peak events during the operation of the exhaust hood and natural ventilation. The size range of 0.3-0.5 μm size is over half for the proportions of emitted particles (55.6%). Daily exposure is divided into indoor sources (45.2%) and outdoor sources (54.8%). We found the differences for the proportion of particle exposure. The ratio of daily exposure in particles for 0.3-0.5 μm size is 43.1 (indoor)/ 56.9 (outdoor) %. However, indoor sources are higher than outdoor sources for the ratio of daily exposure in particles for the 0.5-10.0 μm size.
This study was conducted to estimate the contents of heavy metals including lead, cadmium,arsenic and total mercury in alcoholic beverages in Korea. Concentration of Hg was analyzed by gold amalgamation method, using mercury analyzer, while concentration of Pb, Cd and As was analyzed by ICP-MS. Concentration (μg/kg) of heavy metal in fermented liquors were ; for Pb 9.9 ± 8.4(0~38.0), Cd 5.8 ± 4.9(0~5.4), As 28.6 ± 19.4(1~96.4),Hg 0.7 ± 1.2(0~10.6). Concentration (μg/kg) of distilled liquors were : for Pb 4.4 ± 5.7(0~29.3), Cd 2.0 ± 2.5(0~10.3),As 12.0 ± 17.0(0~95.6), Hg 0.2 ± 0.3(0~2.3). Concentration(μg/kg) of other liquors were ; for Pb 7.5 ± 5.1(0~13.7),Cd 5.8 ± 3.9(0.6~11.2), As 25.2 ± 39.0(0.5~103.3), Hg 0.3 ± 0.1(0.1~0.5). The present study showed that difference of the amount of constituent in a same category of food are not affect to the content of heavy metals among them. The residual levels of takju, yakju, sake, beer, fruit wine, soju, whiskey, brandy, general distilled liquor, liquor, other liquors are within the maximum levels, prescribed by Korea food code. It is given that heavy metal exposure of Pb,Cd, As, Hg from consumption of alcoholic beverages (takju, yakju, sake, beer, fruit wine, soju, whiskey, brandy, general distilled liquor, liquor, other liquors) are less than 0.03%, 0.06%, 0.01%, 0.01% (mean) in provisional tolerable weekly intake (PTWI) respectively, indicated by FAO/WHO.