In this study, we examined a measurement method for low concentration odor in a nursing home. We used the measurement method for low concentration odor applied to the general atmosphere environment. It is possible that the quality of the original odor change in the process of concentrating the odor sample, which is adsorbed into adsorbent-filled tube. Then, we investigated the sensory evaluation values of odor in the nursing home on the spot, and we investigated the odor we brought back in the tube, in order to examine how these two samples are different from of each other.
The results were as follows.
1) In this investigation, we detected that some rooms had odor from building materials while in other rooms the odor from excretion was stronger. We got this result because the nursing home we studied had been recently built.
2) The building materials odor was stronger in the sampling odor we brought back in the tube than in the odor measured in the nursing home. This result is due to the fact that building materials odors can be brought back to the laboratory almost intact compare to odor from excretion.
3) On the contrary, the odor from excretion was measured stronger in the nursing home. One reason for this is when researchers evaluate odor intensity in the room, evaluation values are influenced by the sight of excretion. The other reason is the difficulty of preserving the odor of excretion in tube completely intact.

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Odor emitted from rocky shore in seashore environment was estimated as an amenity factor, and compared with results in previous studies. Field surveys reveal that odor becomes weaker as the sea level rises, and slightly stronger as the illuminance increases especially at low tide, and that hedonic tone is improved at higher illuminance regardless of the sea level. Sensory evaluation of marine algae odor shows that the existence of seawater prohibits odor perception, and that of light contribute to higher pleasantness. These results seem to be related to the increase of the intertidal zone at low tide and the acceleration of biological activity by sunlight as previous studies pointed out. Consciousness research shows that much people recognize, accept, and require odor at rocky shore, and that odor intensity and acceptability affect on the formation of people's consciousness.

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The purpose of the present study was to investigate the cognitive and learning effects on odor perception during intermittent, short-duration odor presentation. Odor was presented using an olfactometer, as developed by Kobal and colleagues. Anethole, an odor unfamiliar to most Japanese people, was presented 60 times per session, and the duration of each stimulus was 200 ms with 14800 ms separating stimuli. The time between sessions was 1 hr. In each session, participants were given a positive or negative description of the odor, and asked to continuously evaluate the odor intensity using a sliding lever connected to a data recorder. All participants were subjected to sessions of both positive and negative descriptions, but the order of the two sessions was randomly assigned. The study found no statistical difference between the positive and negative conditions in regards to the values of perceived odor intensity. There was a significant difference, on the other hand, between the intensity values in the first and second sessions, suggesting that the participants became habituated to (learned) the odor. The study indicates that the effect of learning surpassed the descriptive (cognitive) effect in an intermittent short-duration paradigm. A between-subject study design is required in order to further examine the cognitive effects.

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We produced low concentration thermal desorption tube for olfactory measurement in accordance with the manual published by the Environmental Ministry of Japan. This apparatus is with an accuracy of the target determination limit of the odor concentration 1 (i. e. odor index 0 ) by Triangle odor bag method. The measurement result obtained from this apparatus agreed well with the odor degree perceived in the field.
Also, the measurement result of the duplicate test with this apparatus proved high reliability of this apparatus regarding both concentration and quality of the odor. The apparatus can be applied to olfactory measurement at gas exhaust, for example, in cleaning plants and restaurants. We examined that this apparatus has higher capability of keeping concentration and quality of odor than that of the bag collecting method during a week length sample preservation test.

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