Kühn M, Welsch H, Zahnert T, Hummel Thomas
Flugmedizinisches Institut der Luftwaffe, Abteilung Flugphysiologie, Königsbrück.
Laryngorhinootologie. 2009 Sep;88(9):583-6. doi: 10.1055/s-0029-1202368. Epub 2009 Mar 18.
The human sense of smell seems to be influenced by the surrounding barometric pressure. These factors appear to be especially important during flights, for example, in order to recognize the smell of fire etc. Thus, questions are whether pilots or passengers exhibit an impaired smell sensitivity when tested at moderate heights, or, whether changes in humidity would affect the sense of smell.
Using climate chambers, odor discrimination and butanol odor thresholds were tested in 77 healthy normosmic volunteers (5 female, 72 male; aged 25+/-8 years from 18 up to 53 years) under hypobaric (2 700+/-20 m, 20 degrees C+/-1 K, rh=50+/-5%) and hyperbaric, (10+/-0.5 m (2 bar)) and different humidity conditions (30 vs. 80%, 20 degrees C+/-1 K, normobaric). During all conditions cognitive performance was tested.
Among other effects, olfactory sensitivity was impaired at threshold, but not suprathreshold level, in a hypobaric compared to a hyperbaric milieu, and thresholds were lower in humid, compared to relatively dry conditions.
In conclusion, environmental conditions modulate the sense of smell, and may, consecutively, influence results from olfactory tests. During flight hypobaric conditions, mild hypoxia and dry air may cause impaired sensitivity of smell.
人类的嗅觉似乎会受到周围气压的影响。例如，在飞行过程中，这些因素似乎尤为重要，以便能够识别火灾等气味。因此，问题在于在中等高度进行测试时，飞行员或乘客的嗅觉敏感性是否会受损，或者湿度变化是否会影响嗅觉。
利用气候舱，在低压（2700±20米，20℃±1K，相对湿度=50±5%）、高压（10±0.5米（2巴））以及不同湿度条件（30%与80%，20℃±1K，常压）下，对77名健康的嗅觉正常志愿者（5名女性，72名男性；年龄25±8岁，18至53岁）进行气味辨别和丁醇气味阈值测试。在所有条件下均对认知能力进行了测试。
在其他影响因素中，与高压环境相比，在低压环境下嗅觉敏感性在阈值水平受损，但在阈上水平未受损，并且与相对干燥的条件相比，在潮湿条件下阈值更低。
总之，环境条件会调节嗅觉，并可能继而影响嗅觉测试结果。在飞行的低压条件下，轻度缺氧和干燥空气可能会导致嗅觉敏感性受损。
