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Published on: September 13, 2024
Mexico City air pollution adversely affects olfactory function and intranasal trigeminal sensitivity
Marco Guarneros1, Thomas Hummel, Margaríta Martínez-Gómez
1Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México,AP 70228, CP 04510, Distrito Federal, Mexico.
Chemical Senses
|October 13, 2009
Summary
Big-city air pollution significantly impairs sense of smell and trigeminal sensitivity. Even healthy young adults in highly polluted Mexico City showed reduced olfactory function and trigeminal perception compared to a less polluted control group.
Area of Science:
- Environmental Health
- Neuroscience
- Sensory Science
Background:
- Limited understanding of urban air pollution's impact on olfactory and intranasal trigeminal systems.
- The intranasal trigeminal system contributes to chemosensory experiences like burning and pungent sensations.
Purpose of the Study:
- To investigate the effects of Mexico City's high air pollution on olfactory function.
- To assess the impact of air pollution on intranasal trigeminal sensitivity.
Main Methods:
- Comparison of olfactory and trigeminal sensitivity between 30 young adults from Mexico City and 30 from Tlaxcala (less polluted region).
- Utilized the Sniffin' Sticks olfactory test battery and a trigeminal perception test.
- Assessed odor detection (2-phenyl ethanol), odor discrimination, and odor identification.
Main Results:
- Tlaxcala residents detected odorants at significantly lower concentrations than Mexico City residents.
- Control subjects demonstrated significantly better odor discrimination abilities.
- Intranasal trigeminal sensitivity was significantly higher in the control group.
Conclusions:
- Mexico City's air pollution demonstrably impairs olfactory function in young adults.
- Air pollution negatively affects intranasal trigeminal sensitivity, even in healthy individuals.
- Findings highlight the detrimental sensory effects of urban air pollution.
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