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Published on: March 18, 2019
Intranasal effects in chemically sensitive volunteers: an experimental exposure study
Christoph van Thriel1, Gerhard A Wiesmüller, Meinolf Blaszkewicz
1Leibniz Research Centre for Working Environment and Human Factors, Institut für Arbeitsphysiologie an der Universität Dortmund, Ardeystrasse 67, D-44139 Dortmund, Germany.
Chemicals like ethyl benzene and MEK did not trigger inflammatory responses in nasal passages. Individuals with chemical sensitivity reported irritation, but objective measures showed no significant changes, suggesting lower irritant potency than expected.
Area of Science:
- Environmental Health
- Toxicology
- Neuroscience
Background:
- Chemical intolerance is linked to heightened trigeminal nerve sensitivity and inflammation.
- Previous theories suggest irritants initiate inflammatory processes in nasal mucosa.
Purpose of the Study:
- To investigate the intranasal inflammatory and irritative effects of ethyl benzene and methyl ethyl ketone (MEK) in chemically sensitive individuals.
- To compare inflammatory biomarker levels and subjective irritation ratings between sensitive subjects and controls.
Main Methods:
- 12 chemically sensitive subjects and 12 controls were exposed to varying concentrations of ethyl benzene and MEK.
- Nasal secretions were analyzed for inflammatory biomarkers: eosinophil cationic protein (ECP), myeloperoxidase (MPO), interleukin 1β (IL-1β), substance P (SP), and neurokinin A (NKA).
- Subjects self-reported nasal irritation severity before, during, and after exposure.
Main Results:
- No significant changes in inflammatory biomarker concentrations were observed in either group after exposure to the solvents.
- Subjective ratings of nasal irritation were higher in chemically sensitive individuals compared to controls, irrespective of the substance or concentration.
- No significant differences in reported irritations were found between exposure conditions.
Conclusions:
- The studied industrial solvents (ethyl benzene, MEK) may have a weaker capacity to induce intranasal irritative effects than previously hypothesized.
- While chemically sensitive individuals report more irritation, objective inflammatory markers do not support a strong physiological response to these specific chemicals at tested concentrations.
