Revista de diagnóstico y biomarcadores moleculares

Quantitative Analysis of VOCs in Exhaled Breath from Asian Volunteers: A Pilot Study

Abstract

Shruti Pavagadhi and Rajasekhar Balasubramanian

Background: High incidences of respiratory ailments have been long attributed to rapid industrialization and fast economic growth in developing nations within Asia. Urbanization in particular has led to a significant increase in outdoor and indoor air pollution in Asian countries, affecting lung health for different population groups. Air pollutants enter the human systems via the inhalation pathway, and their measurement in exhaled breath has been suggested as a non-invasive alternative for early diagnosis of asthma and lung cancer. Routine monitoring of selected volatile organic compounds (VOCs) in breath often requires the use of robust analytical techniques with standardized sample collection procedures for reliable risk assessment. Currently, such analytical data are relatively sparse in the literature for Asian population groups due to lack of quantitative analysis of VOCs in exhaled breath. To fill the knowledge gap, a present pilot study was initiated to evaluate the suitability of an in situ instrumental technique for breath measurements among a small group of diverse Asian volunteers.

Methods: The study was conducted to explore the use of PTR-MS (Proton Transfer Reaction- Mass Spectrometry) with BET (Buffered End Tidal) breath sampling for real-time measurements of selected VOCs in healthy Asian volunteers (35 healthy subjects from different ethnic groups). Breath samples were analyzed for eight VOCs (well-known biomarkers) using BET-PTRMS, namely, acetone, isoprene, ethanol, acetaldehyde, acetonitrile, acrolein, benzene and toluene. The eight VOCs were confirmed independently using a complementary analytical technique (SPME-GCMS (Solid Phase Micro-Extraction-Gas Chromatography Mass Spectrometry)).

Results: Acetone (58% abundance) was found to be the predominant VOC, followed by isoprene (27%) and acetaldehyde (9%) in the breath samples of 35 healthy Asian healthy volunteers from diverse ethnic groups. Results obtained from the present study have been compared to those available in literature for different population groups.

Conclusion: Overall, BET-PTRMS is a promising real-time monitoring tool for measurements of suitable VOCs that can be used as breath signatures (“smell prints”) in Asian population groups as it demonstrated a high sensitivity and versatility required for successful practical applications. Further in-depth investigations with more number of subjects under clinical and sub-clinical settings are warranted to evaluate the potential of using BETPTRMS as a routine early diagnostic tool for Asian population groups at-risk of developing COPD, lung cancer or serious respiratory illnesses.