Air pollution as an early determinant of COPD

Abstract

COPD is a progressive and debilitating disease often diagnosed after 50 years of age, but more recent evidence suggests that its onset could originate very early on in life. In this context, exposure to air pollution appears to be a potential contributor. Although the potential role of air pollution as an early determinant of COPD is emerging, knowledge gaps still remain, including an accurate qualification of air pollutants (number of pollutants quantified and exact composition) or the "one exposure-one disease" concept, which might limit the current understanding. To fill these gaps, improvements in the field are needed, such as the use of atmosphere simulation chambers able to realistically reproduce the complexity of air pollution, consideration of the exposome, as well as improving exchanges between paediatricians and adult lung specialists to take advantage of reciprocal expertise. This review should lead to a better understanding of the current knowledge on air pollution as an early determinant of COPD, as well as identify the existing knowledge gaps and opportunities to fill them. Hopefully, this will lead to better prevention strategies to scale down the development of COPD in future generations.

FIGURE 1

Early determinants of altered lung function trajectories and associated risk. BPD: bronchopulmonary dysplasia.

FIGURE 2

A schematic view of the atmospheric simulation, starting to the left with a continuous introduction of air and precursors in the atmospheric simulation chamber, then under the irradiation of Xe lamps at the top of the chamber the chemistry takes place, leading after a few hours to a secondary atmosphere “feeding” the exposure device where the exposed pre-clinical models are positioned, while the reference pre-clinical samples are exposed to a reference atmosphere (air filtered from pollutants). Analytical instruments allow to qualify/quantify the pollutants present in the simulated atmosphere, both online and offline (PolluRisk platform, France). ACSM-ToF: time-of-flight aerosol chemical speciation monitor; CESAM: multiphase atmospheric experimental simulation chamber; CPC: condensation particle counter; FTIR: Fourier-transform infrared spectroscopy; GC-FID: gas chromatography–flame ionisation detection; PTR-MS-ToF: proton transfer reaction time of flight mass spectrometry; SFE-GC-MS: supercritical fluid extraction with gas chromatography–mass spectrometry; SMPS: scanning mobility particle sizer; UPLC-MS-QToF: ultra-performance liquid chromatography quadrupole time of flight mass spectrometry; VOC: volatile organic compound.

FIGURE 3

SWOT (strengths, weaknesses, opportunities and threats) analysis of the current knowledge of air pollution as an early determinant of COPD. PM: particulate matter; PM_0.1: PM equal or inferior to 0.1 µm in diameter.