Previous studies have explored relationships of air pollution and metabolic profiles with lung function. However, the metabolites linking air pollution and lung function and associated mechanisms have not been reviewed from a life-course perspective. Here we provide a narrative review summarizing recent evidence on the associations of metabolic profiles with both air pollution exposure and lung function in both children and adults. Twenty-six studies identified through a systematic PubMed search were included with 10 studies analyzing air pollution-related metabolic profiles, and 16 analyzing lung function-related metabolic profiles. A wide range of metabolites were identified being associated with short- and long-term exposure, partly overlapping with those linked to lung function in the general population
and respiratory diseases such as asthma and COPD. The existing studies show that metabolomics offers potential to identify biomarkers linked to both environmental exposures and respiratory outcomes, but many suffer from small sample size, cross-sectional designs, preponderance on adult lung function, heterogeneity in exposure assessment, lack of confounding control and omics integration. The ongoing EXposome Powered tools for
healthy living in urbAN Settings (EXPANSE) project aims at addressing some of these shortcomings by combining biospecimens from large European cohorts, and harmonized air pollution exposure and exposome data.