Urinary Polycyclic Aromatic Hydrocarbon Metabolites and Altered Lung Function in Wuhan, China

Rationale: Exposure to polycyclic aromatic hydrocarbons (PAHs) has been associated with adverse effects on the respiratory system. However, the association between internal levels of PAH metabolites and lung function levels remains unclear.

Objectives: We investigated the relationships between urinary PAH metabolite concentrations and lung function levels in a general Chinese population.

Methods: Lung function and 12 urinary PAH metabolites were measured in 2,747 participants from the Wuhan-Zhuhai cohort in China. Associations between urinary PAH metabolites and lung function were analyzed by linear mixed models. We also investigated associations among urinary PAH metabolite concentrations, traffic exposure time, and dietary PAH exposure.

Measurements and main results: We found significant associations between increased levels of urinary PAH metabolites and reduced lung function. Each 1-U increase in log-transformed levels of 2-hydroxynaphthalene, 9-hydroxyfluorene, 2-hydroxyfluorene, 4-hydroxyphenanthrene, 9-hydroxyphenanthrene, 3-hydroxyphenanthrene, 1-hydroxyphenanthrene, 2-hydroxyphenanthrene, 1-hydroxypyrene, or total urinary PAH metabolites was associated with a 23.79-, 19.36-, 41.76-, 36.87-, 33.47-, 27.37-, 39.53-, 34.35-, 25.03-, or 37.13-ml reduction in FEV1, respectively (all P < 0.05). Each 1-U increase in 2-hydroxynaphthalene, 2-hydroxyfluorene, 4-hydroxyphenanthrene, 1-hydroxyphenanthrene, 2-hydroxyphenanthrene, or total urinary PAH metabolites was associated with a 24.39-, 33.90-, 27.15-, 28.56-, 27.46-, or 27.99-ml reduction in FVC, respectively (all P < 0.05). The total urinary PAH metabolites concentration was positively associated with both traffic exposure time and dietary PAH exposure among nonsmokers.

Conclusions: Total and specific urinary PAH metabolites were associated with lung function reduction in a general Chinese population. Further studies are needed to investigate the potential mechanism by which PAHs induces lung function reduction.