Impacts of low socioeconomic status and polycyclic aromatic hydrocarbons exposure on lung function among a community-based Chinese population.

Lung function is related to socioeconomic status (SES) and exposure to polycyclic aromatic hydrocarbons (PAHs). However, joint effect of SES and exposure to PAHs on lung function has been largely unknown. We aimed to investigate joint effects of SES and urinary OH-PAHs levels on lung function parameters. This study included 2739 Wuhan participants from the baseline survey of the Wuhan-Zhuhai (WHZH) Cohort Study (n=3053). They completed the questionnaire, physical examination and provided blood and urine samples. Twelve urinary monohydroxy-PAHs metabolites (OH-PAHs) and lung function were measured by gas chromatography-mass spectrometry and digital spirometers, respectively. Individuals with low educational levels and low or high levels of urinary ΣOH-PAHs had a 3.5% (95% CI: -5.4, -1.6%) or 4.2% (95% CI: -6.1, -2.3%) reduction in the ratio of forced expiratory volume in 1s to forced vital capacity (FEV1/FVC), respectively, and those with middle levels of education and high levels of urinary ΣOH-PAHs had a 2.1% (95% CI: -5.4, -1.6%) reduction in the FEV1/FVC ratio, rather than those with high levels of education and low levels of urinary ΣOH-PAHs. Individuals with low levels of education had a -3.0% (95% CI: -4.4, -1.6%) reduction in FEV1/FVC compared with individuals with high levels of education. Urinary OH-PAHs levels were marginally negatively related to FEV1 in all participants (p=0.073). The results indicated that there was a prominent effect of low levels of education and higher exposure to PAHs on lung function decline, indicating that it is a necessary to take measures to promote the education level and reduce exposure to environmental PAHs.