Exposure to polycyclic aromatic hydrocarbons (PAHs) in outdoor air and respiratory health, inflammation and oxidative stress biomarkers: A panel study in healthy young adults

Abstract

Exposure to polycyclic aromatic hydrocarbons (PAHs) can be associated with different types of health effects. However, the systemic changes of health effects between fluctuations of PAHs exposure have not been established. In this study, urinary hydroxylated PAHs (OH-PAHs) and 12 biomarkers were determined among 36 students from the urban to the suburb in Taiyuan in 2019. The concentration of Σ₁₂OH-PAHs in urban areas (28.2 and 21.4 μg/g Cr) was significantly higher than that in suburban area (16.8 μg/g Cr). The regression showed that hydroxy-phenanthrene (OH-Phe, 1/2/3/4/9-OH-Phe) was significantly positively correlated with lung function (PEF₂₅ and PEF₅₀), 8-hydroxydeoxyguanosine (8-OHdG), interleukin-8 (IL-8), and fractional exhaled nitric oxide (FeNO). Moreover, there were negative associations of 2-hydroxyfluorene (2-OH-Flu) with FVC and FEV₁. 1 unit increase of 1-hydroxypyrene (1-OH-Pyr) was negatively associated with 18.8% FVC, 17.3% FEV₁, and 26.4% PEF₂₅ in the suburban location, respectively. During urban₂, each unit change of 2-OH-Flu was associated with 10.9% FVC and 10.5% FEV₁ decrease, which were higher than those in suburban location. 8-OHdG decreased by 32.0% with each unit increase in 3-hydroxyfluorene (3-OH-Flu) during urban₂ (p < 0.05), while 1.9% in the suburban location. During the suburban period, the increase in OH-Phe was correlated with the decrease in malondialdehyde (MDA). The respiratory damage caused by PAHs in the urban disappeared after backing to the urban from the suburban area. Notably, despite the total significant liner mixed regression association of FeNO with multiple OH-PAHs, the association of FeNO with OH-PAHs was not significant during different periods except for 2-OH-Flu. Our findings suggested that short-term exposure to different concentrations of PAHs might cause changes in health effects and called for further research to investigate possible alterations between health effects and PAH exposure.

Keywords: FeNO; Inflammation; Lung function; OH-PAHs; Oxidative stress.