The Effects of Asian Dust for Allergic Symptoms may be Partly Attributed to PAH-Quinone, Secondarily Formed on the Dust Surface – Observational Study in 3 Regions in Japan

Abstract

Background/Aim: We showed that Asian dust (AD) exposure is associated with increased risk for exacerbations of asthma and allergic symptoms in children or pregnant women in Japan. AD particles contain anthropogenic pollutants such as PAHs. Further, its catalytic effects promote secondary-formation of chemicals, one of which, PAH-quinone is known to generate ROS in human body, which may contribute to allergic diseases. We estimated how much of the effects of AD are attributed to PAH-quinone. Methods: We conducted an observational study for 3,327 pregnant women during spring and fall in 2011-2013 in 3 regions in Japan as an adjunct study of Japan Environment and Children's Study. There, we timely acquired subjects’ daily allergic-symptoms by sending web-based questionnaires on some days for each participant. We also sampled TSP every day, and measured some PAH-quinones by HPLC. We estimated odds ratio (OR) of log-transformed AD per 1SD-change for occurrence of allergic symptom with interaction term of AD and PAH-quinone in the GEE logistic regression model. Results: Both AD and PAH-quinone showed significant associations with allergic symptom. Interaction term of AD and PAH-quinone was significantly larger than 0 (p<.01), and the OR of AD (per log-transformed 1SD change) when log-transformed PAH-quinone is mean, was 1.12 (95%CI: 1.04-1.22), while the OR was 1.34 when log-transformed PAH-quinone is 1SD above the mean. Conclusions: The effect of AD was significantly exacerbated by the presence of PAH-quinone. We may be able to reduce the effects of AD by reducing PAH emissions.