Health effects of PM2.5 sources on children's allergic and respiratory symptoms in Fukuoka, Japan

Exposure to fine particulate matter (PM2.5) is a potential aggravating factor for respiratory and allergic diseases. However, which PM2.5 sources are associatedwith such diseases remains unclear. This study aimed to investigate the association of PM2.5 sources with allergic and respiratory symptoms in schoolchildren. PM2.5 samples were collected in Fukuoka during the spring in 2014 and 2015. Asian dust was observed in 2014. Ion components, elemental components, and organic components were analyzed. Positive matrix factorization (PMF) was conducted to calculate PM2.5 concentrations from each source. Mixed logistic regression analysis with a random intercept for each schoolchildwas performed to evaluate the association of components and sources with symptoms. Among 2317 schoolchildren, the mean prevalencewas 28.9%, 23.6%, 11.2%, and 11.4% for lower respiratory, nasal, ocular, and skin symptoms, respectively. PMF identified the following six PM2.5 sources Secondary sulfate and coal combustion, Secondary nitrate, Heavy oil combustion, Sea salt, Soil and Traffic emission. An interquartile range of PM2.5 mass was associated with nasal (Odds ratios 1.08, 95% confidence interval [1.03, 1.13]), ocular (1.10, [1.04, 1.16]), and skin symptoms (1.13, [1.06, 1.20]). Among the source factors, Heavy oil combustion was significantly associatedwith nasal symptom (1.11, [1.05, 1.18]) while Sea salt was associated with nasal (1.06, [1.02, 1.11]) and skin (1.073, [1.01, 1.14]) symptoms. We found Soil, which might be affected by Asian dust, was associatedwith ocular (1.07, [1.03, 1.10]) and skin (1.05, [1.01, 1.08]) symptoms. Further studies in other seasons or places are needed to clarify the influence of PM2.5 sources on children's health. (C) 2018 Elsevier B.V. All rights reserved.