Research on the association between ambient PM2.5 and its components and psychological distress among Chinese children and adolescents aged 9-18 years

Abstract

Objective: To analyze the association between exposure to ambient PM2.5 and its components [sulfate (SO42-), nitrate (NO3-), ammonium (NH4+), organic matter (OM), and black carbon (BC)] and psychological distress among school children and adolescents aged 9 to 18 years in China. Methods: Based on data from the 2019 Chinese National Survey on Students' Constitution and Health, 130 808 children and adolescents aged 9 to 18 years were included. Scoring and determination of higher psychological distress were based on the Kessler Psychological Distress Scale (K10), and annual average exposure data for air pollution were matched by survey location and time. We used a restricted cubic spline approach based on logistic regression to fit the associations between PM2.5, SO42-, NO3-, NH4+, organic matter, black carbon concentrations, and psychological distress. Logistic regression models were used to analyse different age, gender, BMI and physical activity subgroups to estimate the association between exposure to high levels of pollution and high levels of psychological distress in different subgroups. Results: The proportion of children and adolescents with high levels of psychological distress in China was 30.4%, with girls being higher than boys at 31.6% and 29.1%, respectively (P<0.05). A non-linear positive association existed between exposure to PM2.5, SO42-, NO3- and organic matter concentrations and higher psychological distress. As PM2.5, NO3-, NH4+, organic matter, and black carbon concentrations continued to rise, the increase in the risk of higher psychological distress slowed, while SO42- showed little change in the OR of psychological distress at lower concentrations but continued to rise at higher concentrations. PM2.5 and its components were statistically associated with psychological distress in the physically inactive group but not in the physically active group. The association between high levels of pollutants and high psychological distress was stronger among students aged 9 to 12 years compared with students aged 13 to 15 years and 16 to 18 years. Conclusions: The ambient pollutant PM2.5 and its components are associated with psychological distress in children and adolescents aged 9 to 18 years in China. High pollutant exposure is a risk factor for high psychological distress among physically inactive children and adolescents, and there are age differences in the association between PM2.5 and components and psychological distress.