The effect of PM2.5 exposure and risk perception on the mental stress of Nanjing citizens in China.

The multidimensional characteristics and temporal dynamics of environmental risks have stimulated a social-scientific approach towards air pollution issues in recent decades. It's now widely acknowledged that air pollution has an ineligible influence on the psychological wellbeing of citizens beyond its well-established physical impact. We explored how fine particulate matter (PM2.5), an essential air pollutant associated with morbidity and mortality, interacted with aspects of risk perception to influence citizen's mental stress level. Questionnaire data from 508 Nanjing citizens in China were collected across four seasons within an 18-month period. We found no evidence that mental stress was directly influenced by real-time PM2.5 exposure. However, path analysis revealed that mental stress was subjected to the indirect influence of physical symptoms (β = 0.076, p = 0.11), by increasing perceived effect on health and increasing attribution to indoor pollution sources (β = 0.038, p = 0.005). Indoor attribution of PM2.5 pollution was associated with perceived familiarity with risk (β = -0.095, p = 0.033), whereas outdoor attribution was associated with perceived control of risk (β = 0.091, p = 0.041). Public risk acceptable rate (PRAR) decreased as PM2.5 concentration increased. In females, but not males, greater trust for government was associated with the increased acceptance of PM2.5 (Year2017: β = -0.19, p = 0.003; Year2022: β = -0.21, p < 0.001). Using psychological statistical methods, our study implied that air pollution has a substantial association with psychological wellbeing in various ways, which might provide some references for public healthcare and risk communication.