The effects of particulate matter on perceived stress / depression and understanding of stress inequality in Seoul, South Korea

Described as the single greatest environmental health risk’, air pollution shortens our life expectancy by 20 months. Among the air pollutants, nothing is more harmful to our body than fine dust. However, this is not enough to reveal all of the fine dust (PM). A survey of Statistics Korea in 2018 displayed that the rate of the Koreans complaining ‘stress’ caused by PM constituted 82.5%, as a result of a steady increase from 77.9% in 2014. According to a public survey conducted by a media in 2019, 8 out of 10 respondents in their 20s and 30s exhibited that they have ever desired to emigrate due to fine dust. In light of this physical and emotional gravity of fine dust, this study sought to explain the effects of fine dust on the formation of negative affectivity such as stress and depression of Seoulites from 2015 to 2018. It also entails the other assumptions that fine dust could play a role in generating a more vulnerable class to negative affectivity (called ‘stress inequality’ in this study) and incurring additional social costs. In order that the research questions can be answered, both of a secondary quantitative and a primary qualitative analysis were utilized. Stated briefly as to findings, PM2.5 and PM10 increase stress and depression et al. of Seoullites during the given period. The index of stress rose by 0.0044 points for each 1 ‘g/m3 increase of PM2.5 and depression et al. increased by 0.006 points. Whereas PM10 did not exhibit a causal relationship with stress within the significance level, it augmented depression et al. by 0.005 points. PM2.5 was more influential on negative affectivity than PM10. In greater detail, stress was more eased in line with the increase of one unit of age - local tax - happiness with financial status - medical cost. In contrast, it was increased by order (of beta): crime rate - PM2.5 - traffic accident rate. Stress inequality is more related to labour conditions than to economic or education levels. Of extraordinary note is that there is a larger increase in stress caused by PM2.5 in a group which is not active in social participation such as voting than in the other group. Fine dust is undermining social trust, too. As the concentration level of PM2.5 increased, trust in the public sector decreased by 0.012 points. Among the experts on fine dust, over 9 out of 10 respondents (91.7%) agreed that negative affect led by fine dust can have repercussions on the whole Korean society. It implies that fine dust impairs not only the physical, psychological health of individuals but also the health of society. These findings suggest that it is time for the government to take serious consideration of the necessity to move toward a comprehensive policy including an approach to individual stress matters exacerbated by fine dust, beyond focusing on direct measures to reduce PM. Keywords: Stress, Depression, Fine dust, Particulate matter, Stress inequality, Social cohesion, Seoul