The interaction effects between exposure to ambient PM_2.5 and economic development on the settlement intention for...

Limited studies examined the interaction effects between exposure to ambient PM_2.5 and economic development on the settlement intention of floating population. We used binary logistic model to examine the association of PM_2.5, per capita GDP (PGDP), PM_2.5 [Formula: see text] PGDP on the settlement intention. Additive interaction term of PM_2.5 and PGDP level was used to investigate their interactive effects. Overall, each one grade increment in annual average PM_2.5 was associated with decreased probability of settlement intention (OR = 0.847, 95%CI: 0.811-0.885). The interaction effect between PM_2.5 and PGDP on settlement intention was significant (OR = 1.168, 95%CI: 1.142-1.194). The stratified analysis showed PM_2.5 exhibits lower settlement intention in the aged 55 years or above, engaged in low-skilled works, and living in the western China. This study indicates that PM_2.5-exposed will decrease the settlement intention of floating population. High economic development level can weaken the relationship between PM_2.5 and settlement intention. Policymakers should balance the socio-economic development and environmental health and focus on vulnerable population.