The interaction effects between exposure to ambient PM and economic development on the settlement intention for floating population in China.

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