Air pollution and life expectancy in the USA: Do medical innovation, health expenditure, and economic complexity matter?

Regardless of a country's income level, air pollution poses a significant environmental threat to human health. Long-term exposure to air pollution often triggers cardiovascular and respiratory diseases. Thus, air pollution significantly reduces life expectancy worldwide. The USA is one of the world's largest polluters of CO emissions, often used to represent air pollution. In this context, the main objective of this study is to examine the relationship between air pollution and life expectancy in the USA. In doing so, we control for the role of medical innovation, health expenditures, economic complexity, and government effectiveness using data for the period 1995-2019. The results indicate the existence of a cointegration relationship in the proposed model. The long-run coefficients are statistically positive for medical innovation and negative for CO emissions, economic complexity, and government effectiveness. On the other hand, health expenditures are ineffective in terms of life expectancy. Accordingly, medical innovation raises life expectancy, whereas CO emissions, economic complexity, and government effectiveness decrease it. Higher economic prosperity and health expenditures are not always beneficial to life expectancy. Therefore, policymakers need to take action to reduce air pollution and increase the comprehensiveness of economic prosperity benefits and health expenditure efficiency.