Introduction: One of the main concerns of governments in recent years has been the increase in per capita health expenditures, which is affected by several factors. The increase in gross domestic product (GDP), air pollution index and carbon dioxide (CO₂) emissions have had direct and indirect effects on health expenditure per capita. An increase in GDP can improve life, but an increase in air pollution and CO₂ emissions caused by human production activities usually causes health problems such as respiratory diseases, cardiovascular diseases, and climate changes. Health problems can increase the per capita health expenditure of people. In addition, these costs have negative effects on the economic productivity of society. Therefore, in this research, the relationship between air pollution and gross domestic product with health expenditures in the big cities of Iran including Tehran, Shiraz, Mashhad, Tabriz, Isfahan and Ahvaz is investigated. Considering that household income and air pollution are among the factors affecting household health expenses, therefore, investigating the relationship between these variables can be effective in finding solutions to improve the health level of the society and solve economic problems caused by the increase in health expenses.
Materials and Methods: In this study, the panel data model was used to investigate the factors affecting the per capita health expenditure in 5 major cities of the country. The investigated time period is between 2011-2022. To avoid fitting a false regression, the reliability of the variables is checked. To do this, Levin and Lane test is used. To test the co-accumulation of variables in the long term, Pedroni cointegration test was used, and to determine whether the model is a panel, Limer's F-test was used. Then, to determine whether the model is a model with fixed effects or a model with random effects, the Hausman test is performed. GMM method is used to estimate the model.
Results: The results of the model indicate that the increase in gross domestic product (GDP), air pollution index and carbon dioxide (CO₂) emissions had a positive and significant effect on the increase in per capita health expenditures. In this way, air pollution caused by the economic growth of cities causes an increase in disease and an increase in the cost of health care. As a result, the continuation of air pollution and provision of health expenses by the government causes a larger part of the government's budget to be allocated to the provision of health expenses.
Discussion: One of the most important goals of economic development is to achieve higher economic growth. It is expected that the health level of the society will improve as the GDP level increases. But the studies confirm that with the increase in the gross domestic product of each of Iran's big cities, the amount of air pollution has also increased, which has endangered people's health and caused an increase in health costs and an increase in the number of deaths. Therefore, in order to control the per capita health care costs in big cities, it is suggested to the authorities to consider using new and green technology, investing in public transportation and improving energy efficiency as well as preserving the environment in their plans. Also, imposing a tax on CO₂ emissions and encouraging the use of clean and green energy can be an economic stimulus to change unsustainable environmental behaviors.