Effects of Air-Pollution Control on Death Rates in Sweden: an Intervention Study

The Carbon Tax is one of the main climate change policies aimed to reduce the CO2 emissions. Policies aimed to contain CO2 emissions, by limiting the burning of fossil fuels, also decrease emissions of other greenhouse gases (GHGs), e.g. SO2, NO2, PM10 and SO4, avoiding changes in temperatures and damaging effects on human health.
Sweden has been one of the first countries in the world to introduce Carbon Taxes on the 1st January 1991 levied on oil, coal, natural gas, and liquefied petroleum gas, petrol and aviation fuel in domestic traffic. An evaluation study of the Swedish Carbon Tax carried out by the Swedish Environmental Protection Agency concludes that the CO2 tax ‘‘[…] has helped to reduce emissions of carbon dioxide in line with Swedish environmental policy’’.
The review of part of the existing literature on epidemiological studies confirms that pollution and increased mortality have been associated in many different parts of the world. Nevertheless, there is still a great uncertainty about the methodological reliability of these studies as few performed panel data analysis and/or investigated the role played by the environmental policy legislation.
The purpose of this study is to investigate whether a climate change mitigation policy, i.e. the carbon tax, has contributed to reduce the death rate through a reduction in the level of air pollutants in five Swedish counties over the period 1985-2000.
A monthly panel data set was used to analyse the effects of four pollutants (NO2, SO2, SO4, O3) on death rates caused by cardiovascular and respiratory problems by gender. Each model was adjusted for seasonality. Moreover, a structural change analysis estimated the efficacy of the Carbon Tax.
Most of the results obtained were consistent with the literature as NO2, SO2, SO4 and O3 were found to have a significant and adverse impact on human health. In particular, SO2 resulted to be responsible for both cardiovascular and respiratory deaths especially in the colder months when the concentration levels were at their highest.
Moreover, the implementation of the Carbon Tax was shown to have contributed to a reduction in death rates. In particular, reductions in SO2 resulted to have a significant impact in limiting the number of deaths for cardiovascular male disease. SO4 had the same effects on cardiovascular female and respiratory female mortality.