Comparisons of lifetime exposures between differently polluted areas and years of life lost due to all-cause mortality attributable to air pollution

Background

Lifetime (or long-term) exposure to air pollution has been linked to an increased risk of premature death. This association might persist even at low air pollutant concentrations level. The objective was to describe and compare lifetime exposures to PM₁₀, PM_2.5, NO₂, benzene, and benzo(a)pyrene in two differently polluted localities and quantify years of life lost due to all-cause mortality attributable to PM₁₀, PM_2.5, NO₂.

Methods

The study population was selected from two differently polluted localities of the Czech Republic from the period 2000–2017. For determination of lifetime exposures specially developed methodology for historical air pollutants time series concentrations estimation was used. Estimated lifetime exposures, new WHO air quality guideline levels and relative risks were used to quantify years of life lost due to all-cause mortality attributable to air pollutants.

Results

Significant differences in lifetime exposures of air pollutants between study areas were found. Average lifetime exposure to PM₁₀, PM_2.5, NO₂, benzene and B(a)P was 45.6 μg/m³, 34.9 μg/m³, 18.1 μg/m³, 2.1 μg/m³and 2.6 ng/m³, respectively, in high-polluted area, against 24.9 μg/m³, 19.4 μg/m³, 13.3 μg/m³, 0.8 μg/m³, 0.4 ng/m³ in low-polluted area. All-cause mortality and years of life lost due to all-cause mortality (non-external) were higher in high-polluted area. The highest contribution was found for PM_2.5, when the population attributable fraction was at the 23% level for the high polluted area and at the 14% level for the low polluted area. The highest losses of 35,776 years per 100,000 men or 131 days per 1 man were achieved in the high polluted area and in a case of PM_2.5 exposure, namely for men in the age category of 80–84 years. Additionally, the results were expressed per number of deaths. The average value for the number of deaths attributable to PM_2.5 exposure was 4.75 years per1 death man, or 3.51 years per 1 death woman in a high-polluted area.

Conclusions

Expression of years of life lost due to all-cause mortality attributable to air pollution per number of deaths can be more appropriate for communication about health risks or in the field of public health protection.