Since the late last century, the government has taken many measures to reduce emissions of air pollutants. RIVM research shows that the number of deaths following days with elevated concentrations of these substances in the air decreased by about a quarter between 1995 and 2019. This is mainly because there is less particulate matter and nitrogen dioxide in the air. The concentration of ozone has slightly increased during this period. It remains important for health to ensure less air pollution.

The RIVM investigated whether the relationship between mortality and exposure to particulate matter, nitrogen dioxide, or ozone changed between 1995 and 2019. For this, the RIVM looked at mortality figures and the concentration of air pollution on the day of death or the day before. This comparison shows that fewer people died after days with elevated concentrations. This is mainly due to the decrease in concentrations of particulate matter and nitrogen dioxide. The end year for the analysis was chosen as 2019 to exclude possible effects of the coronavirus pandemic.

Attention Needed for Ozone

Unlike particulate matter and nitrogen dioxide, the concentration of ozone slightly increased between 1995 and 2019. As a result, ozone forms a more significant part of air pollution compared to the other two substances. This means ozone contributes more to mortality figures after days with higher concentrations. Therefore, it is important to better understand the acute health effects of high ozone exposure and how ozone exposure can be reduced.

Relationship Between Mortality and Individual Substances

This comparison also shows that the risk of dying after the same amount of particulate matter or ozone has not changed. This risk appears to have decreased for nitrogen dioxide. It is unclear why this is the case.

Better Warning Capabilities

In general, the elderly, young children, and people with chronic conditions are more sensitive to the harmful effects of air pollution. It is important to further investigate which people have a higher risk of dying after days with elevated concentrations of air pollution. They can then be better warned during temporarily poorer air quality.

This study only looked at mortality due to short-term exposure to air pollution, not other acute health effects. This research was conducted on behalf of the Ministry of Infrastructure and Water Management.