Since the end of the previous century, the government has ramped up the number of measures to reduce emissions of air pollutants. RIVM research has shown that the number of people who died after multiple days with elevated concentrations in the air of these pollutants dropped by around 25% between 1995 and 2019. This was mainly due to lower concentrations of airborne particulate matter and nitrogen dioxide. However, the same period saw a slightly higher concentration of ozone. To ensure people’s health, we need less air pollution.
RIVM has studied whether the relationship between mortality and exposure to particulate matter, nitrogen dioxide or ozone changed between 1995 and 2019. To this end, RIVM compared mortality figures with the concentration of air pollutants on the day a person died or on the day before. The comparison showed that fewer people died after multiple days with elevated concentrations than before. This was mainly due to a drop in concentrations of particulate matter and nitrogen dioxide. 2019 was picked as the final year of the analysis to exclude any influence of the COVID-19 pandemic.
Greater attention to ozone required
In contrast to particulate matter and nitrogen dioxide, the concentration of ozone slightly rose between 1995 and 2019. This is why ozone now constitutes a larger part or air pollution when compared to the other two. As a result, ozone is a higher contributing factor to mortality figures after multiple days with elevated concentrations. This is why it is key to collect more information on the acute health effects of high levels of ozone exposure and on how exposure to ozone can be reduced.
Relationship between mortality and individual substances
The comparison also revealed that the risk of death after being exposed to a similar quantity of particulate matter or ozone has not changed. For nitrogen dioxide, this risk seems to have gotten smaller. The reasons for this are unclear.
Enhanced warning capability
In general, the elderly, young children and people suffering from a chronic condition are more susceptible to the harmful effects of air pollution. Further research is needed to examine which people are at a greater risk of dying after multiple days of elevated concentrations of air pollutants. This will make it possible to send them more targeted warnings in case of temporarily poorer air quality.
This study only considered deaths due to short-term exposure to air pollution, not other acute health effects. It was commissioned by the Ministry of Infrastructure and Water Management.