Mortality and emergency hospitalizations associated with atmospheric particulate matter episodes across the UK in spring 2014

- In March-April 2014, local and regional PM2.5 air pollution built up over the UK
- PM2.5 during episode days was associated with ~ 600 deaths brought forward in total
- Emergency hospitalizations from exposure to PM2.5 during the episodes were ~ 1500
- Short-term health impact of PM2.5 was 2.0 to 2.7 times that of average spring levels
- Planning for health impacts of PM2.5 episodes may help manage healthcare resources

Exposure to particulate air pollution is known to have negative impacts on human health. Long-term exposure to anthropogenic particulate matter is associated with the equivalent of around 29,000 deaths a year in the UK. However, short-lived air pollution episodes on the order of a few days are also associated with increased daily mortality and emergency hospital admissions for respiratory and cardiovascular conditions. The UK experienced widespread high levels of particulate air pollution in March-April 2014; observations of hourly mean PM2.5 concentrations reached up to 83 μg m− 3 at urban background sites. We performed an exposure and health impact assessment of the spring air pollution, focusing on two episodes with the highest concentrations of PM2.5 (12-14 March and 28 March-3 April 2014). Across these two episodes of elevated air pollution, totalling 10 days, around 600 deaths were brought forward from short-term exposure to PM2.5, representing 3.9% of total all-cause (excluding external) mortality during these days. Using observed levels of PM2.5 from other years, we estimate that this is 2.0 to 2.7 times the mortality burden associated with typical urban background levels of PM2.5 at this time of year. Our results highlight the potential public health impacts and may aid planning for health care resources when such an episode is forecast.