Risk communication of ambient air pollution in the WHO European Region: review of air quality indexes and lessons learned
This report provides an overview of air quality indexes used in 37 Member States of the WHO European Region and some observations/suggestions for future developments to improve risk communication on air pollution. In the Region, air quality information is widely available to the public, both online and through official mobile apps. Forecasted air pollution information is often reported alongside near real-time air pollution monitoring data. Most countries use a national Air Quality Index instead of a uniform index, such as that provided by the European Environment Agency, and some use several different indexes. A wide range of approaches are used to calculate index values, but the general structure of indexes is similar. Many indexes lack rigorous validation to ensure that index values correspond to population-level health risks. Quality of the accompanying health messaging varies widely, but good examples were found throughout the Region. The best examples provide information on the affected subpopulations, describe likely symptoms and make specific recommendations to reduce exposures and health risks. Given the wide range of pollutant concentrations, mixtures and risk preferences observed, it is critical to provide tailored health messaging to accompany index levels. In addition to health-based validation studies, research should focus on understanding how the public uses air quality indexes (including special alerts): how many people are aware of the index, whether they consult it regularly, whether they modify behaviour in response to the information, and what specific actions they take in response to index values and associated health messages.