The World Health Organization (WHO) Regional Office for Europe has published a critical new document, Health risks of air pollution in Europe: HRAPIE-2 project, providing updated, evidence-based guidance that is set to become a vital resource for policymakers and organizations worldwide, including the Global Open Air Quality Standards (GO AQS). This report updates the original 2013 HRAPIE guidance and is a key tool for quantifying the immense health burden of air pollution.

New Science for Health Risk Assessment (HRA)

The core of the HRAPIE-2 document is the provision of up-to-date Concentration-Response Functions (CRFs), which are statistical models used in Health Risk Assessments (HRAs) to estimate the relative risk to a population for a given change in air pollutant concentration. By quantifying these effects, the guidance informs evidence-based clean air policies and climate change mitigation strategies.

The report is built upon comprehensive systematic reviews and evidence syntheses, enabling a more thorough assessment of effects from different exposure durations. The guidance covers three key pollutants:

• Particulate Matter (PM), including PM2.5​.
• Ozone (O3​).
• Nitrogen Dioxide (NO2​).

Crucially, the guidance has expanded to include a larger number of mortality and morbidity outcomes, allowing for more comprehensive health assessments. This includes data relevant to long-term exposure to PM2.5​ and NO2​, and short-term exposure to PM2.5​, NO2​, and O3​. The report also features a section on Economic Assessment to better communicate the benefits of clean air policies.

Impact on GO AQS

Although primarily intended for the WHO European Region, the evidence base and suggestions within HRAPIE-2 are considered broadly relevant to other WHO regions. This makes the new guidance invaluable for global initiatives, such as the GO AQS.

As GO AQS develops its authoritative guidelines for scientists, policymakers, and industry, the updated CRFs from the HRAPIE-2 project will be a fundamental tool. By incorporating the latest CRFs, GO AQS and national policy bodies committed to improving air quality, as called for by the Budapest Declaration on Environment and Health, can ensure their standards are based on the most robust, up-to-date scientific understanding of health risks.

This synergy between the WHO’s technical guidance and GO AQS’s standardization efforts marks a major step forward in creating a world where everyone can breathe clean air.