ACT-AQ – ACTing to improve Air Quality
© Helmholtz Forum Earth and Environment
Air pollution is one of the greatest environment-related health risks worldwide. Current research is particularly focused on ultrafine particles (UFP), ozone (O₃), and fine particulate matter (PM2.5), as they are associated with significant impacts on health, climate, and the environment. The revised EU Air Quality Directive (AAQD), which has been in effect since December 2024, introduces stricter limit values, expanded monitoring requirements, and the mandatory use of air quality models. Germany must transpose these requirements into national law by the end of 2026 and fully implement them by 2030.
The ACT-AQ project brings together expertise from five Helmholtz Centers as well as partners from the Leibniz and Max Planck sectors in the fields of atmospheric research, climate science, epidemiology, and neuroscience. The goal is to synthesize existing knowledge, close key knowledge gaps, and strengthen the scientific basis for assessing air pollutants under current and future climate conditions—particularly with regard to the combination of air pollution and heat.
A particular focus is on supporting the implementation of the EU Air Quality Directive in Germany. This includes establishing a monitoring system for ultrafine particles, improving the use and interpretation of air quality models, and developing practical scientific foundations for government agencies and policymakers.
Participating Helmholtz Centers
Helmholtz Center Hereon, Forschungszentrum Jülich (FZJ), Karlsruhe Institute of Technology (KIT), Research Institute for Sustainability at GFZ (RIFS), Helmholtz Munich
Other participating institutions: Leibniz Institute for Environmental Medicine (IUF), Max Planck Institute for Human Development (MPI-B)
Principal Investigators
Dr. Volker Matthias (Hereon), Dr. Martin Ramacher (Hereon), Dr. Peter Hoffmann (GERICS/Hereon), Bettina Steuri (GERICS/Hereon), Prof. Dr. Erika von Schneidemesser (GFZ/RIFS), Prof. Dr. Tim Butler (GFZ/RIFS), Prof. Dr. Anke Nölscher (FZJ), Dr. Robert Wegener (FZJ), Dr. Anne Caroline Lange (FZJ), Dr. Gholamali Hoshyaripour (KIT), Dr. Harald Saathoff (KIT)
© Helmholtz Forum Earth and Environment
Kick-Off
On July 8 and 9, 2026, the ACT-AQ project of the Helmholtz Forum Earth and Environment held its kick-off workshop in Hamburg to bring the consortium together and identify common priorities for the project’s future work. In addition to substantive work on the planned synthesis publications on ozone and ultrafine particles, keynote speeches from policymakers and government officials placed the project within the current context of the European Air Quality Directive.
The workshop report can be found here.
Contact
Dr. Volker Matthias (Hereon): volker.matthias@hereon.de
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