European Code Against Cancer, 5th edition - outdoor and indoor air pollution and cancer.

Most European Union (EU) residents live in areas where outdoor air pollution levels exceed the 2021 World Health Organization (WHO) air quality guidelines for fine particles and nitrogen dioxide. Outdoor air pollution is classified as carcinogenic to humans, and both outdoor and indoor air contain established human carcinogens, including diesel exhaust particulates, benzo(a)pyrene [B(A)P] and benzene. The European Code Against Cancer, 5th edition (ECAC5), incorporates recommendations for individuals and policymakers aimed at reducing the cancer burden from both outdoor and indoor air pollution. A critical step is aligning EU air quality limit values with the more stringent 2021 WHO guidelines. This should be complemented by integrated policy measures, including stricter regulation of combustion emissions, promotion of active and environmentally friendly transportation, incentives for cleaner energy sources for heating and cooking, and harmonization with broader EU climate initiatives. At the individual level, emissions and exposure may be reduced by limiting car use, avoiding second-hand smoke, and refraining from burning wood or coal indoors or outdoors. Further exposure reduction may be achieved by limiting walking or cycling along heavily trafficked routes.