Allergic diseases and asthma are on step increase in Portugal and in the western world. Currently more than 150 million Europeans suffer from these diseases and estimates suggest that by 2050 half of the European population will be affected. Urbanisation and related detrimental exposures – air pollution, heat stress, poor and unequal access to natural and biodiverse spaces – constitute possible culprits for such dramatic increase in allergic diseases and asthma.

EXALAR XXI is an innovative and multidisciplinary project that will involve geography, geographic information systems and technologies, medicine, biology, urban planning and environmental sciences to better understand the link between urban environment and allergic diseases and asthma. Aligned in the regional and national priority domains and societal challenges, EXALAR XXI has as overall objective to investigate the impact of exposure to urban pollution, green and blue spaces, and biodiversity, since conception to 10 years of age, on the development of allergic diseases and asthma in a population-based cohort from Porto Metropolitan Area, Geração XXI.

EXALAR XXI project will be grounded on detailed clinical, genetic and biological data longitudinally collected in a cohort of 8748 newborns that since birth have been regularly followed. Additionally, EXALAR 21 it will be also anchored on mixed data sources that will allow a deep characterization of the biogeophysical exposures (pollution, green and blue spaces and biodiversity) across Porto Metropolitan Area. The integration of clinical and environmental data will be possible since all participants from the cohort are georeferenced, thereby allowing matching participants to places and the tracking of cumulative and spatially varying environmental exposures.

The multidisciplinary nature of the project will naturally bring multifaceted outputs that will ultimately contribute to reduce the burden of allergy and asthma in Portugal and eventually in other settings. In one hand, EXALAR XXI will produce impacting and high-quality scientific publications, reports and communication. On the other, we aim at answering to real-life and practical problems; EXALAR XXI will result in urban planning recommendations and it will generate unique information about the biological and epigenetic mechanisms beyond the development of allergy and asthma. The first will be useful for territorial authorities and the second to the clinicians and health researchers.