Air pollution is considered the greatest environmental risk to human health, according to international organisations such as the World Health Organization, the United Nations Human Rights Council and the European Environment Agency. A scientific review conducted by the University of Aveiro (UA) analysed how the concepts of inequality and environmental justice have been considered in the assessment of the health impacts of air pollution.
The study was authored by Alexandra Monteiro, Vera Rodrigues, Cecília Cardoso, Myriam Lopes, Peter Roebeling, Hélder Relvas, Pedro Seixas, Carla Gama and Ana Isabel Miranda, researchers from CESAM/DAO; Elisabete Figueiredo, from the Governance, Competitiveness and Public Policies Research Unit (GOVCOPP); and Sónia Gouveia, Adriano Gomes and Ana Martins, from the Institute of Electronics and Informatics Engineering of Aveiro (IEETA). All authors are participants in the ALICE research project, within which this work was developed. Following the project, the 1st National Conference on Environmental Justice was also organised.
In total, 99 scientific articles were analysed, considering different aspects such as the conceptual framework, the studied region, the temporal scale, the data and indicators used, and the analytical methods applied — statistical, numerical or survey-based.
The results show that studies on environmental justice associated with air pollution were conducted across 21 countries, with the United States accounting for the majority of the research (53%). Canada (6%) and China (5%) followed.
In temporal terms, more than half of the studies were published within the last five years, reflecting growing scientific interest in this topic. Most investigations focus on the long-term impacts of air pollution.
Regarding the data used, most studies focused on fine particulate matter (PM2.5), one of the pollutants most associated with health risks. However, only about half of the studies explicitly included health or exposure data.
All analysed articles addressed environmental justice issues related to socioeconomic status or race/ethnicity. Among the most frequently used socioeconomic indicators were income data (99%), followed by population and housing characterisation indicators.
The most common analytical approach was statistical analysis, used in 71% of the studies. Around 14% relied on surveys, while 15% used simulation models to explore scenarios.
According to the review, there is still room for the development of further studies, particularly in Europe and other underrepresented regions. The researchers advocate the use of more robust statistical models and mixed methods capable of dealing with the complexity of the multiple variables involved in this type of research.
At smaller geographical scales, the authors also recommend survey-based studies that integrate both individual and contextual socioeconomic indicators. The review further highlights that few studies address social perceptions or citizen engagement regarding air pollution issues.
The findings therefore point to the need for a deeper understanding of the social dimensions of air pollution, contributing to more equitable environmental and public health policies.
Original news published in: UA Notícias, 5 May 2026