From Exposure to Equity: Understanding Air Quality Impacts on Environment and Human Health

In recent years, the discussion around air quality has shifted from a technical concern to a central theme in environmental and public health policy. What we once considered a background factor is now recognized as a key driver of disease patterns and population vulnerability.

Air quality is now widely recognized as a significant determinant of environmental and public health, capable of influencing the spread and prevalence of disease [1]. Global exposure models consistently attribute several million premature deaths to air pollution each year [2,3].

The WHO Air Quality Guidelines emphasize that adverse effects occur even at low concentrations of pollutants [4], while the Lancet Commission on Pollution and Health ranks air pollution as the leading environmental cause of premature death worldwide [5,6]. Regional assessments, including analyses by the Global Burden of Disease, reveal mixed trends: some countries show gradual improvements, while others experience persistent or worsening exposure due to rapid urbanization, demographic changes, or climate pressures [7,8].

The global picture, however, tells only part of the story. Behind the numbers lie institutional dynamics that shape how populations experience air pollution. Accordingly, previous work has shown that fragmented regulatory systems, peremptory ordinances, and delayed communications can amplify population exposure, as documented in studies on water quality governance that highlight the limitations of non-preventive approaches and the need for robust early warning mechanisms [9,10]. These governance challenges parallel those seen in air quality management, where limit exceedances, temporary exemptions, and poor enforcement can produce systematic disparities.

Equally important is how communities interpret and react to environmental threats. Scientific data alone is often not enough to guide behavior or trust. In fact, risk perception and public confidence influence responses to environmental threats [11,12,13]. Research on emotional epidemiology has shown how media amplification, outrage, and fluctuating public attention can influence compliance, institutional credibility, and health protection behaviors [14]. Similar dynamics are observed during air quality episodes, from dust storms to smog events, where perceived risk may diverge from measured exposure [15,16].

Yet, exposure does not end at the doorstep. The places where people live, work, and spend most of their time profoundly shape their health risks. Thus, indoor environments add an additional layer of complexity [17]. Housing conditions, ventilation, heating sources, and microbial contamination substantially alter exposure, reinforcing the need to consider the indoor-outdoor continuum in health assessments [18]. Adding to these dimensions are vulnerability and environmental justice, as communities living near industrial facilities or in disadvantaged areas often face higher levels of pollution and express lower levels of institutional trust [19].

Finally, climate change acts as a powerful risk multiplier. IPCC AR6 shows how heat waves, stagnation events, forest fires, and alterations in circulation patterns intensify the formation and distribution of pollutants [20,21], creating conditions in which environmental and social vulnerabilities converge.

In this complex landscape, the MDPI cross-journal section Topic “Impacts of Air Quality on Environment and Human Health” provides a multidisciplinary platform to examine how environmental pressures, exposure pathways, and health outcomes interact. Integrating atmospheric sciences, epidemiology, clinical research, building physics, and public health perspectives, the column promotes a comprehensive understanding of exposure and its consequences, an essential step toward policies that effectively reduce exposure disparities and protect those at greatest risk.

• Evidence Emerging from the Topic Issue “Impacts of Air Quality on Environment and Human Health”

The contributions included within the cross-journal Topic “Impacts of Air Quality on Environment and Human Health” (available online: https://www.mdpi.com/topics/6G59BQ84MG, accessed on 6 December 2025) reflect these complexities in tangible ways and collectively illustrate the multidimensional nature of exposure pathways and their health implications. Though heterogeneous in setting, population, and methodological approach, they converge on three central themes: vulnerability, environment–health interactions modulated by climate or built environments, and the need for integrated assessment frameworks capable of linking environmental signals to clinical outcomes.

The first contribution highlights the persistence of poor indoor air conditions where structural disadvantages, inadequate ventilation, and building characteristics intersect [22]. It is important to emphasize that targeted interventions have been able to reduce pollutant concentrations, demonstrating that improving indoor environments is a feasible and high-impact public health strategy. This work reinforces the concept, in line with the focus on indoor and outdoor air quality, that housing is a determining factor in environmental exposure, particularly for populations already burdened by socioeconomic vulnerability [15].

A second study examined how atmospheric processes can influence health outcomes through mechanisms that go beyond respiratory outcomes [23]. This contribution also highlights the need to examine non-traditional interactions between pollutants and health, especially in arid and semi-arid regions where dust is a dominant atmospheric component. Moreover, these findings also underscore the importance of considering non-respiratory exposure pathways: environmental contaminants present in other matrices—such as drinking water—have similarly been shown to exert genotoxic effects with relevant health implications [24].

The third study adds epidemiological depth by quantifying the relationship between environmental air pollutants and hospital admissions for diabetes [25]. Heating, temperature inversions, and complex emission sources illustrate how geographical and climatic specificities can amplify the impact of pollutants on health outcomes.

An additional atmospheric–health interaction is provided by the fourth published study, which evaluated the combined effect of non-optimal wet-bulb temperature and black carbon exposure on emergency visits for ischemic heart disease [26]. The results demonstrate that climatic stress and pollutant exposure do not operate independently: instead, temperature–pollution co-exposures can potentiate cardiovascular risk, underscoring the importance of integrating meteorology into short-term risk assessment.

Finally, a longitudinal clinical study explored the quality-of-life trajectories of patients with chronic wounds [27]. Although not directly focused on air pollution, the article contributes an essential perspective: populations with chronic health conditions often exhibit heightened vulnerability to environmental stressors.

Taken together, the five articles reveal a consistent narrative:

• Air quality risks are context-dependent and influenced by climate, geography, and the built environment;
• Vulnerability, whether socioeconomic or clinical, consistently amplifies the effects of exposure;
• Atmospheric processes can influence health outcomes far beyond respiratory endpoints;
• Significant improvements are possible when environmental and social determinants of exposure are addressed simultaneously.

These insights set the stage for identifying emerging cross-cutting issues that remain under-explored and will be central to designing the next generation of air quality and health research.

• Future Perspectives: Towards Integrated, Equitable, and Adaptive Air-Quality Science

What, then, does the future of air quality and health research require from us? The evidence emerging from this thematic issue, together with the consolidated results of global assessments [28,29,30,31,32,33,34,35], suggests a new generation of air quality and health research being focused on equity and climate sensitivity, responding to the need to explore the following topics:

• Evaluation of predictive models incorporating climate-pollution dynamics.
• Integration of vulnerability and equity into exposure epidemiology.
• Linking environmental determinants to clinical pathways.
• Evaluation of psychosocial and behavioral dimensions.
• Strengthening One Health and Planetary Health approaches.
• Moving toward protective environmental governance.

In conclusion, future research must align with scientific evidence to protect populations from increasing climate and environmental change.