Health impact of indoor air quality: biological, physical and economic considerations

Abstract

Background: Indoor air quality (IAQ) matters a lot more than people often realize and yet, it is still underappreciated, for human health. Long term exposure to indoor biological contaminants (like mold, allergens, microbial pollutants) plus chemical agents, especially inside places that are not ventilated enough, can lead to a range of problems-respiratory issues, cardiovascular effects, and even neurological complications. People spend plenty of time indoors, but the way biological factors, physical conditions, and socioeconomic context work together to shape IAQ still feels kind of disconnected in much of the existing research. Objective: To combine multidisciplinary evidence looking at how biological contaminants, ventilation parameters, and the economics surrounding residential air quality interventions all jointly affect health outcomes for occupants. Methods: We carried out a structured review of the available literature, using material from epidemiology, environmental engineering, and health economics. Studies were chosen based on how relevant they were to indoor biological pollutants, the performance of HVAC and ventilation systems, plus any cost-benefit work tied to IAQ upgrades. We also pulled together methodological ideas from biology, physics, and home economics, and tried to merge them into one broader analytical model. Results: Overall, the evidence suggests that mold growth and particulate pollutants are strongly linked with higher rates of asthma, allergic rhinitis, and long-lasting respiratory disease. When ventilation is adequate, the concentrations of biological contaminants drop in a meaningful way. Meanwhile, economic studies report that focused IAQ investments can produce measurable decreases in healthcare spending and productivity loss, and the cost effectiveness looks especially favorable among vulnerable populations. Conclusion: Improving indoor air quality really needs coordinated, interdisciplinary work that kinda links environmental science, building physics, and economic policy at the same time. Collaborative research and innovation are essential, because without them it is hard to design interventions that are scalable and also cost effective. When we prioritize IAQ improvements, it becomes a critical public health strategy, for supporting healthier residential environments.