Tehran University of Medical Sciences Journal of Air Pollution and Health 2476-3071 11 3 2026 09 13 395 410 Oluwaseun Dosunmu Department of Physics, Lagos State University of Education, Lagos, Nigeria Augustine Ademola Department of Physical Sciences, Bells University of Technology, Ota, Nigeria Inioluwa Olowofila Department of Physical Sciences, Federal Polytechnic, Ota, Nigeria Peter Abodunrin Department of Physical Sciences, Bells University of Technology, Ota, Nigeria Babatola Funso Aina Department of Physical Sciences, Bells University of Technology, Ota, Nigeria 2024 12 06 2026 07 01 Introduction: Indoor air pollution is a growing public health concern, particularly in communities near industrial operations. This study evaluated indoor concentrations of fine and coarse Particulate Matter (PM2.5 and PM10) and radon in residential buildings located near cement factories in a selected town in Ogun State, Nigeria. The primary aim of this study was to investigate the concurrent indoor exposure to PM2.5 and PM10 and radon gas in residences near cement manufacturing facilities, quantify the associated non-carcinogenic and carcinogenic health risks, and examine the correlation between these co-occurring pollutants. Materials and methods: Air quality measurements were carried out in 20 residential buildings near cement plants. PM2.5 and PM10 levels were measured using the Elitech Temtop LKC-1000S+ air quality monitor, while indoor radon concentrations were assessed with CR-39 solid-state nuclear track detectors. Particulate matter sampling was conducted twice daily over 30 consecutive days, while CR-39 detectors were deployed for a 30-day exposure period. Health risk evaluations followed standard models for both non-carcinogenic and carcinogenic assessments. Correlation analysis was conducted to examine the relationship between particulate matter and radon. Results: Mean indoor concentrations of PM2.5 and PM10 were 39.94 μg/m³ and 60.83 μg/m³, respectively, both above WHO limits. Radon concentrations averaged 92.48 Bq/m³, with 40% of sampled homes exceeding the WHO recommended level of 100 Bq/m³. Hazard quotients for PM2.5 ranged from 2.3 to 3.0 and for PM10 from 1.0 to 1.5, yielding an average hazard index of 3.89. Elevated annual effective doses and excess lifetime cancer risks were also associated with radon. A positive correlation was found between particulate matter and radon levels. Conclusion: The study reveals a significant combined health risk from PM and radon exposure in homes near cement factories. Targeted mitigation, improved regulation, and public health awareness are urgently needed to reduce exposure and protect residents.   https://japh.tums.ac.ir/index.php/japh/article/view/863 https://japh.tums.ac.ir/index.php/japh/article/download/863/481