A Novel Statistical Framework for Quantifying Industrial Impact on the Spatial Distribution of PM2.5

Industrial development has significantly contributed to economic growth and modernization, but it has also intensified a range of environmental challenges. Among these, air pollution has emerged as a major concern because of its strong implications for ecosystem stability, climate related stress, and public health. In particular, PM2.5 has received considerable attention due to its fine particulate nature, wide spatial reach, and well documented harmful effects. Although previous studies have extensively examined the relationship between PM2.5 and industrial or anthropogenic activity, direct quantification of industrial impact on PM2.5 remains methodologically limited, especially in data constrained regional settings. The present study addresses this gap by proposing a quantile mapping based statistical framework for quantifying industrial impact on PM2.5 across Pakistan. We called the proposed framework as - Baseline-Referenced Industrial Quantification of PM2.5 (BRIQ-PM2.5). The proposed framework BRIQ-PM2.5 is based on the comparison of observed PM2.5 distributions with province specific baseline reference conditions representing comparatively lower industrial settings. By aligning the PM2.5 distributions of target locations with their corresponding baseline cities through quantile mapping, the study estimates industrial impact as the excess burden reflected in the difference between observed and corrected PM2.5 levels. The proposed framework BRIQ-PM2.5 is applied across four provinces of Pakistan using satellite derived PM2.5 data. The results showed that the quantile mapping procedure effectively aligned the corrected PM2.5 series with the selected baseline conditions, as reflected in distributional summaries, histogram comparisons, empirical cumulative distribution function(ECDF) alignment, and improved RMSE values after correction. The resulting industrial impact estimates revealed clear spatial variation across stations and provinces, indicating that industrially aligned PM2.5 burden is not uniformly distributed. Further, spatial analysis based on variogram modeling and kriging demonstrated that the estimated industrial impact follows a coherent spatial pattern across the country. The study contributes a new methodological perspective to air pollution analysis by moving beyond simple concentration comparison toward baseline referenced industrial impact quantification. From a practical point of view, the proposed framework BRIQ-PM2.5 provides a useful statistical tool for hotspot identification, regional comparison, and geographically targeted environmental planning. The findings may support policymakers and environmental agencies in identifying areas where industrial influence on PM2.5 appears comparatively stronger and where more focused monitoring and mitigation efforts may be required. Flowchart illustrating the proposed framework for quantifying industrial impact on PM2.5 using quantile mapping and spatial analysis