Industrial activity, traffic congestion, and health vulnerability in Java, Indonesia: a spatial spillover analysis

Health vulnerability assessments are essential in countries with high pollutant exposure, such as Indonesia. The main objective of this study is to construct a health vulnerability index (HVI) related to air pollution and climate condition and analyze its spatial relationship with industrial activity and traffic congestion using large-scale geospatial data. The study utilized secondary data from satellite images, official statistics, and OpenStreetMap. The index was developed through principal component analysis (PCA), followed by spatial regression to assess its association with the industrial activity intensity and traffic congestion level. The results indicate that the HVI scores range from 29.2 to 62.3 on a scale of 0-100, with the highest vulnerability found in West Java, Jakarta, and Banten, while regions such as Central Java, Yogyakarta, and East Java show lower vulnerability. The developed HVI has been tested for robustness through uncertainty and sensitivity analysis and has proven effective in representing health vulnerability to air pollution and climate at the regional level. The exposure dimension of the HVI varies the most with a score of 13.18, while adaptive capacity scores 9.40 and sensitivity scores 5.17, showing that different areas have different values. The spatial Durbin model (SDM) regression results indicate that HVI is influenced by industrial activity intensity and traffic congestion through both direct (local) and indirect (spillover) effects.