Health impact assessment of road traffic noise in two Japanese cities: A scenario study on annoyance and ischaemic heart disease based on noise maps

This study assesses the health impacts of road traffic noise in Osaka City (Tennoji Ward) and Higashiosaka City, Osaka Prefecture, using strategic noise maps. The ASJ RTN-Model 2018 was employed to estimate noise levels, and three noise reduction scenarios were analyzed: reducing light vehicle power levels, heavy vehicle level and installing porous pavement. The study also combined estimations of building occupancy from open data and noise exposure level, enabling assessments of noise health impact. Results of three scenarios and reference showed that approximately 10% and 5% of the population in Tennoji Ward and Higashiosaka City, respectively, are estimated to be suffering from high annoyance due to traffic noise. While noise reduction measures effectively decreased exposure levels, their impact on ischaemic heart disease incidence was limited, suggesting the need for more comprehensive mitigation strategies. The effectiveness of different scenarios varied between cities, highlighting the importance of considering local urban characteristics in noise management planning. This study demonstrates the practical application of strategic noise mapping for health impact assessment in Japanese cities and provides valuable insights for evidence-based urban noise policy development.