National-Scale Estimation of Brake-Wear Particulate Emissions From On-Road Vehicles in Türkiye: A 2024 Inventory with Uncertainty and Mitigation Scenarios

This research article develops a screening-level national inventory of airborne brake-wear particulate emissions from on-road vehicles in Türkiye for the year 2024. The scope is limited to brake wear only and does not include tyre wear, road wear, resuspension, or concentration and exposure modelling. The inventory combines TurkStat vehicle-kilometre statistics with EMEP/EEA Tier-2 brake-wear emission factors, including passenger-car powertrain differentiation to reflect regenerative-braking effects. Under nominal baseline assumptions, annual emissions are estimated at 5.67 kt·y-1 for PM10 and 2.26 kt·y-1 for PM2.5. Monte Carlo framework that propagates bounded uncertainty in total activity, vehicle-category composition, passenger-car powertrain shares, guidebook-anchored emission factors, and particle-size fractions, the national totals are characterised by a median (95% interval) of 5.67 (4.87–7.19) kt·y-1 for PM10 and 2.26 (1.87–2.90) kt·y-1 for PM2.5 Passenger cars account for approximately 45% of national PM10 emissions, followed by light commercial vehicles and tractor units. Illustrative, assumption-dependent scenario analysis indicates that PM10 could decrease to 4.95 kt·y-1 under partial uptake of low-emission brake technologies, to 5.28 kt·y-1 with greater use of auxiliary braking in heavy-duty vehicles, and to 5.47 kt·y-1 under a passenger-car fleet share of 10% HEV and 10% BEV. These scenario outcomes should be interpreted as indicative screening-level projections rather than empirical or policy-evaluation results. Overall, the study provides a transparent brake-wear-only national baseline and a comparative framework for examining how selected assumptions influence estimated PM emissions in Türkiye.