A global multidimensional analysis of air pollution in land, sea, and air transport cabins reveals substantial health risks

Air pollutants are ubiquitous in transport cabins, contributing significantly to the burden of disease, but exposure levels and related health effects remain largely unexplored at a global scale. To address this, we systematically reviewed studies from the past 20 years on 17 air pollutants across major means of transport over land, sea, and air globally. We evaluated concentration levels from the perspectives of transport type, country, and time, and analyzed primary influencing factors and health effects. Findings showed that land transport provided the highest pollutant exposure, with that to bus drivers topping the list, while high levels of certain pollutants were also detected in sea and air transport. Although energy transitions have helped partly reduce benzene, toluene, and NO₂ exposures, levels of formaldehyde, black carbon, and particulate matter (PM_2.5 and PM₁₀) remain persistently high, indicating substantial health risks. This study enhances our understanding of cabin-related health effects and provides a foundation for effective exposure-reduction strategies.