Effects of ambient air pollution from shipping on mortality: A systematic review

Shipping contributes to air pollution causing adverse health effects. We conducted for the first time a systematic review on the health and economic impacts of ambient air pollution from shipping emissions.

We performed a systematic search in PubMed, Web of Science, EBSCO (Medline), and Scopus of all time up to December 2023. We then inter-compared semi-quantitatively the results of the included eligible studies.

We identified 23 eligible studies, 22 applying health impact assessment, and 1 using epidemiological methods. These studies used different methods for the evaluation of emissions, dispersion, and exposure, and for the exposure-mortality risk functions for exposure to shipping emissions for 1-2 years. The estimated excess global all-cause mortality from six studies ranged between 1 and 5 deaths per 100,000 person-years. However, the heterogeneity of the methods and critical gaps in the reporting seriously limited the synthesis of the evidence on health and economic effects of shipping emissions. Sufficient spatial and temporal resolutions in both dispersion and exposure modeling, as well as presentation of uncertainties is needed. Health impact assessment should present the results with all the main risk functions and population attributable risks, and the magnitude of the effect should be expressed in excess number per a given person-time or per population size. Economic effects should also cover work productivity, mental well-being, and cognitive functions.

We recommend that future studies should properly evaluate and report the uncertainty ranges and the confidence limits of the results. Rigorous studies are needed on multipollutant exposures, exposures from various source categories, and exposures attributed to various particulate matter measures. Studies should report the health impact measures in a format that facilitates straightforward inter-study comparisons. Further research should also specifically report the used grid spacings and resolutions and evaluate whether these are optimal for the task.