European harbours are known to contribute to air quality degradation.While most of the literature focuses
on emissions from stacks or logistics operations, ship refit and repair activities are also relevant aerosol
sources in EU harbour areas. Main activities include abrasive removal of filler and spray painting with antifouling
coatings/primers/topcoats. This work aimed to assess ultrafine particle (UFP) emissions from ship
maintenance activities and their links with exposure, toxicity and health risks for humans and the aquatic
environment. Aerosol emissions were monitored during mechanical abrasion of surface coatings under
real-world operating conditions in two scenarios in the Mallorca harbour (Spain). Different types of UFPs
were observed: (1) highly regular (triangular, hexagonal) engineered nanoparticles (Ti-, Zr-, Fe-based),
embedded as nano-additives in the coatings, and (2) irregular, incidental particles emitted directly or
formed during abrasion. Particle number concentrationsmonitored were in the range of industrial activities
such as drilling or welding (up to 5 ∗ 105/cm3, mean diameters <30 nm). The chemical composition of PM4
aerosols was dominated by metallic tracers in the coatings (Ti, Al, Ba, Zn). In vitro toxicity of PM2 aerosols
evidenced reduced cell viability and a moderate potential for cytotoxic effects. While best practices
(exhaust ventilation, personal protective equipment, dust removal) were in place, it is unlikely that
exposures and environmental release can be fully avoided at all times. Thus, it is advisable that health
and safety protocols should be comprehensive to minimise exposures in all types of locations (near- andfar-field) and periods (activity and non-activity). Potential release to coastal surface waters of metallic
engineered and incidental nanomaterials, as well as fine and coarse particles (in the case of settled dust),
should be assessed and avoided