Abstract
The IMO 2023 Biofouling Management Guidelines and 2025 guidance aim to prevent fouling on ships and minimize the spread of non-native species (MEPC 378(80)), by recommending in-water cleaning (IWC) with effluent treatment, ensuring that only particles, including organisms, smaller than 10 μm in all dimensions should be released.
The objectives of this brief literature study have been (i) to identify pathogenic microorganisms smaller than 10 μm that may occur as symbionts of macroorganisms fouling the hulls of marine vessels, and that could potentially be released under current guidance; and (ii) to identify the most relevant scientific knowledge gaps concerning pathogenic microorganisms associated with vessel biofouling.
This report shortly describes the methods used and provides examples of identified microorganisms (smaller than 10 μm) reported to be pathogenic. Knowledge gaps related to microorganisms associated with fouling of marine vessels is also shortly addressed.