In-water cleaning can clear-off foulants from ship hulls to prevent transportation of non-indigenous species and reduce hull friction and consequent fuel use. However, during cleaning, antifouling paint residues containing toxic substances can be released into the environment. To understand the potential risks of in-water hull cleaning, cleaning effluents were collected and analyzed for total suspended solid (TSS), particle size distribution, and metal concentrations. TSS concentrations were 97.3–249 mg/L, corresponding to release rates of 12.9–37.5 g/m² from the hull surface. Particles with sizes of ≥8 μm contributed 75–94% of the TSS. Average Cu and Zn concentrations in the effluents were 209 μg/L and 1510 μg/L, respectively, which were used for risk assessment in two port scenarios. Although the risks vary with the scale of the hull cleaning and the ports, in-water cleaning poses clear risks to marine environments, unless the effluents are recovered or treated before being released.

水下清洁可以清除船体上的污垢，以防止非本土物种的运输，并减少船体摩擦和随之而来的燃料使用。然而，在清洁过程中，含有有毒物质的防污漆残留物可能会释放到环境中。为了了解水下船体清洗的潜在风险，收集并分析了清洗流出物的总悬浮固体 (TSS)、粒度分布和金属浓度。TSS 浓度为 97.3–249 mg/L，对应的释放率为 12.9–37.5 g/m ²从船体表面。粒径≥8 μm 的颗粒贡献了 75-94% 的 TSS。流出物中的平均 Cu 和 Zn 浓度分别为 209 μg/L 和 1510 μg/L，用于两个港口情景的风险评估。尽管风险因船体清洁和港口的规模而异，但水下清洁对海洋环境构成明显风险，除非在排放前回收或处理污水。