Nippon Paint Marine announced that results from a recent independent study shows that its AQUATERRAS hull coating had no negative impact on the marine life tested – including zero mortality among marine invertebrates – following simulated in-water hull cleaning.

The trial, conducted by the independent laboratory PML Applications Ltd. and concluding in August 2024, exposed marine organisms in estuarine sand and mud to flakes of the AQUATERRAS biocide-free self-polishing coating.

AQUATERRAS is a low friction, biocide-free, self-polishing coating that provides a long-lasting smooth hull surface for up to 90 months and provides up to 14.7% fuel savings compared to market average. In-water cleaning has become a greater feature of on-going hull maintenance, as awareness of the fuel saving benefits of reduced friction between hull and water has increased.

While the IMO’s best management practice requires in-water cleaning operators to be aware of local regulation regarding the discharge of biofouling and waste substances into the marine environment, particle abrasion is an unavoidable outcome of the process, which may cause risks to marine life.

“In this study, we were commissioned to independently assess the impact of five different types of marine coating particles, including AQUATERRAS, on selected marine life, and also to characterize the physical effects of in-water cleaning on the integrity of the various coatings,” Dr. Tom Vance, COO of PML Applications, the commercial arm of Plymouth Marine Laboratory (PML), said.

“Our tests showed no adverse effects on either ragworms or bivalve cockles after 28 days of exposure to AQUATERRAS coating particles,” Dr. Vance added. “The bivalves continued to gain weight and grow, with no significant difference in growth rates compared to the control group. Similarly, ragworms gained weight throughout the 28-day trial with no significant differences from controls.”