One Planet Port has joined a coalition of environmental NGOs urging the International Maritime Organization (IMO) to prohibit ships from discharging toxic ammonia waste into the ocean. The coalition, including Environmental Defense Fund, Pacific Environment, and Clean Shipping Coalition, is calling for a precautionary approach where ammonia-fueled ships retain waste onboard and offload it at port reception facilities instead of routinely discharging it at sea. This position was presented during the IMO’s Pollution Prevention and Response Sub-Committee meeting in London (February 9-13 2026), where governments discussed how to manage ammonia effluent generated from ammonia-fueled ships.

Dr. Lucy Gilliam, Co-Executive Director of One Planet Port, emphasizes that this issue extends far beyond shipping. “The nitrogen cycle is already beyond safe planetary boundaries. We cannot afford to normalize another source of reactive nitrogen pollution as shipping decarbonizes.” Gilliam argues that focusing only on short-term toxicity misses the bigger picture: discharging ammonia introduces reactive nitrogen pollution to marine environments, contributing to eutrophication, oxygen depletion, and ocean acidification. “The industry has an opportunity to get ammonia fuel right from the start by retaining waste onboard and landing it ashore, rather than defaulting to ocean discharge. This isn’t just about toxicity – it’s about preventing further disruption to a critical planetary system that’s already under stress.” 

With 35–50% of ships projected to run on green ammonia in a fully decarbonized maritime future, One Planet Port warns that conditional discharge could quickly become routine with unknown long-term consequences for ocean health. The organization advocates for retaining ammonia waste onboard and landing it ashore, where it can potentially be reused by chemical or fertilizer industries, supporting a circular economy approach.

Find the full press release here.