Spills during ammonia’s use as a shipping fuel would be most dangerous to fish in warmer and less saline waters, a report has found.

The study into the potential marine environmental impacts from bunkering operations, ship collisions and sinkings found estuaries, mangroves and wetlands are particularly sensitive to potential ammonia spills compared with the polar regions and deep sea.

“Within these habitats, it is typically fish which are most sensitive to an ammonia spill, with birds and mammals to a lesser degree,” said the report from the Environmental Defense Fund (EDF), Lloyd’s Register and environmental and engineering consultancy Ricardo.