Based on a study conducted by Dutch institute CE Delft, Germany’s NABU suggests the ecological risks of the use of the cleaning systems are ignored.

Many shipowners have adopted this technology in order to comply with sulphur emissions rules that were introduced on 1 January.

Leif Miller, chief executive officer of NABU, said: “What came as a bad surprise is that obviously nobody ever systematically investigated the impact of scrubbers on the marine environment before entitling this technique as a proper solution in the European Sulphur Directive.

“At