A pro-scrubber group is urging ports worldwide against banning open-loop scrubbers on the premise that the IMO 2020 devices may harm marine life.

"Ports have the right to mandate their own requirements and it is commonplace for local administrations to continually assess their ship discharge requirements," Clean Shipping Alliance 2020 executive director Ian Adams said.

"But to link these decisions to sensationalist statements in the scrubber debate, without any reference to scientific data, is unfounded, unreasonable and impacts port clients while perpetuating the spread of factually incorrect information."