Location of global scrubber washwater discharges by distance from the shore 2020
Scrubber washwater is a byproduct of vessel scrubbers. These are employed to remove nitrogen oxides (NOx), sulfur oxides (SOx), and other air pollutants from exhaust gases generated by engines, usually by spraying sea water over exhaust gases. This mixture of seawater and pollutants removed from exhaust gases - called scrubber washwater - is then discharged overboard. Scrubber washwater can seriously harm marine organism.