It’s no secret that scrubbers are emitting harmful gases and contaminating our eco systems and fragile oceans with poisonous washwater, lowering the pH value and damaging all aquatic life. Because of this, we have advocated for a long time that open loop scrubbers should be banned, and failing that, stricter regulations on the overall use of scrubbers should be mandated.

Ocean acidification remains a big concern!  

Promoted as “green” and good for the environment, these destructive open loop scrubbers produce a discharge of washwater that isn’t disposed of properly due to the expensive cost to do so, making it a major contributor to the drastic change in seawater pH levels.

Studies are showing that high-Sulphur fuels used by vessels with polluting scrubbers are producing higher emissions of hazardous substances including metals such as Copper, Zinc, Fluorene, and other polycyclic aromatic hydrocarbons (PAHs) compared to fuel alternatives such as marine gas oil (MGO). These toxic substances are continuously dumped into our oceans in high concentrations of up to several hundred cubic meters of water through scrubber washwater in a matter of hours.

The pH of seawater has dropped significantly since the industrial revolution from an average of 8.2 to an average of 8.1, which might not seem like much of a difference until the relationship between pH and acidity is considered. Each decrease of one pH unit is a ten-fold increase in acidity.This means that the acidity of the ocean today is about 25% greater than it was during preindustrial times.

It has taken a long time, but finally some countries such as Australia, Egypt, and China have started restricting or entirely banning the discharge of washwater due to large concentrations of the aforementioned contaminants found in their heavily trafficked global trade ports. Data from Copenhagen and Gdynia, for example, showed five and thirteen times the limit of acceptable contaminant concentration. Other countries such as Argentina have suspended their previously imposed prohibitions on washwater discharge and need to be called out.

 How many more studies do we need before all countries completely ban lethal scrubbers?

 For a list of countries with restrictions or total bans on scrubber wash water, visit: Britannia-List-of-Jurisdictions-restricting-or-banning-scrubber-wash-discharges-2022-11.pdf(safety4sea.com).

Sources:

1.      Swedishscrubber discharge study makes case for stricter regulations - Splash247

2.      IMO2020 – cutting sulphur oxide emissions

3.      The impactof scrubber discharge on the water quality in estuaries and ports |SpringerLink

4.      Understandingthe Science of Ocean and Coastal Acidification | US EPA

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