Challenges in removing single-use plastics from ships

The IMarEST’s Ocean Plastics and Marine Litter Special Interest Group is investigating options for eliminating single-use plastics on board.

Designed to be used only once (or for a very short period), single-use plastic products are often regarded as the embodiment of our throwaway culture. Once we discard them, single-use plastics typically end up in landfills and incinerators, as well as in our forests, parks, towns, beaches, and the ocean. Single-use plastics are everywhere, including on recreational and maritime vessels, big and small. And regardless of industry, the Ocean Plastics and Marine Litter Special Interest Group (OPMLSIG) has learned that plastic bottles are one of the most common single-use plastics found on board ships.

Bottles on board

Access to potable water is of paramount importance, especially when at sea for long periods. Many larger vessels used by industries such as cruise, cargo, and defence, as well as some larger yachts, have the equipment to produce drinking water from seawater or have purpose-built tanks to store freshwater between port visits. In either case, the water must be treated to ensure it is safe to drink. 

Chlorine is the most commonly used method to treat water, but as industry representatives highlighted to the OPMLSIG, it is notorious for leaving an unpleasant taste in the water. Industry representatives also noted that bad taste sometimes occurs with seawater-to-freshwater systems, especially when the systems aren’t maintained to a high standard. 

In discussions with representatives of the yachting, cruise, and passenger ship industries, all highlighted how the taste of water was a particular concern for their clients, who tend to pick bottled water over water from taps and fountains. Other industries also highlighted how vessel crew members often preferred bottled over tap water for the same reason.

The tendency for crew and clients to shy away from tap water isn’t entirely down to taste preferences. Industry representatives also noted health concerns, even when water is treated correctly. Whether real or perceived, the risk of sickness or worse from contaminated water is a major concern.

In an ideal world, plastic bottles wouldn’t be used, but the taste of treated water is a particular concern (Credit: Shutterstock)

Recycling plastic bottles

Although in an ideal world, plastic bottles wouldn’t be used at all, there is one silver lining: they can often be recycled. However, there are practical challenges to ensuring bottles reach recycling facilities.

Space on board vessels almost always comes at a premium, and older vessels, in particular, have not been designed to collect and store multiple different waste streams. This presents a very real practical problem for vessels wanting to recycle as much waste as possible. For those that can separate their waste, the problem doesn’t end there. Although private boat owners may be able to take their waste home for recycling or drop it off at an external facility, this is not practical for most industry vessels. For these vessels, ports are the primary gateway between them and waste disposal and recycling facilities. 

Industry representatives highlight how port facilities are highly variable. Some may accept multiple different materials for recycling, some may only take one or two. Some may offer no recycling options. To complicate the situation, the industry representatives noted that ports that handle recyclable materials often have different sorting requirements. Furthermore, many ports do not provide clear signage about their waste facilities in the ports themselves.

Moving forward

Following on from my presentation at the International Marine Debris Conference, OPMLSIG has begun discussions with several other organisations to reduce single-use and other plastics on vessels and improve recycling. The SIG is currently considering activities and collaborations with other groups to tackle the single-use plastic crisis. 

Stephanie Lavelle was in conversation with Sam Andrews

To become a member of the Ocean Plastics and Marine Litter SIG, log into My IMarEST, click on My Special Interest Groups and then tick the boxes of the SIGs you'd like to join. You can then also join the group on Nexus, our networking platform."