Bioplastics
TL;DR: Bioplastics may not be tossed into the ocean. Alternatives exist
Background
Rather than using a through-hull plumbed head, some boats line a toilet or bucket with a bag and then toss the result. So-called “bioplastic” bags, while seemingly attractive for this task, are not appropriate. Although labeled “compostable” or “biodegradable”, they do not decompose in the ocean for a very long time, if ever. To make matters worse, these types of bags DO contain plastic, and, even if they break down in the ocean, micro-plastics will be released. Apparently, they only break down in commercial composting plants.
The Racing Rules of Sailing Rule 47
The Racing Rules of Sailing Rule 47 states "Competitors and Support Persons shall not intentionally put trash in the water. This rule applies at all times while afloat. The penalty for a breach of this rule may be less than disqualification"
The Pacific Cup 2024 Notice of Race includes:
11. [DP] RRS 47 is changed by adding the following sentence to the rule: “Beyond 3 nm from the nearest shore, a boat that discards or discharges (a) biodegradable sail stops when setting a sail, (b) biodegradable galley waste or (c) biodegradable head waste, shall be exonerated from breaking this rule. This changes RRS 47.
The Pacific Cup conclusion is that putting bioplastic bags or any other material containing plastic overboard violates RRS 47 even if labeled “compostable”.
Racing rules aside, tossing these materials in the ocean also violates US and International Law, including the International Convention for the Prevention of Pollution from Ships (MARPOL).
The document suggests some alternatives that can be used for this purpose.
Testing and Recommendations
In the search for some alternatives that don’t violate RRS 47, the Pacific Cup Technical Committee performed some testing of brown paper kraft bags [listed below]. The test included letting them sit in the water for several weeks near Richmond Yacht Club and separately at Kaneohe Yacht Club. A test was also done if they would hold liquid for a few minutes. These bags did disintegrate over the test time, somewhat faster in the warmer water near Kaneohe. They also passed the dreaded “liquid” test.
We conclude these bags or ones that are similar will work to dispose of waste overboard and don’t violate RRS 47.
Additional Resources
Do biomaterials break down in natural environments? https://www.5gyres.org/betteralternatives?mc_cid=19dbc9a2df
MARPOL Annex V - Provides basic information and compliance guidance regarding Garbage pollution prevention from ships.
Brown Kraft Twisted Handle Shopping Bag - 10 x 9.85 x 10 in.