The crew of a catamaran made from plastic bottles and about to complete a Pacific crossing said Friday they hoped their odyssey would highlight the danger that plastic waste poses to the oceans.
The mainly British crew of the Plastiki -- a pun on the Kon-Tiki raft Norwegian explorer Thor Heyerdahl used in his 1947 Pacific expedition -- is expected to arrive in Sydney next week after a four-month voyage.
"We have this addiction to single-use, throwaway plastic, which is choking up the ecosystem," expedition leader David de Rothschild said in a Skype link-up with Achim Steiner, head of the Nairobi-based UN Environment Programme.
"With Plastiki, we want to enlighten, inform and inspire people and show that there are solutions here and not just problems."
The catamaran's hull is made from 12,500 recycled plastic bottles glued together with an environmentally-friendly adhesive made from cashew nuts and sugar, UNEP said in a statement.
The Plastiki's 10-strong crew left San Francisco in March and sailed through the North Pacific gyre, a swirling 3.5-million-tonne mass of waste which is roughly the size of Texas and better known as the Great Pacific Garbage Patch.
"We’ve spent four months at sea but have seen very little fish stock and only a handful of marine mammals," de Rothschild said. "That is a real sign that the oceans are in desperate need of our help."
The crew was inspired to undertake the voyage after reading a 2009 UNEP report that found that 13,000 pieces of plastic waste are floating on every square kilometre of ocean and that eight million pieces of litter enter the world's oceans every day.
Explore further: Dead floppy drive: Kenya recycles global e-waste