By sailing a plastic boat David de Rothschild is trying to highlight alternative uses for the material. Photo / AP

By sailing a plastic boat David de Rothschild is trying to highlight alternative uses for the material. Photo / AP

In a few weeks, the heir to one of the world's greatest fortunes, David de Rothschild, will set sail across the Pacific in the Plastiki, a boat made from plastic bottles and recycled waste.

The aim of the venture is to focus attention on the Great Pacific Garbage Patch, a rubbish-covered region of ocean, several hundred kilometres in diameter.

The patch, north-west of Hawaii, was discovered in 1999 by researchers who found that its waters contained tens of thousands of pieces of plastic per square kilometre, the remains of rubbish caught in the region's circulating ocean currents. This pollution is devastating populations of seabirds and fish that live in the region.

During his trip, which is being sponsored by the International Watch Company and Hewlett-Packard, de Rothschild will collect water samples and post blogs, photographs and video clips, to try to publicise the perils of plastic pollution.

To further highlight the plastic pollution problems, the 30-year-old environment crusader has designed a special catamaran with a hull made of frames filled with 12,000 plastic bottles.

The cabin and bulkheads of Plastiki have also been constructed out of a special recycled material called srPET, made of webs of plastic.

"The plastic water bottle epitomises everything about this throwaway, disposable society," said de Rothschild, who trained to be a showjumper in England and who has trekked to both the North and South Poles. However, he added that he was not aiming to demonise plastic, but was trying to highlight its alternative uses, as well as focusing global attention on the dangers posed to the ecology in regions such as the Great Pacific Garbage Patch.

The Plastiki - its name inspired by the balsa raft Kon-Tiki that was built and sailed across the Pacific in 1947 by Norwegian explorer Thor Heyerdahl - is undergoing trials in San Francisco harbour.

"The project has gone through several materials, exploring everything from bamboo to plywood, even playing around with the idea of sewing all the bottles together in one giant sock," said de Rothschild.

The 20m catamaran has cost several million dollars to construct and has taken three years to reach this design. It will carry de Rothschild and a crew of six on a 2720km journey from San Francisco to Hawaii, Midway Island, Bikini Atoll, Vanuatu and, finally, Sydney. There will be no accompanying craft, but the Plastiki will be met by a support team at each landfall.