Worms have been nature's recyclers for millions of years. Now they face a new challenge - cleaning up the city's mountain of fast-food waste. A firm is harnessing worm power to convert food and paper waste into organic fertiliser, and has set up a plant in Yuen Long offering a recycling service for take-away outlets. Sunburst Biotechnologies has won a key contract with McDonald's Hong Kong and is breeding 80 million red worms to start munching their way through leftovers and packaging early next month. The plant will initially process waste from eight branches in the western New Territories, and the programme will be expanded to more than 100 McDonald's restaurants early next year. Three catering firms have also signed up. 'The beauty of this process is that it is taking advantage of a natural process that has been going on for a billion years. The species we are using - Eisenia fetida - is native to Southeast Asia,' said Sunburst executive director Tse Chi-kai. 'We bought a tonne of the worms almost a year ago and we now have seven tonnes - or about 60 million worms. They double in number every six to eight weeks.' 'We have had a very good response from the big waste generators,' Mr Tse said. The firm has done a 'waste audit' of the eight restaurants and found that 80 per cent of the waste is organic. All this will be recycled into organic fertiliser that can be used for organic farming, soil conditioning and landscaping. 'The other 20 per cent is plastic packaging, which can be recycled by other centres,' he said. Mr Tse said the city's fast-food waste now went to landfills, which were expected to be full within six years. As organic waste rots in the sites, it releases the greenhouse gas methane. 'We will reduce waste-dumping to landfill by at least 50 tonnes a day from the outset,' he said.'We expect to extend the lifespan of landfills and indirectly reduce the amount of greenhouse gases.' A spokeswoman for McDonald's said participating restaurants would next month start separating leftovers, paper bags and other packaging from non-organic waste before throwing the rubbish out. The novel recycling process was developed in Australia in 1999 by Sunburst and Ohio State University. It has been accredited by two agriculture groups. Sunburst is seeking their certification for the Yuen Long plant. Kadoorie Farm is running a pilot project using 12,000 earthworms to recycle domestic food waste from Hong Kong housing estates.