Algae munching fish clean up Chinese lake

Chinese authorities are using algae-munching fish to clean up one of the country's most polluted lakes -- and after their diet of toxins they will be sold on to consumers, state media said Thursday. More than 50,000 silver carp fry have been introduced into Chaohu lake and another 1.55 million will be added in the next 20 days, said Wu Changjun, from the Chaohu Fishery Administration, according to the Xinhua news agency.Each carp is expected to have gobbled between 40 and 50 kilogrammes (88 to 100 pounds) of blue algae when it reaches its adult weight, with each chomp of the sludge helping to clean up the toxic lake, the report added.Once the carp have matured, fishermen will be able to catch them and sell them in markets, at a price 15 times their original cost, giving a boost to the local fishing industry, according to Xinhua.Chaohu, China's fifth biggest lake in the nation's eastern Anhui province, was last year overcome by the blue-green foul-smelling algae, threatening water supplies and destroying life in the lake.The algae has led to a decline of 20 percent in the lake's whitebait stocks, one of the local fishing industry's key catches, Xinhua said Thursday.Hundreds of factories discharge their waste into Chaohu.More than 70 percent of China's waterways and 90 percent of its underground water are contaminated, according to government figures, often as the result of years of untreated sewage discharge and industrial pollution.The environmental woes have had led to problems with the nation's food supply, with some of those toxic foods making their way into exports that have contributed to the recent tarnishing of the "Made in China" brand.