The admission comes in a report by a high-level committee headed by President Boris Yeltsin's top environment advisor Alexei Yablokov, established to investigate the Russian Navy's nuclear dumping since 1959.
It found that the navy's northern and Pacific fleets have been dumping obsolete nuclear submarines for more than 30 years and that many were dumped with radioactive fuel supplies on board.
Greenpeace officials, who were given a copy of the report, believe it may now be too late to prevent the radioactive reactors contaminating the food chain. They believe humans will inevitably be affected through the consumption of fish.
It is believed that 20 nuclear reactors have been dumped in the Arctic Ocean and Sea of Japan. The authors point out that the disposal of radioactive waste was not a priority during the nuclear arms race between the former Soviet Union and the United States. 'The simplest solution was the disposal of waste in the seas,' it states.
John Large, a consulting nuclear engineer and advisor to Greenpeace welcomed the report. 'It is a disaster out there,' he said. 'The state of the Russian Navy is so disorganised. They have taken no account of this problem. They have been forced to dump radioactive waste at sea. Once it gets into the marine environment there are going to be real problems monitoring it in fish stocks.
'There is no doubt it will get out sooner or later. It will start leaking and once it does it cannot be vacuumed away. Russia does not have the capital or technology to make their nuclear submarines safe.'