One of the Earth's most precious and fragile marine habitats is being forced to swallow a toxic stew of crude oil, raw sewage and radioactive waste. Countries bordering a corner of the North Pacific ocean have been hamstrung over how to clear up the mess. Now they are gearing up for a deal aimed at saving their common sea. This week's Earth Report looks at the need for a pact on The Sea.

Home to a spectacular array of some of the Earth's most unique and endangered wildlife, the Northwest Pacific sea is also one of the world's busiest sea lanes. And it is slowly being engulfed by a wave of pollution.

Deep historical splits between key countries in the region have stalled attempts to stem pollution flows using a regional agreement. But since the United Nations stepped in, the prospect of a deal to save the largely-enclosed body of water looks brighter.

FROM BATTLES TO BOOMS

While it took just one year for countries bordering the Mediterranean to clinch the first-ever regional deal to protect their sea, a decade of talks between Japan, China, Russia and South Korea have produced little more than a name for their stretch of shared water - The Sea.

Although other bitter enemies have overcome years of tension to sign up to regional sea pacts - eight have been signed in the last 25 years - power struggles over land and resources in East Asia during the last century have left a legacy of deep-seated mistrust, with North Korea remaining a last outpost of the cold war.

The end of the Cold War saw dramatic economic changes sweep across the region. A trade boom sidelined stiff enmities and fostered closer regional ties, transforming the area into a dynamic commercial hub.

But while greater affluence across East Asia has not worn away all the staunchly-held grudges, a menacing side-effect of the economic boom has made a regional link-up more urgent.

RED TIDES

New offshore oil platforms and increased tanker traffic are piling pressure on the region's fragile ecological balance. With about 40 per cent of the world's shipments of petroleum being carried along the Northwest Pacific seaway, there are more than a dozen major oil leaks every year.

Coastal urban centres - like Shanghai in China - pump nitrogen-rich sewage into the water, causing red tides. And in the early 1990s a Russian military reporter exposed on film a radioactive waste dumping ground in the Northwest Pacific.

It is not only fishing communities who suffer. The region's population is overwhelmingly reliant on fish. East Asians derive nearly 30 per cent of their protein from fish. Japanese and Koreans eat between four and five times the world average of seafood.

So a deal to save the sea from the scourge of toxic waste is not only important for the flora and fauna of the region. It is also crucial to the well-being of local people.

RULING THE WAVES

Sponsored by the United Nations Environment Programme, a regional seas agreement for the Northwest Pacific would lift cumbersome border controls between neighbours so they could act swiftly to tackle environmental emergencies.

The Northwest Pacific Action Plan has been drawn up to help frame a pact to shelter marine coastlines. An agreement would use joint action to tackle overfishing, stop polluted mudflats being reclaimed for agricultural use, and draw up plans for oil spill recovery and other environmental hazards. It would also set up a regional rapid response force to seal off oil slicks.

Although talks on the action plan have dragged on for 10 years without agreement, the meetings have awakened hopes that the tide may be turning and that a future bid to rescue the ailing sea will pay dividends for the region's next generation.