On Sunday, iodine-131 measuring 1,850 times the legal maximum were reported a few hundred metres (yards) offshore, up from 1,250 times the limit Saturday, but officials ruled out an immediate threat to marine life or to seafood safety.
A 9.0 magnitude earthquake and tsunami on March 11 knocked out the cooling systems of the Fukushima plant's six reactors -- triggering explosions and fires, releasing radiation and sparking global fears of a widening disaster.
News that makes sense
Your trusted source for staying up-to-date with the world around you. Get free daily news updates and analysis, straight to your inbox.
Radiation from the plant northeast of Tokyo has wafted into the air, contaminating farm produce and drinking water, and seeped into the Pacific Ocean.
