Update from Japan

Readings taken in the sea near the plant showed that levels of the radioactive isotope iodine 131 have continued to rise, testing at 4,385 times the statutory limit on Thursday, nearly four times higher than on Sunday, said Hidehiko Nishiyama, deputy director general of Japan's Nuclear and Industrial Safety Agency. That rise increases the likelihood that contaminants from the plant are continuously leaking into the sea, he said.

Iodine 131 was also detected at levels 10,000 times the safety limit in groundwater near Reactor No. 1.  Full article here. 

Some recent I-131 radiation readings: 

1.8 billion Bq/liter in water in the turbine building at Fukushima

400,000 Bq/liter in groundwater near the Fukushima plant

175,000 Bq/liter in seawater near the Fukushima plant

50 Bq/liter in drinking water in Tokyo

3.7 Bq/liter in rainwater in Pennsylvania

40 Bq/liter is legal limit for radiation in water