Fukushima:
"As of 2014, a peer reviewed estimate of the total was 340–800 PBq, with 80% falling into the Pacific Ocean.[8] Radiation continues to be released into the Pacific via groundwater."
So it's a magnitude (though still in progress) and "luckily" most of the damage went to the ocean. Now how much sea life and derived food is contaminated is anyone's guess and what the long-term consequences on ocean ecosystem from continuous flow of radioactive particles will be is an interesting question.
