here is what I surmise:
Nuclear material has a LOOOOOONNG life.
While the ocean is vast, there are many artificial sources dumping, in some cases, TONS of that material into the ocean and the culprits all say: "Don't worry, it's just a small amount and the ocean is a big place"...
BUT, it is a closed system, the world. And these particles, while might not be too dangerous when swimming and brushing up against them, wouldn't be so good if ingested.
I was reading about this kind of shiite back when Fukushima had just exploded (another on-going source of pollution)... as a lay person with no medical training other than what I picked up watching Marcus Welby as a kid... there was an explanation that caught my ear that explained such a risk saying that a single particle being ingested and then incorporated into the muscle mass of the organism that ate it... that particle lodges in your aorta (or wherever) and it keeps sending it's little poison pills out into the surrounding tissue. Their claim was that it could spark cancer or even heart disease (if lodged in one's heart)
Now I understand that there are many NATURAL sources of radiation. But I also am given to understand that the effects of radiation are cumulative...so there is no merit in adding to those sources(?)
Now Iodine concentrates in the Thyroid. That's why one is supposed to take (non radioactive) iodine well in advance of exposure in order to saturate one's thyroid with untainted iodine preventing the absorption of radioactive iodine. Follow?
Remember the tritium watch dials? Tritium wasn't so bad worn on your wrist, but if you swallowed it... it became a part of you and ... the watch dial makers used to paint the watch dial tick marks, if you will, with little tiny paint brushes... well those little marks on the watch dial are TINY and one needs a very pointy brush to paint them neatly...so they would form the point on their brushes by licking them or pressing them between their lips... presto CANCER.
So, let's say you like to eat ocean fish...and that fish has been eating stuff which wallows around in ocean sediments and has sucked up some of this radioactive iodine...and then you eat the fish... are you picking up what I'm putting down.
In this case, MORE is NOT better.
but I'm just a carpenter. You make your own call.
here's some reading:
https://www.ncbi.nlm.nih.gov/pmc/articl ... 87/?page=1