Not only that, water released from Fukushima wouldn’t even go into the Sea of Japan. Fukushima is on the east coast of Japan. Water released from it would be going into the Pacific.

Hey, I'm trying to contribute to the World News with some stuff and because I live close by (in Korea) I found it interesting.

I'm very rusty here, so please correct me where I'm wrong.

Isn't most of the radiation that makes it to the earth's surface from the sun just EM radiation? That acts a lot different than radiation due to nuclear decay. Your use of the unit 'tons' makes me think you're talking about particle radiation, of which the only one that reaches earth's surface in large quantities would be muons, which may as well be ignored because they aren't interacting with anything.

The water being released by Japan has the following isotopes:

All four of these isotopes decay via beta decay.

So, a comparison to the Sun seems weird here.

Here's an IAEA overview as of February 2023,

The discharge of the ALPS treated water into the sea will be conducted after i) purification/re-purification to meet regulatory standards set based on international standards with an exception of tritium and ii) to allay the concerns of the consumers, the target concentration of tritium should be the same as the operational target (less than 1,500 Bq/L, that is less than 1/40 of the regulatory standard value for tritium) by sufficient dilution (more than 100 times) by sea water, prior to the discharge into the sea, and iii) The total annual amount of tritium to be discharged will be at a level below the operational target value for tritium discharge of the Fukushima Daiichi NPS before the accident (22 trillion Bq/year).

So it's diluted well below internationally accepted concentrations. Moreover, the release is even less than when it was operational!

The released water has around 1500 Bq/kg. If you were to drink a cup of that water (not even diluted further), you’d get a dose of 0.375 mSv. That’s like 100 flight hours, or an x-ray (depends). Two months of just sitting at home will get you that dose.

That's a weird comparison, isn't the concentration in one place which makes radioactive materials dangerous? (Not saying that the water has enough radioactive material, just saying that comparing it to the sun and the whole world doesn't make sense).

What's more, it's cleaner than when Fukushima was operational!

The total annual amount of tritium to be discharged will be at a level below the operational target value for tritium discharge of the Fukushima Daiichi NPS before the accident

Probably a reaction to the enormous over-reaction that people have been having about nuclear power for decades. People hear the word "radioactive" and freak out like it's some kind of evil spirit. It gets quite frustrating and tiring.

Fukushima in particular seems to be a touchstone for nuclear paranoia. 18,000 people died in that tsunami and zero of them were caused by the reactor meltdown, but there was a parade of news articles about how the Pacific Ocean was going to become some sort of septic dead zone and the entire coast would have to be evacuated. I recall one breathless prediction of the literal end of humanity. I really want to never hear of it again unless something actually significant happens.

Yeaaaahh, I didn't mean to upset OP with my bad pun but I think I did. Sometimes humor is no pun!