The Academic Pipeline Stall: Why Industry Must Stand for Academia

How mildly?

Background radiation is a thing.

Granite and bananas are a tiny bit more radioactive than typical things, without making them dangerous.

I have absolutely no idea, but it is in interesting question and until someone more cluey can chime in a quick search suggests:

- Florida is using photogypsum - https://www.ijpr.org/npr-news/2023-06-30/florida-moves-forwa...

- Photogypsum in the US is banned if it radiates at >0.4 Bq/g of 226 Ra. https://en.wikipedia.org/wiki/Phosphogypsum

- Granite radiates at maybe 450 Bq/kg -> 0.45 Bq/g of 226 Ra. https://www.nature.com/articles/jes200944

So it looks like we're dealing with pretty standard rock. If this stuff was going to be banned without special permitting it is probably a little more risky than a granite kitchen-top counter if someone goes and sits on the road all day. Although this all raises the question of whether granite should be legal as a building material given that people get twitchy about this stuff - I doubt anyone can prove that granite is safe in this context.

Maybe abrasion creating dust to be inhaled by humans makes the difference here.

I expect it to — roads wear down and need resurfacing often enough, and that stuff has to go somewhere, either into the air as dust or dissolved in the rain and run off into the soil.

It's plausible, but I think the experience thus far is any dust in the lungs is a health risk. Asbestos will not be soon forgotten.

I'd be more worried about testing phosphogypsum's mechanical properties before anyone starts testing the radioactive ones. And danger relative to tyre rubber; although that has probably already been studied somewhere since it is an obvious thing to check.

Background radiation isn't the same as breathing in dust.

If this dust is as radioactive as granite dust then its radioactivity is likely not a problem. (breathing in that dust may be a problem despite radioactivity itself not being an issue) Or maybe I am wrong and breathing in granite dust is more dangerous as it is more radioactive than some other stones?

It is 10 000 times more radioactive - then it likely is a problem.

The question is which one applies. Typical bananas are not dangerously radioactive despite being unusually radioactive for a food product.