Actually, there “is” nothing to see here. It is obvious from the fact that the radioactivity is Co60 that some scavengers stole a radiography apparatus from some pipeline construction site and turned it in as scrap metal. It got melted down and incorporated with a bunch of other scrap as cheap steel. It’s happened before in the US, so the problem isn’t unique to China.
Sorry, came across this due to another thread on the cheese grater...
The working assumption is that you don't worry about it, since you are not *cheap* steel, right? (see your tagline).
Cheers!