Regarding Using Shipping Containers for Homes

When talking about alternative materials and forms for housing, the question of using shipping containers as structural framework often arises.  I have seen some examples of this, and apart from the basic problems of removing toxic residue, adding insulation, and solving flashing challenges, these could be a viable form of alternative housing forms. However, there’s one more consideration that might be worth investigating further.
From September of 2010 to September of 2012, I was the Program Manager of Green Initiatives courses at Palo Alto College in San Antonio. A colleague of mine was the Program Manager of industrial courses including courses related to Hydraulic Fracturing (Fracking) skills. His line of work included becoming familiar with activities at drilling sites. One day, he mentioned that they had discovered that a load of tracking sand delivered to one of these sites was measurably more radioactive than the usual delivery of sand. Just to keep this story short, they had determined that the fault wasn’t in the sand, but of the shipping container that delivered the sand to the site.  According to what I heard, which admittedly was second hand, radiation coming from the container itself contaminated the sand that was packed close to the walls of the container with the sand located closer to the center of the container was being shielded by the sand closer to the contaminated sand. They had therefore assumed the container at one time or another was in service in China or another country with nuclear capability (and lack of public oversight). This speculation included the possibility that the container was used to transport nuclear waste, either of the medical variety or even much more dangerous spent fuel rods from nuclear power plants. And then, like the millions of other non-descrip shipping containers, the contaminated shipping container was returned to the shipping channels totally undetected.
This story seems possible, but I had thought that somewhere, someone would have been more diligent with regard to detecting “hot” containers making their way to American ports. I wonder, in the years since 9/11, if American ports ever managed to put into place strategies to scan 100% of incoming containers for radioactivity. I would imagine that if indeed containers could be so contaminated by being used to haul poorly shielded spent fuel rods between power plants and some remote dumping ground, that the containers themselves could be as dangerous as mobile “dirty bombs” whether or not they were intended to be used in that way.
I’m not currently proposing anything related to more global-political-mercantile issues. I’m just putting this admittedly speculative tale out there just as something you may want to consider if you are considering living in a shipping container someday. I would think at the very least that finding or borrowing or renting a geiger counter before purchasing a shipping container might be a good idea.