This blog from Santa Monica, CA, covers radiation monitoring in the US, and how to find radiation-free food at the supermarket:
Even though Denise Anne and I have radically adapted our diet to the new realities of radiation contamination, searching out pre-March 11 produced items, finding food grown south of the Equator, growing our own and knowing which foods currently on the grocery shelves were made with last summer’s harvest, most corn being an important example.
We still consume items that aren’t guaranteed to be fallout free. These items have to be tested.
Lucky for us we have an Inspector nuclear radiation monitor which I have used for nearly a dozen years in my role as an environmental investigative reporter. While it may not catch everything due to limitations beyond my control, it sure does catch a lot.
When we go shopping, we first aim to shop rad-smart and then test the items upon returning home. Sometimes, however, I will test items in stores to save me the problem of buying something I know could be impacted by Fukushima. Other times, I’ll test the groceries out in the car before driving off.