The did find elevated levels in things like Milk. Even on the east coast. There was also a dramatic rise in birth defects on the west coast.
One of the things that will not show up with radiation detectors are the presence of just a few hot particles in the air. If you breath in one then it gets stuck in you, and exposes you for the long run. It was claimed that these had been found in various air filters here in the US.
Agreed.