140622-1413 EDT
Quite possibly.
With the neutral open at the weatherhead this means all neutral current will flow thru whatever paths there are to one or more ground rods at power company transformers and/ or thru neighbors grounding and neutral paths, and water lines. There can be much higher impedances thru these paths than thru the open neutral, if it were not open. The basement floor is not necessarily at the same potential as these other various paths.
With bare feet on a wet floor 1 V might be dangerous.
In my home there might not be much difference because the 1.25" copper water line runs diagonally under the basement floor and thus has good coupling to the floor, and is also the grounding electrode. My single neighbor on the transformer has a water supply common to me, but possibly thru a mile of city water line. Our transformer is connected to a single ground rod, and to no other transformers on the secondary side.
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