I don't know the answer to your question.  I did Google "bromodiolone" and found this fact sheet on Bromodiolone.  I thought it was interesting. 

My comment would be: whether it is good or not, I would think the best way to dispose of this would still be to use it in an intended manner.  OR have it disposed of professionally. 

If you don't get an answer to your question any other way, maybe call the National Pesticide Hotline, listed at the top of the Fact sheet.