Do ya think it's perhaps something on these shells he bought at hobby lobby Jay? Seems big coincidence that everything went south right after they were dropped in? Hopefully OP has removed them regardless....Remember though - ICP will only show elemental levels, copper, iron, sodium, etc. If the toxin were an organic compound (likely) the ICP process would only show it in its elemental forms, and you'd never even notice it. Even ammonia and nitrate won't show in ICP.
Jay