The green tinted posts that hold up grape vines have become a part of the landscape over the last couple of decades. They're treated with a solution of poisonous chemicals including arsenic that some studies have shown, can leach out. The crisis in the wine industry has seen scores of vineyards mothballed and the posts either left in the ground or pulled out and stacked in piles. Prue Adams reports there are growing concerns about their use and disposal.
