Can all risks be predicted? No, of course not. However, monitoring those that you have identified is critical to investing success. That being said, there are a few that Motley Fool energy and materials analyst Taylor Muckerman covers in the video below. They include margin contraction, supply outstripping demand due to growth projects in place at both PotashCorp (POT) and several of its competitors, and regional disruptions in a few key geographies. While this isn't an exhaustive list, it is at least a starting point for your due diligence process.