We dumped lead all over the environment. You can basically assume anything grown has lead, the only question being how much. Likewise, mercury. In some areas there's a lot of arsenic.
Most everything high on the periodic table is nasty. The few that we willingly associate with are because they are non-reactive enough to not actually pose a threat even if in theory they're harmful. (Consider the use of barium to image the digestive system. They use a form of it that's sufficiently insoluble that you don't get poisoned.)
Most everything high on the periodic table is nasty. The few that we willingly associate with are because they are non-reactive enough to not actually pose a threat even if in theory they're harmful. (Consider the use of barium to image the digestive system. They use a form of it that's sufficiently insoluble that you don't get poisoned.)