The body is working with organic molecules more easily. You can literally drink mercury and chew iron and nothing bad will happen (you can, but you shouldn&#x27;t) - you will pass it the next day. We humans cannot absorb non organic molecules easily. A starving person won&#x27;t be able to eat charcoal. The mercury vapors are dangerous because you breathe them in which is easy. Organic compound with mercury can be absorbed trough the digestive tract - and mercury inside the blood stream is big problem.