Carbon is a Block P, Period 2, nonmetallic element. It is the sixth most abundantly available element in the universe, and is commonly obtained from coal deposits. It is the second most abundant element by mass in the human body after oxygen.
The three naturally occurring allotropes of carbon are graphite, diamond, and amorphous carbon. The morphology of carbon nanoparticles is spherical, and they appear as a black powder. Carbon nanoparticles can be surface functionalized, with organic molecules or polymers chemically bound to the particle surface.
Pure carbon has very low level of toxicity to humans. However, inhalation of coal dust or soot in large quantities can be dangerous, and can cause irritation of lung tissues and a congestive lung disease called pneumoconiosis.