Toner

Toner is a dry, powdered ink used in photocopiers and laser printers. It attaches to paper that has an electrostatic charge and is bonded to the paper by the heat of the fuser.
Toner is not particularly dangerous or toxic, but inhalation can cause symptoms similar to an allergy, and long term exposure (typical of a photocopier repair person) can cause lung disease and even cancer.
Toner at Wikipedia
Category:Toxins