Occupational exposure to hazardous drugs can take place in a number of ways. The main routes of exposures are the dermal absorption, inhalation of aerosolized drugs, injection and ingestion. The workers may be exposed to hazardous drugs by inhalation via droplets, particulates and vapors when they create aerosols, crush the tablets and clean up the spills. Dermal contact can take place when the workers touch the contaminated surfaces during the drug manufacture, administration, handling, storage, disposal and waste treatment. Oral exposure may occur from hand to mouthy contact. Exposures to hazardous drugs through ingestion and injection are although rare but have been acknowledged in recent years.

The drug residues that are present outside the vials can also lead to dermal disinfection and thus contaminates the environment of the healthcare workers even before the actual drug reconstitution begins. According to various researches, contaminations are also found on the surfaces of biological safety cabinets, floors, countertops, safety devices and the areas where patients are treated. By all the research works, it has become clear that occupational exposure to hazardous drugs can take place in several ways and can badly affect the mankind.

Hazardous drugs can also cause various air borne diseases as remarkable amounts of several harmful toxicants in healthcare units air samples have been found. After the drying of the disinfected areas, the drug particulates can become the cause of airborne diseases. Ingestion and injection are also the additional routes of occupational exposures to hazardous drugs. When food products and beverages are prepared, consumed and stored in the work places, they may get disinfected with the airborne particles of these hazardous drugs. A major source of exposure is direct dermal contact that can take place when a leak or spill occurs and a large amount of harmful toxicants are released to the environment. Hence, strict adherence to safety guidelines is mandatory to reduce the risks of exposures.