Occupational exposure is defined as any contact between the human body and a potentially harmful agent or environment in the workplace. Exposures to many carcinogens (e.g. asbestos, cadmium, and benzene) occur in occupational settings.

Chemical hazards for workers working in industries dealing with various chemical like petroleum, arsenic, asbestos, aluminum, rubber production, radian, leather, coal tar, iron, wood, paint etc. are important causes of occupational hazards.