DescriptionCircumstances of exposure and related occupations
Diesel engine exhaust is a complex mixture of both gaseous and particulate components, containing cancer-causing substances including polycyclic aromatic hydrocarbons (PAHs), benzene, 1,3-butadiene, formaldehyde, ethylene oxide, and metals.
The composition and quantity of the emissions from an engine depend mainly on the type and condition of the engine, fuel composition and additives, operating conditions, and emission control devices.


Higher exposures to diesel engine exhaust may occur in some occupations, such as:
  • transportation (e.g. railroad workers and professional drivers) and garage work, vehicle maintenance and examination;
  • traffic control;
  • underground mining;
  • logging;
  • firefighting;
  • dock workers and operation of heavy equipment.