Pollution

Secondhand Smoke

Secondhand smoke is classified as a "known human carcinogen" (cancer-causing agent) by the US Environmental Protection Agency (EPA), the US National Toxicology Program, and the International Agency for Research on Cancer (IARC), a branch of the World Health Organization.

Benzene

Benzene is a colorless, flammable liquid with a sweet odor. The link between benzene and cancer has largely focused on leukemia and cancers of other blood cells.

Radon

Radon is a colorless, odorless, radioactive gas. Long-term exposure to radon can lead to lung cancer.

Diesel Exhaust

Diesel is a type of fuel derived from crude oil. Large engines, including those used in many trucks, buses, trains, construction and farm equipment, generators, ships, and in some cars, run on diesel fuel.

MTBE

MTBE (methyl tertiary-butyl ether) other oxygenates make gasoline burn better. Despite its potential benefits to air quality, MTBE has some properties that can cause problems.