Natural sources, such as volcanoes and forest fires, do not emit significant amounts of air toxics.

Benzene is a known carcinogen that is found in gasoline and other petroleum products.

Inhalation is the primary route of exposure to air toxics, as they are typically present in the air we breathe.

Lead is a known neurotoxin that can cause a variety of neurological problems, including learning disabilities and behavioral problems.

The primary goal of air toxics regulations is to reduce emissions of air toxics, improve air quality, and protect human health.

Carbon monoxide is not an air toxic, as it is not classified as a hazardous air pollutant by the US Environmental Protection Agency (EPA).

Air toxics control is the term used to describe the process of removing air toxics from the air.

Dilution is not a common method of air toxics control, as it does not remove air toxics from the air, but rather disperses them over a larger area.

Acceptable risk level is the term used to describe the level of air toxics in the air that is considered safe for human health.

Age is not a factor that can affect the health effects of air toxics, as people of all ages are equally susceptible to the effects of air toxics.

The EPA is responsible for regulating emissions of air toxics, monitoring air quality for air toxics, and conducting research on the health effects of air toxics.

Carbon monoxide is not a major air toxic emitted by motor vehicles, as it is not classified as a hazardous air pollutant by the EPA.

Risk assessment is the term used to describe the process of assessing the risks posed by air toxics.

Eating a healthy diet is not a common method of reducing exposure to air toxics, as it does not directly affect the levels of air toxics in the air.