What are toxic air pollutants?
Toxic air pollutants, also known as hazardous air pollutants, are those pollutants that are known or suspected to cause
cancer or other serious health effects, such as reproductive effects or birth defects, or adverse environmental effects.
EPA is working with state, local, and tribal governments to reduce air toxics releases of
188 pollutants to the
environment. Examples of toxic air pollutants include benzene, which is found in gasoline; perchlorethlyene, which is
emitted from some dry cleaning facilities; and methylene chloride, which is used as a solvent and paint stripper by a
number of industries. Examples of other listed air toxics include dioxin, asbestos, toluene, and metals such as cadmium,
mercury, chromium, and lead compounds.
0 Antimony Compounds  
0 Arsenic Compounds (inorganic including arsine)  
0 Beryllium Compounds  
0 Cadmium Compounds  
0 Chromium Compounds  
0  Cobalt Compounds  
0 Cyanide Compounds1  
0 Lead Compounds
0 Manganese Compounds  
0 Mercury Compounds  
0 Nickel Compounds  
0 Selenium Compounds

What are the health and environmental effects of toxic air pollutants?
People exposed to toxic air pollutants at sufficient concentrations and durations may have an increased chance of
getting cancer or experiencing other serious health effects. These health effects can include damage to the immune
system, as well as neurological, reproductive (e.g., reduced fertility), developmental, respiratory and other health
problems. In addition to exposure from breathing air toxics, some toxic air pollutants such as mercury can deposit onto
soils or surface waters, where they are taken up by plants and ingested by animals and are eventually magnified up
through the food chain. Like humans, animals may experience health problems if exposed to sufficient quantities of air
toxics over time.

How are people exposed to air toxics?
People are exposed to toxic air pollutants in many ways that can pose health risks, such as by:

Breathing contaminated air.
Eating contaminated food products, such as fish from contaminated waters; meat, milk, or eggs from animals that fed on
contaminated plants; and fruits and vegetables grown in contaminated soil on which air toxics have been deposited.
Drinking water contaminated by toxic air pollutants.
Ingesting contaminated soil. Young children are especially vulnerable because they often ingest soil from their hands or
from objects they place in their mouths.
Touching (making skin contact with) contaminated soil, dust, or water (for example, during recreational use of
contaminated water bodies).
Once toxic air pollutants enter the body, some persistent toxic air pollutants accumulate in body tissues. Predators
typically accumulate even greater pollutant concentrations than their contaminated prey. As a result, people and other
animals at the top of the food chain who eat contaminated fish or meat are exposed to concentrations that are much
higher than the concentrations in the water, air, or soil.

National Primary Drinking Water Regulations

Drinking water  Contaminant and health effects
Metals --
Organic Chemical

40 CFR 423A: Appendix A to Part 423 -- 126 Priority Pollutants 40 CFR 423, App A CFR