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Air Toxics

Air toxics (toxic air pollutants) are hazardous gases or dusts in the atmosphere suspected of causing serious health effects, including those related to breathing problems. Examples include: (1) benzene, a minor component of gasoline, but of concern since it continually escapes through evaporation or spillage; (2) perchlorethlyene, which escapes from dry cleaning operations; (3) methylene chloride, a paint stripper; (4) dioxin, from diesel exhaust and power plants emissions; (5) polycyclic aromatic hydrocarbons (PAHs) and polycyclic chlorinated biphenyls (PCBs), also products from combustion; (6) asbestos, from building demolition, (7) metallic compounds, especially from cadmium, mercury, chromium, and lead.

Clearly, most air toxics are seen to originate from various man-made sources – cars, trucks, and buses, as well as from factories, refineries, and power plants. Indoor sources, such as solvents and building materials also contribute. Natural sources (forest fires and volcanic eruptions) can add a very major contribution, whenever they occur.

People exposed to air toxics at elevated concentrations and/or for extended periods have an increased risk of disease or damage to their immune systems, as well as to their neurological, reproductive, developmental or respiratory systems.

Air toxics exposure routes include: (1) breathing contaminated air; (2) eating contaminated food, including fish from contaminated waters; (3) eating meat, milk, or eggs from animals that eat contaminated plants; (4) eating fruits and vegetables grown in soil contaminated by air toxics deposited by rainfall; (5) drinking water contaminated by toxic air pollutants, and (6) by taking in contaminated soil: young children can ingest traces of soil from hand-to-mouth behavior.

HEASD scientists have published a number of articles and reports on air toxics. Links to a selection of these articles and reports will be available here.

Human Exposure and Atmospheric Sciences

Research & Development | National Exposure Research Laboratory


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