7.5 Indoor Air Pollutants

Common Indoor Air Pollutants

Indoor air pollution can be worse than outdoor pollution because pollutants get trapped in enclosed spaces. Key sources include radon (a radioactive gas from soil/rock that causes lung cancer), carbon monoxide (CO) from incomplete combustion (furnaces, stoves), cigarette smoke, asbestos (insulation fibers linked to lung disease), and formaldehyde from furniture, particleboard, and insulation.

Biological & Combustion Sources

Mold grows in damp areas and releases spores causing allergies/asthma. PM (particulate matter) from cooking, candles, and fireplaces irritates lungs. In developing countries, indoor cookstoves burning wood or biomass release high levels of PM and CO, causing significant respiratory illness and death, especially affecting women and children.

Reducing Indoor Air Pollution

Solutions include improving ventilation, using radon test kits and mitigation systems (sub-slab depressurization), installing CO detectors, banning indoor smoking, removing asbestos safely, and switching to cleaner cookstoves. Sick building syndrome describes illness linked to time spent in poorly ventilated buildings.

Key terms

Radon

A radioactive gas from soil/rock that seeps into homes; a leading cause of lung cancer in nonsmokers.

Carbon monoxide (CO)

A colorless, odorless gas from incomplete combustion that binds to hemoglobin, reducing oxygen transport.

Asbestos

Fibrous mineral once used in insulation; inhaled fibers cause lung diseases like mesothelioma.

Sick building syndrome

Illness symptoms linked to time spent in a poorly ventilated building with trapped indoor pollutants.

Indoor cookstoves

Wood/biomass-burning stoves common in developing countries; major source of PM and CO causing respiratory illness.

Try an AP-style question

Which indoor pollutant is a radioactive gas from uranium in rocks?

1. Carbon monoxide
2. Radon
3. Asbestos
4. Formaldehyde