Indoor Air Pollution

Indoor vs. Outdoor Air Pollution

• Indoor air pollution is usually much worse than outdoor air pollution– Combustion sources: oil, gas, wood, tobacco– Building materials and furnishings– Household products: cleaning and personal

care– Household appliances: unvented mechanics,

HVAC– Outdoor sources that get indoors: radon, etc.

• Worst in developing countries– Appliances and products without ventilation

Combustion Sources • Sources: unvented space heaters,

leaking chimney or fireplace, back-drafting, gas stoves, attached garage

• Human Health:– Low levels cause flu symptoms, lung

irritation etc.– High levels of CO can kill

Building Materials and Furnishings

• Asbestos– Old or deteriorated insulation or roofing– Carcinogen: lung cancer

• Formaldehyde– Common in particle-board, carpet glues, and

textiles– Eye, nose and throat irritation, allergies,

asthma, possible carcinogen

• Wet or damp areas– Mold and dust, cause irritation and allergy

problems

Household Products• Cleaning products, personal care, pesticides,

and hobby materials (glues, paints, markers)• Toxic materials require proper ventilation!!!• Industrial Solvents are V.O.C.’s

– Benzene (adhesives, dry cleaning, paints, detergent)– Many as solvents: cleaning, hygiene, cosmetics, etc.

• Nausea, fatigue, toxicity, cancer risks

Household Appliances and Systems

• Unvented Appliances– Gas stoves, furnaces, space heaters (CO, NOx,

SO2)

• HVAC Systems– Breed mold and bacteria, and spread it– Legionnaire’s Disease (pneumonia though air

vents)

Outdoor Sources

• Radon– Leaks from soil into

basement and house

• Chimney Effect– Pollutants move

inward through doors and windows and vent upwards through tall, heated buildings

Sick Building Syndrome• Sick Building Syndrome

– Headaches and allergic-like reactions with unspecified stimuli

– Energy efficiency increases indoor pollutants by sealing them inside

– Often related to microbial problems: mold, dust, dust mites, bacteria, and other pathogens

Common Indoor Air Pollutants

• Cigarette smoke*• Formaldehyde*• Radon –222*• Ultra-fine particulates*• Asbestos• Pesticides• Molds• Dust mites and pollens• Legionella pneumophila (and other

bacteria)