Indoor Air Pollution

Indoor Air Quality

Indoor Air Pollution

• Indoor air contains higher concentrations of pollutants than outdoor air (up to 70x)

• Indoor air pollution usually is a greater threat to human health than outdoor air pollution.– Avg. U.S. citizen spends 90% of time indoors– 6,000 people die per day from indoor air pollution

related health problems

Most dangerous indoor air pollutants• Cigarette smoke—leads to lung cancer & heart disease• Formaldehyde—colorless, extremely irritating gas used to

manufacture household materials• Building materials (plywood, paneling, high-gloss wood)

– Building Materials (6:43)

• Furniture• Drapes & upholstery• Adhesives in carpeting & wallpaper

• Radioactive Radon-222 gas– Produced by the radioactive decay of uranium-238– Exposes lungs to ionizing radiation– Second leading cause of lung cancer after cigarette smoking– Radon (2:06)– Radon 2 (1:28)

• Asbestos—especially in developing nations– Several different forms of silicate minerals– Widely used as a building material– 1989—EPA ordered a ban on remaining uses of asbestos by 1997– Asbestos (2:16)

• Carbon monoxide—Faulty furnaces, stoves, fireplaces & Cigarette smoking– Causes headache, heartbeat irregularity, & carboxyhemoglobin– Carbon Monoxide (4:44)

• Organic materials—Dust mites, fungal spores, animal dander, hair, carpet fibers– Allergies, coughs, sneezing, eye irritation

• Burning of wood, dung, & coal in open fires—developing nations

Most dangerous indoor air pollutants

Developed Countries

• According to the EPA, the 4 most dangerous indoor air pollutants in developed countries are:– Tobacco smoke– Formaldehyde– Radioactive radon-222 gas– Very small fine & ultrafine particles

Developing Countries

• Solid particulates - from burning wood, charcoal, dung, crop waste– With little to no

ventilation– Soot and carbon

monoxide

Sick-Building Syndrome• A sickness produced by indoor pollution w/

general & nonspecific symptoms• persistent set of symptoms in >20% population• complaints/Symptoms relieved after exiting building• Dizziness, headaches, coughing, sneezing, nausea, & flu-

like symptoms

• New buildings are more commonly “sick” than old ones because of reduced air exchange.– Chemicals released from new carpet, paint and furniture– Can be solved with low-toxicity building materials & good

ventilation

– Sick Building Syndrome (1:05)

Reducing Indoor Air Pollution• In developed countries:

– Use low-toxicity materials– Monitor air quality– Keep rooms clean– Ban indoor smoking– Prevent radon infiltration– Increase intake of outside air– Set stricter formaldehyde emission standards– Limit exposure to chemicals

• In developing countries:– Dry wood before burning– Cook outside– Use less-polluting fuels (natural gas)