Formaldehyde is an important chemical used widely by industry to manufacture buildingmaterials and numerous household products. It is also a by-product of combustion and certain other natural processes. Thus, it may be present in substantial concentrations both indoors and outdoors.
Sources of formaldehyde in the home include building materials, smoking, household products, and the use of unvented, fuel-burning appliances, like gas stoves or kerosene space heaters.
Exposure to formaldehyde vapors can cause eye, nose and throat irritation; coughing; skin rashes; headaches; dizziness; nausea; vomiting and nosebleeds. Formaldehyde has also been shown to cause cancer in laboratory animals, and the U.S. Environmental Protection Agency (EPA) ranks formaldehyde as a probable human carcinogen. However, the most recent EPA estimate of the lifetime cancer risk associated with exposure to formaldehyde in homes is equal or less than 1 chance in a million of developing cancer.
Carbon Monoxide (CO)
Sources of Carbon Monoxide can be found in unvented kerosene and gas space heaters; leaking chimneys and furnaces; back-drafting from furnaces, gas water heaters, wood stoves, and fireplaces; gas stoves; generators and other gasoline powered equipment; automobile exhaust from attached garages; and tobacco smoke.
At low concentrations, exposure to carbon monoxide can show fatigue in healthy people and chest pain in people with heart disease. At higher concentrations, impaired vision and coordination; headaches; dizziness; confusion; nausea may occur. Carbon Monoxide may also cause flu-like symptoms that clear up after leaving home. Exposure at very high concentrations can be fatal.
Volatile Organic Compound (VOC)
EPA’s Total Exposure Assessment Methodology (TEAM) studies found levels of about a dozen common organic pollutants to be 2 to 5 times higher inside homes than outside, regardless of whether the homes were located in rural or highly industrial areas. Additional TEAM studies indicate that while people are using products containing organic chemicals, they can expose themselves and others to very high pollutant levels, and elevated concentrations can persist in the air long after the activity is completed.
Sources of VOC can be found in household products including: paints, paint strippers, and other solvents; wood preservatives; aerosol sprays; cleansers and disinfectants; moth repellents and air fresheners; stored fuels and automotive products; hobby supplies; dry-cleaned clothing.
Health Effects can range from eye, nose, and throat irritation; headaches, loss of coordination, nausea; damage to liver, kidney, and central nervous system. Some organics can cause cancer in animals; some are suspected or known to cause cancer in humans.
The ability of organic chemicals to cause health effects varies greatly from those that are highly toxic, to those with no known health effect. As with other pollutants, the extent and nature of the health effect will depend on many factors including level of exposure and length of time exposed. Eye and respiratory tract irritation, headaches, dizziness, visual disorders, and memory impairment are among the immediate symptoms that some people have experienced soon after exposure to some organics. At present, not much is known about what health effects occur from the levels of organics usually found in homes. Many organic compounds are known to cause cancer in animals; some are suspected of causing, or are known to cause, cancer in humans.
Nitrogen Dioxide (NO2)
Sources of Nitrogen Dioxide can be found in kerosene heaters, un-vented gas stoves and heaters, and environmental tobacco smoke.
Health Effects Associated with Nitrogen Dioxide can cause eye, nose, and throat irritation. It may cause impaired lung function and increased respiratory infections in young children.
Molds are usually not a problem indoors, unless mold spores land on a wet or damp spot and begin growing. Molds have the potential to cause health problems. Molds produce allergens (substances that can cause allergic reactions), irritants, and in some cases, potentially toxic substances (mycotoxins). Inhaling or touching mold or mold spores may cause allergic reactions in sensitive individuals. Allergic responses include hay fever-type symptoms, such as sneezing, runny nose, red eyes, and skin rash (dermatitis). Allergic reactions to mold are common. They can be immediate or delayed. Molds can also cause asthma attacks in people with asthma who are allergic to mold. In addition, mold exposure can irritate the eyes, skin, nose, throat, and lungs of both mold-allergic and non-allergic people. Symptoms other than the allergic and irritant types are not commonly reported as a result of inhaling mold.