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Toxins in Everyday Life - Indoor Air Toxins

pollution building exposures million

Indoor pollution has become a serious problem in America. Although most people think of outdoor air when they think of air pollution, studies now reveal that indoor environments are not safe havens from air pollution. As discussed earlier, lead, asbestos, radon, and ETS all pose serious and costly problems in indoor settings. Modern indoor environments contain a variety of pollution sources, including synthetic building materials, consumer products, and dust mites (minute insects that live on house dust and human skin residue). People, pets, and indoor plants also contribute to airborne pollution. Improvements in home and building insulation and the widespread use of central air conditioning and heating systems have largely ensured that any contaminant present indoors will not be diluted by outside air and, therefore, will become more concentrated.

Indoor pollution, however, is not just a product of modern, well-insulated homes and buildings. In 1995 doctors in the Bronx, New York, began observing an emerging epidemic of asthma, citing hospitalization rates as high as 17.3 per 1,000 people and death rates as high as 11 per 100,000. Both rates were eight times the national average and the rate of incidence among children was twice the national rate. The Bronx, an area with many dilapidated and neglected buildings, is among the worst places in the country for asthma. Among the causes cited by area physicians were many factors associated with indoor pollution: dust mites, cockroaches, smoking, dust, and respiratory viruses and bacteria (which spread easily in crowded quarters). Scientists suspected that stress and the start-up of a waste incinerator in the Bronx three years earlier were factors as well.

The EPA and other sources identify indoor pollution as one of the most serious environmental risks to human health because:

  • concentrations of pollutants in indoor air can be more than two to five times higher than those in outdoor air;
  • people spend an average of 80 to 90 percent of their time indoors, even more for certain groups, such as the elderly, the chronically ill, and the very young; and
  • the indoor environment is unique in that it contains materials and surfaces that act as emitters and reservoirs of pollutants.

Reports of illness and allergy among building occupants have become commonplace. Scientific evidence suggests that respiratory diseases, allergies, mucous membrane irritation, nervous system defects, cardiovascular symptoms, reproductive problems, and lung cancer may be linked to exposure to indoor air pollution.

Poorly ventilated buildings sometimes become the cause of "sick-building syndrome." The term, first employed in the 1970s, describes a spectrum of specific and nonspecific complaints reported by building occupants. Such symptoms might include headaches, fatigue, or difficulty breathing, which begin soon after entering a building and subside after leaving that building. When 20 percent of a building's occupants report complaints, the World Health Organization (WHO) calls that building "sick." Experts generally believe there are many people who do not complain, even when they experience symptoms, and the WHO and the EPA estimate that 30 percent of all buildings worldwide are unfit for human occupation. Surveys and assessments by private corporations and federal agencies estimate that sick-building syndrome goes undetected in another 10 to 15 percent of structures. Many billions of dollars in income and productivity are lost annually because of employees falling ill from problems linked to sick-building syndrome.

The first legislation to deal specifically with indoor air quality was Title IV of the Superfund Amendments and Reauthorization Act of 1986, which called for the EPA to establish an advisory committee to conduct research and disseminate information. In October 1991 the GAO reported on the progress of the legislation in Indoor Air Pollution: Federal Efforts Are Not Effectively Addressing a Growing Problem. The GAO concluded not only that the EPA's emphasis on indoor pollution was not commensurate with the health risks posed by the problem, but also that research had been, and would likely continue to be, constrained by a lack of funding. Accordingly, the proposed Indoor Air Quality Act of 1991 was not enacted by Congress.

Federal agencies reported that they spent a total of almost $1.1 billion on indoor pollution-related research from 1987 to 1999. Most of that amount went toward indoor air research, followed by studies of lead, asbestos, and radon. The NIEHS spent the most (almost $400 million), with the National Heart, Lung, and Blood Institute spending $175.2 million, the EPA $140.4 million, the DOE $136.5 million, and the National Institute of Allergy and Infectious Diseases $93.7 million.

In 1999 the GAO once again reviewed the status of indoor air quality activities. In Indoor Pollution: Status of Federal Research Activities, the GAO found that significant strides have been made in understanding the risks posed by chemicals and other contaminants commonly found in homes, offices, and schools. Nonetheless it concluded that "many gaps and uncertainties remain in the assessment of exposures to known indoor pollutants." These gaps include specific sources of exposures; the magnitude of exposures; the relative role of specific exposures such as inhalation, ingestion, and skin contact; the nature, duration, and frequency of human activities that contribute to exposures; and the geographic distribution of exposures to certain pollutants for the U.S. population as a whole.

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over 8 years ago

hi i am a fifth grade student at tops school and i was wondering if you have heard of green chemicals if you have have you used them to rid of dangerous chemicals. if you can that would be great thank you