Symptoms associated with building-related health problems are commonly referred to as sick building syndrome. The American Society of Heating, Refrigerating and Air-Conditioning Engineers describes a building in which more than 20 percent of its occupants report building-related illness as a sick building. Symptoms include, but are not limited to, irritation of eyes, nose, and throat; dryness of mucous membranes and skin; erythema; mental fatigue; headaches; airway infections; coughing; hoarseness; wheezing; nausea; dizziness; and unspecific hypersensitivity. It is difficult to identify specific causes of the problem. The complaints reported by the occupants of "sick buildings" are generally nonspecific in nature and, therefore, it is very hard to establish a causal relationship between symptoms and pollutants present in the building.
Even though humans can’t see or smell noise pollution, it still affects the environment. Noise pollution happens when the sound coming from planes, industry or other sources reaches harmful levels. Research has shown direct links between noise and health, including stress-related illnesses, high blood pressure, speech interference and hearing loss. For example, a study by the WHO Noise Environmental Burden on Disease working group found that noise pollution may contribute to hundreds of thousands of deaths per year by increasing the rates of coronary heart disease. Under the Clean Air Act, the EPA can regulate machine and plane noise.
Los Angeles proved to be an ideal location. Flanked by an ocean on one side and by mountains to the north and the east, it is, in terms of air circulation, relatively isolated, Bahreini said. At this location, the scientists made three weekday and three weekend flights with the NOAA P3 research aircraft, which hosted an arsenal of instruments designed to measure different aspects of air pollution. "Each instrument tells a story about one piece of the puzzle," she said. "Where do the particles come from? How are they different from weekday to weekend, and are the sources of vehicle emissions different from weekday to weekend?" she said.