Influence Of Some Domestic Environmental Factors On The Prevalence Of Respiratory Symptoms And Lung Function Changes In Residents Of Three North American Townships

All residents, aged 7 years and above, of three towns were canvassed to participate in a study to determine whether domestic air pollution factors were important in explaining respiratory diseases. Of the 7,203 who participated, this study covers only the 4,074 who were non-smokers. A standardized questionnaire was administered which determined the frequency of cough, phlegm, wheeze, dyspnea, and also domestic factors such as exposure to domestic pets, exposure to gases, vapours and dusts from hobbies, exposure to emissions from gas stoves, the use of fireplaces, air conditioners, humidifiers and heating systems, domestic crowding, and the number of smokers in the home. The forced expiratory volume in one second (FEV(,1)), maximum expiratory flow volume at 25% of vital capacity (MF(,25%)) and maximum expiratory flow volume at 50% of vital capacity (MF(,50%)) were obtained from lung function tests on all subjects.;A small group of symptomatic housewives (26) and matched controls (26) were selected for further study of their actual exposure to sulphur dioxide (SO(,2)), nitrogen dioxide (NO(,2)), and respirable suspended particulates (RSP) within the home. Levels of these pollutants were also determined outside the homes.;Domestic pets and the use of fireplaces and humidifiers had no consistent effects on the reporting of respiratory symptoms nor on lung function when considered individually or in combination with the other exposure factors. Hobbies which exposed residents to gases, vapours and dust, the use of gas stoves, the absence of air conditioning, the use of hot water heating systems, crowded homes, and the presence of smokers in the home all had effects on reporting of symptoms and lung function. The greatest effect on lung function was observed with the use of hot water heating systems, whereas the lowest effect was observed with the number of smokers in the home. There was consistent interaction among the exposure variables by 2-way, 3-way, 4-way and 6-way comparisons. The FEV(,1) of white children showed consistently the greatest responses to all of the exposure variables, so much so, in the 3-way interactions, white boys and girls who lived in homes which had the exposure factors had mean FEV(,1)\u27s of between 0.274 to .397 liters lower than their counterparts who lived in homes which did not have the exposure factors. In a 4-way interaction comparison, white boys and girls who had hobbies which produced gases, vapours and dusts, and lived in homes without air conditioning, but with gas stoves, and with hot water heating systems had mean FEV(,1) of .387 liters and .461 liters respectively lower than their counterparts who had no hobbies and lived in air conditioned homes with forced air heating and with electric stoves. . . . (Author\u27s abstract exceeds stipulated maximum length. Discontinued here with permission of author.) UM