6Cyrys J, Heinrich J, Richter K,et al. Sources and concentrations of indoor nitrogen dioxide in Hamburg(West Germany) and Erfurt(East Germany)[J]. The Science of the Total Environment,2000,250(1-3):51-62.
7Yan PB, Hemphill CP, Billick IH,et al.Estimation of nitrogen dioxide concentrations in homes equipped with unvented gas space heaters[J].Environment International,1989,15 (1): 551-556.
8Viegi G, Carrozzi L, Paoletti P,et al.Effects of the home environment on respiratory symptoms of a general population sample in middle Italy[J]. Archives of Environmental Health, 1992, 47 (1):64-70.
9Pilotto L S, Douglas R M, Attewell R G,et al. Respiratory effects associated with indoor nitrogen dioxide exposure in children[J]. International Journal of Epidemiology, 1997, 26 (4):788-796.
10L(e)vesque B, Gauvin D, McGregor R,et al.Radon in residences: influences of geological and housing characteristics[J].Health Physics, 1997, 72 (6):907-914.
5Dockery D W, Pope C A. Acute respiratory effects of partic- ulate air pollution[J]. Annu Rev Public Health, 1994, 15: 107 - 132.
6Bascom R, Bromberg P A, Costa D A, et al. Health effects of outdoor air pollution [ J ]. Part 1 Am J Respir Crit Care Med. 1996, 153:3 -50.
7Parekh P P, Khwaja H A, Khan A R, et al. Ambient air quality of two metropolitan cities of Pakistan and its health implications [ J ]. Atmospheric Environment, 2001, 35 : 5971 - 5978.
8Peel J L, Tolbert P E, Klein M, et al. Ambient air pollution and respiratory emer - gency department visits [ J ]. Epide- niology, 2005, 16(2) : 164 - 174.
9Gurjar B R, Manju M, Sidhu K S. Potential health risks re- ated to carcinogens in the atmospheric environment in India iJ]. Regut Toxicol Pharm, 1996, 24(2) : 141 - 148.