Health risk evaluation of nitrogen oxides
Berglund, M; Bostrom, CE; Bylin, G; Ewetz, L; Gustafsson, L; Moldeus, P; Norberg, S; Pershagen, G; Victorin, K
HERO ID
33986
Reference Type
Journal Article
Year
1993
Language
English
PMID
| HERO ID | 33986 |
|---|---|
| In Press | No |
| Year | 1993 |
| Title | Health risk evaluation of nitrogen oxides |
| Authors | Berglund, M; Bostrom, CE; Bylin, G; Ewetz, L; Gustafsson, L; Moldeus, P; Norberg, S; Pershagen, G; Victorin, K |
| Journal | Scandinavian Journal of Work, Environment and Health |
| Volume | 19 |
| Page Numbers | 2) |
| Abstract | The nitrogen oxides discussed in this document are nitric oxide (NO) and nitrogen dioxide (NO2). In combustion processes, NO is primarily formed and subsequently oxidized to NO2 in the atmosphere. Traffic is the major source to human outdoor exposure to NO and NO2 in urban areas. In homes with gas-fueled stoves or water heaters, the concentration of NO2 is generally higher indoors than outdoors. Upon inhalation, NO2 penetrates deep into the lung. In animal experiments, NO2 causes biochemical and morphological changes in lung tissue, affects host defense mechanisms, and causes decreased pulmonary function. The lowest observed effect level after prolonged exposure is 560 mug.m-3. In short-term controlled studies on humans, NO2 causes bronchoconstriction and an increase in bronchial responsiveness. A meta-analysis indicates a lowest observed effect level of 200 mug.m-3 for increased bronchial responsiveness in asthmatics. Epidemiologic studies on children living in homes with gas stoves suggest an increased risk of lower respiratory illness at average indoor NO2 concentrations of about 40-80 mug.m-3, with short-term peaks exceeding 1000 mug.m-3. The studies focusing on outdoor exposure provide some evidence of increased respiratory disease rates for children and nonsmoking adults living in areas with long-term average NO2 concentrations of 30-100 mug.m-3; however, the specific role of NO2 is not clear. Based on controlled studies on humans, a 1-h guideline value of 100 mug.m-3 for NO2 in ambient air (eg, as the 99th percentile) is recommended. This value would correspond to a long-term average (half-year mean) of about 40 mug.m-1. The epidemiologic evidence is not considered sufficient for a long-term guideline for NO2. NO is formed endogenously for purposes such as signaling in the nervous system, the mediation of vasodilation, and the mediation of cytotoxicity in macrophages. After the inhalation of high concentrations of NO, lung vasodilator effects occur. No health-based guideline value for NO in ambient air is suggested. |
| Pmid | 8209191 |
| Wosid | WOS:A1993NB32400001 |
| Is Certified Translation | No |
| Dupe Override | No |
| Comments | ECRIB.Scand. J. Work Environ. Health 19(suppl 2). |
| Is Public | Yes |
| Language Text | English |
| Is Qa | No |