title: Effects of nitrogen oxides on natural killer cells in glass craftsmen and braziers.
abstract: OBJECTIVE
  To assess the effect of exposure to nitrogen oxides on peripheral blood natural killer cells.
  
  
  METHODS
  Groups of glass craftsmen and braziers exposed to nitrogen oxides and non-exposed controls were studied. Air concentrations of nitrogen oxides were measured. Mononuclear cells isolated from peripheral blood samples were assayed for natural killer cell activity with K562 target cells in a 51Cr release assay and the percentage of natural killer cells (CD16) was measured by flow cytometry.
  
  
  RESULTS
  Braziers were exposed to 1.2 ppm nitrogen dioxide and 8.6 ppm nitric oxide and glass craftsmen to 2.9 ppm nitrogen dioxide and 26.5 ppm nitric oxide. The natural killer cell activity of exposed workers was significantly lower than in non-exposed controls (P < 0.05 ANOVA Scheffe test). The percentage of natural killer cells in glass craftsmen was significantly greater than in controls (P < 0.05 ANOVA Scheffe test). Regression of natural killer cell activity against age, smoking habit, number of years worked and current exposure to nitrogen dioxide and nitric oxide gases was not significant. The percentage of natural killer cells was not significantly correlated with age, smoking habit, or numbers of years worked, but was significantly related to air concentrations of nitrogen dioxide (P < 0.01) and nitric oxide (P < 0.001).
  
  
  CONCLUSIONS
  Natural killer cell activity and the percentage of natural killer cells in peripheral blood cells were altered in workers exposed to nitrogen oxides.
authors.affiliation: Department of Environmental and Occupational Medicine, Newcastle University, Newcastle Upon Tyne.
authors.forename: M R
authors.initials: MR
authors.lastname: Azari
authors.forename: F M
authors.initials: FM
authors.lastname: Williams
authors.forename: J
authors.initials: J
authors.lastname: Kirby
authors.forename: P
authors.initials: P
authors.lastname: Kelly
authors.forename: J W
authors.initials: JW
authors.lastname: Edwards
authors.forename: P G
authors.initials: PG
authors.lastname: Blain
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D016022:Case-Control Studies; D002860:Chromium Radioisotopes; D005898:Glass; D006801:Humans; D007694:Killer Cells, Natural / Q000187:drug effects*; D008669:Metallurgy; D008875:Middle Aged; D009589:Nitrogen Oxides / Q000009:adverse effects* / Q000097:blood*; D016273:Occupational Exposure / Q000009:adverse effects* / Q000032:analysis
chemical_list: D002860:Chromium Radioisotopes; D009589:Nitrogen Oxides