RT Journal Article SR Electronic T1 Chronic occupational exposure to nitrogen dioxide is associated with decline in lung function JF Thorax JO Thorax FD BMJ Publishing Group Ltd and British Thoracic Society SP 420 OP 420 DO 10.1136/thx.2004.la0088 VO 59 IS 5 A1 Johns, R YR 2004 UL http://thorax.bmj.com/content/59/5/420.abstract AB