Two year follow up of pulmonary function values among welders in New Zealand.

OBJECTIVES: To examine whether welding is a risk factor for an accelerated decline in pulmonary function. METHODS: 2 Year follow up of pulmonary function and respiratory symptoms among 54 welders and 38 non-welders in eight New Zealand welding sites. RESULTS: There were no significant differences in age, height, smoking habits, ethnicity, or total time in industrial work between welders and non-welders. No overall differences were noted in the changes of pulmonary function variables between the two study groups. However, when the comparison was restricted to smokers, welders had a significantly greater (p = 0.02) annual decline (88.8 ml) in FEV1 than non-welders, who had a slight non-significant annual increase (34.2 ml). Also, welders without respiratory protection or local exhaust ventilation while welding had a greater annual decline both in forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) than welders with protection (p = 0.001 and 0.04, respectively). Among welders a significant association was found between the acute across shift change and the annual decline in FEV1. Chronic bronchitis was more common among welders (24%) than non-welders (5%). Only one welder (2%) but eight non-welders (21%) reported having asthma. CONCLUSIONS: Welders who smoked and welders working without local exhaust ventilation or respiratory protection have an increased risk of accelerated decline in FEV1.