The Effects of Exposure Time on Systemic Inflammation in Subjects With Exposure to Zinc- and Copper-Containing Brazing Fumes

Introduction: Inhalation of copper and zinc containing brazing fumes (2.5 mg/m(3) for 6 hours) is able to induce asymptomatic systemic inflammation which is supposed to be connected with an increased risk for cardiovascular disease. In this study it was investigated if inflammation can be prevented by reducing the exposure time. Methods: A total of 15 healthy male subjects were exposed to such brazing fumes in a crossover design for 3, 4, and 5 hours in randomized order. Before and 24 hours after exposure, blood samples were taken and c-reactive protein (CRP) as marker for an acute phase reaction was measured. Results: Five-hour exposure induced an increase of CRP, whereas the shorter exposure times did not result in a significant inflammatory reaction. Conclusions: Reducing daily exposure times below 5 hours is able to prevent systemic inflammatory reactions.