Pulmonary effects of sulfur oxides on the surface of copper oxide aerosol.

The authors have developed a system that generates copper oxide aerosol similar to the primary emissions from smelters. The surface of the ultrafine copper oxide aerosol is coated with a layer of sulfur oxides consisting of sulfate, S(VI), and sulfite, S(IV). Guinea pigs were exposed to this sulfur oxide layered copper oxide aerosol, and pulmonary mechanical functions were measured by using the Amdur-Mead method. The concentration of sulfur oxides on the aerosol was determined by using a flame photometric detector system. Although sulfuric acid was not found in this system, S(IV) at concentrations as low as 0.36 mumol/m3 delivered as a surface layer caused prolonged changes in pulmonary mechanical functions.