Generation of Li combustion aerosols for animal inhalation studies

A system was developed for generating Li aerosols to determine the potential health hazards of postulated accidents associated with the use of Li as a fusion reactor blanket or coolant. The aerosol was generated by sweeping Ar through a stainless steel chamber filled with Li metal that was heated inductively to temperatures up to 1300 degrees C. Argon carried the Li vapor into a burning chamber where it was mixed with air. The reaction of Li vapor with air formed an intense white flame that produced typical branched-chain condensation aerosol particles. This system generated well-controlled concentrations up to 2500 mg/m3 for periods of 4 h. The mass median aeordynamic diameter of the aerosol was approximately 0.66 micron with a geometric standard deviation of 1.5. Aerosols could be generated that were greater than 96% Li2O and LiOH, LiOH.H2O, or Li2CO3 by controlling the CO2 and H2O concentrations in the supply air. The system is currently being used to investigate the acute toxicity of Li combustion aerosols in laboratory animals.