毒性の高い化合物の粒子発生法とミゼットインピンジャーによるオルトートリジン粒子の捕集効率

抄録

Collection efficiency of midget impinger for o-tolidine particles was determined with a newly developed particle generation system consisting of a glass nebulizer and a glass cylinder. To avoid contamination with toxic substances, 1 cm³ methanol solution of o-tolidine was nebulized and completely dried in the glass cylinder. The total amount of generated particles was controlled by generation time and the size distribution of aerosol particles was adjusted by varying the concentration of nebulised solution. The size distribution of particles was determined with an Andersen sampler followed by a high performance liquid chromatography analysis with ultraviolet or fluorescence detection. The mass median diameters (MMDs) of the generated particles were 0.40, 0.66 and 1.1 μm when the concentrations of nebulized solution were 0.01, 0.1 and 1 g dm^-3, respectively. The geometric standard deviation was 2.0. The collection efficiency of midget impinger did not exceed 30 % when the MMD was 1.1 μm, and it was dependent on the particle size. It is concluded that the evaluation of aiborne particle concentration in working environment by means of the midget impinger is not valid when submicron particles are dominant.