Recently the Japanese Industrial Standard on HEPA Filters for radioactive aerosols (JIS Z 4812) was revised, in which the standard particle size was changed to 0.15μm from 0.3μm. A new 0.15μm DOP aerosol generator was developed for in-place filter testing. The aerosol generator is of the vaporization-condensation type. The generated DOP aerosol were found to be quasi-monodispersive with a geometric standard deviation (σg) of less than 1.2 by laser aerosol spectrometer measurements. A typical size distribution of test aerosol was a count median diameter (CMD)=0.151μm and σg=1.15. The number concentration was 1.4×104/cm3 at an air flow rate of 7, 800m3/h. The stability, portability and operability of the new generator were also evaluated.
This study was conducted to investigate the effect of diethylenetriaminepentaacetic acid (DTPA) on the concentrations of some metal elements in mouse organs to accumulate fundamental knowledge on its pharmacological properties and its side effects. DTPA was injected intraperitoneally into C3H/He mice 3 times per week at a dose of 0.3mmol per kg body weight, and the concentrations of 13 metal elements in the liver, spleen kidneys, lungs, femur and serum were measured by inductively coupled plasma emission spectrometry and atomic absorption spectrometry up to 8 weeks after the start of administration. The concentrations of Co, Cr, Ni, Ti and V were at undetectable levels in the control and treated groups throughout the experimental period in all the organs examined. The concentrations of Ca slightly changed with the DTPA treatment in the liver and femur. The concentrations of Mn in the liver and P in the femur also slightly changed with the DTPA treatment, but no general tendency was apparent. The concentrations of Cu and Al significantly increased with the DTPA treatment in the liver and kidneys and Zn also increased in the kidneys. The concentrations of Mg significantly decreased with the DTPA treatment in all the organs except the lungs. The Fe concentrations tended to decrease in the liver and spleen, although the decrease was slight. In conclusion, the concentrations of several metal elements were changed by the administration of Ca-DTPA, but the change was small.