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The magnitudes of the hand-transmitted vibration, 297 hand-held tools and workpieces were measured at workplaces. The tools were used mainly in construction and manufacturing industries. The current standard for the measurement of hand-transmitted vibration has been based on the frequency-weighted acceleration of dominant axis method. According to the proposal of ISO/CD5349-1, the results of measurements (462 points) were recalculated by the method of the frequency-weighted acceleration sum. There is 32% of difference in average value between the acceleration sum and the dominant axis method.

Rabbits were exposed to mercury vapor at concentrations from 0.03 to 10 mg Hg m−3 for 3 and 8 h. Mercury concentrations in urine, red blood cells and plasma, activities of several enzymes in urine, urinary protein and creatinine concentrations, and catalase activities in red blood cells were determined before and during the exposure. During latent periods for the detection of mercury after the start of exposure in urine, red blood cells or plasma showed an inverse correlation with the level of mercury in the inspired air. When the air mercury level was 1.5 mg Hg m−3 or below, mercury was not detected in plasma, in spite of a clear rise of urinary and erythrocytic mercury levels in the early time period during exposure. However, with air mercury higher than 2 mg Hg m−3, mercury was detected in urine, red blood cells and plasma. Urinary protein, urinary enzyme activities and blood catalase were unaffected during the course of exposure.

Mercury in cigarettes of domestic and foreign products was measured by Magon's method, and the sample of a domestic brand was burned by a smoking machine and the smoke was collected for the measurement of mercury. In tobacco leaf and paper, only inorganic mercury was found in both domestic and foreign products. Its amount in tobacco leaf and paper of a piece of cigarette was about 60 ng in domestic products and about 30 ng in foreign products. By burning, the unit length of a cigarette released about 5-7 ng of mercury into smoke.

Fourteen Japanese females exposed to elemantal mercury vapour of concentration; 0.001–0.019 mg Hg/m3, were examined for inorganic and organic mercury concentrations in red blood cells, plasma, urine, and hair. Examinations were conducted the times; at 0,4 and 8 months of mercury exposure. No significant change of inorganic and organic mercury in urine was observed for three examinations. Both inorganic and organic mercury in plasma, and only organic mercury in red blood cells, increased significantly after commencement of mercury work. The hair organic mercury values stayed constant. The intake of organic mercury was judged as constant from the constancy of hair mercury values, and the change of organic mercury concentrations in plasma and red blood cells must have been elicited from the intake of elemental mercury. The reason why the increase of plasma mercury values did not reflect to urine mercury values was discussed.