Human experiments were performed on six volunteers, who had never experienced CS2 absorption, with different concentrations of carbon disulfide (CS2) from 28 ppm to 52 ppm which were inhaled for 30 to 120 minutes continuously, and CS2 concentration was kept at a constant level during the period of each experiment. Amounts of CS2 retained in the body and eliminated from it by the expired air, the skin, and the urine were calculated. During the period of each inhalation experiment, the volunteers were free from any signs, except a slight headache. The results are summarized as follows:
The percentage of CS2 concentration in the expired air to that in the inspired rises gradually for the first 40 minutes and reaches an equilibrium at 65 ± 10 per cent.
When the inhalation of CS2 is discontinued, CS2 level in the expired air rapidly goes down in fresh air, and the average percentage of CS2 concentration in the expired air to that in the air which has been inhaled is 18 ± 5, 8 ± 2 and 4 ± 2 per cent at the interval of every 10 minutes. The decrease presents the geometrical series.
The amount of CS2 absorbed during the inhalation is calculated to be from 15.4 mg to 29.6 mg (average 23.0 mg), of which 1.74 mg to 7.58 mg (average 4.82 mg) is eliminated by the expired air, while the amount of CS2 excreted in the urine is from 7.2 γ to 37.3 γ (average 16.5 γ).
CS2 is proved to be eliminated through the skin in the amount of 36.2 γ to 77.8 γ. This is about three times as much as that eliminated by the urine, and it is about 1% of the amount eliminated by the respiratory tract.
The balance sheet of CS2 in the body is prepared and described, taking into account the absorption, on the one hand, and the elimination, on the other, of gaseous CS2 through the respiratory tract, the skin, and the urine.