Acute Hematologic and Hemorheologic Effects of Sulfur Dioxide Inhalation

Fifty male rats were exposed to 0.87 ppm sulfur dioxide (SO₂) for 24 hr. Hematologic and hemorheologic parameters measured in this group were compared with the results of a control group of 51 male rats. Hematocrit values were found to be higher (p < .005) in the SO₂-treated group (43.55 ± 0.41%, mean ± standard error), when compared to the control group value (41.97 ± 0.35%). Sulfhemoglobin values were also higher (p < .0001) in the SO₂-treated group (0.60 ± 0.08%) than the control group (0.08 ± 0.02%). Osmotic hemolysis ratio was slightly increased (p < .05) in the 0.55% sodium chloride solution. However, whole blood and packed cell viscosities were lower in the SO₂-treated animals, while there was no significant difference in the plasma viscosities. The mechanism of these effects could not be clarified completely, but structural and functional effects of SO₂ inhalation on peripheral erythrocytes were discussed.